56 results on '"Hu, Yuan"'
Search Results
2. Non‐Flammable Electrolyte with Lithium Nitrate as the Only Lithium Salt for Boosting Ultra‐Stable Cycling and Fire‐Safety Lithium Metal Batteries.
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Liao, Can, Han, Longfei, Wang, Wei, Li, Wanqing, Mu, Xiaowei, Kan, Yongchun, Zhu, Jixin, Gui, Zhou, He, Xiangming, Song, Lei, and Hu, Yuan
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LITHIUM cells ,ELECTROLYTES ,SOLID electrolytes ,FLAMMABLE limits ,LITHIUM - Abstract
Lithium metal batteries (LMBs) attract considerable attention for their incomparable energy density. However, safety issues caused by uncontrollable lithium dendrites and highly flammable electrolyte limit large‐scale LMBs applications. Herein, a low‐cost, thermally stable, and low environmentally‐sensitive lithium nitrate (LiNO3) is proposed as the only lithium salt to incorporate with nonflammable triethyl phosphate and fluoroethylene carbonate (FEC) co‐solvent as the electrolyte anticipated to enhance the performance of LMBs. Benefiting from the presence of NO3− and FEC with strong solvation effect and easily reduced ability, a Li3N–LiF‐rich stable solid electrolyte interphase is constructed. Compared to commercial electrolytes, the proposed electrolyte has a high Coulombic efficiency of 98.31% in Li‐Cu test at 1 mA cm−2 of 1.0 mAh cm−2 with dendrite‐free morphology. Additionally, the electrolyte system shows high voltage stability and cathode electrolyte interphase film‐forming properties with stable cycling performances, which exhibit outstanding capacity retention rates of 96.39% and 83.74% after 1000 cycles for LFP//Li and NCM811//Li, respectively. Importantly, the non‐flammable electrolyte delays the onset of combustion in lithium metal soft pack batteries by 255 s and reduces the peak heat release by 21.02% under the continuous external high‐temperature heating condition. The novel electrolyte can contribute immensely to developing high‐electrochemical‐performance and high‐safety LMBs. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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3. Ultrathin and Mechanically Robust Mussel Byssus‐Inspired MXene@Aramid Nanofibers Materials with Superior Endurance in Harsh Environments for Tunable EMI Shielding Performance.
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Lu, Jingyi, Cheng, Liang, Liao, Can, Jia, Pengfei, Song, Lei, Wang, Bibo, and Hu, Yuan
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MUSSELS ,FIRE prevention ,NANOFIBERS ,MOTHER-of-pearl ,ELECTROMAGNETIC interference ,VISION - Abstract
Reducing the fire hazards caused by high power electromagnetic (EM) waves and maintaining operational status of EM interference (EMI) shielding devices in harsh environments have caught increasing eyesight. In this paper, a series of promising EMI shielding materials with mussel byssus‐inspired structure are accomplished via an efficient vacuum‐assisted filtration approach. The flexible multilayered MXene@ANF nacres reveal superior mechanical property compared with both self‐supporting MXene film and MXene@ANF mixture film. Meanwhile, these nacres exhibit both exceeding and tunable EMI shielding effectiveness (EMI SE) of 40–60 dB in 8.2–12.4 GHz with a thickness of ≈20 µm and the absolute SE (SSEt) accomplishes 36641.94 dB·cm2 g−1. Besides, the exceeding thermal insulation of ANF offers the MXene nacres with an outstanding flame‐stopping capacity, and it can still block 99.99% EM waves after 2 min burning. Furthermore, MXene nacres perform superior endurance in harsh environment and retain EMI SE of 42 dB after the ultralow temperature damage. The EMI SE and fire safety of MXene@ANF with two typical structures, composite films and foam, are also systematically investigated. Therefore, this work is promising to fabricate tunable EMI shielding products with low fire hazards and high endurance in harsh environments. [ABSTRACT FROM AUTHOR]
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- 2022
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4. Recent Progress in Two-dimensional Nanomaterials Following Graphene for Improving Fire Safety of Polymer (Nano)composites.
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Cai, Wei, Wang, Bi-Bo, Wang, Xin, Zhu, Yu-Lu, Li, Zhao-Xin, Xu, Zhou-Mei, Song, Lei, Hu, Wei-Zhao, and Hu, Yuan
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MOLYBDENUM disulfide ,FIRE resistant polymers ,FIRE prevention ,NANOSTRUCTURED materials ,METAL-organic frameworks ,FIREPROOFING agents ,POLYMERS - Abstract
The high fire safety of polymer nanocomposites is being pursued by research institutions around the world. In addition to intrinsic flame retardancy strategy, the additive-type flame retardants have attracted increasing attention due to low commercial cost and easy fabrication craft. However, traditional additive-type flame retardants usually need high addition amount to achieve a desirable effect, which causes many side-effects on the overall performance of polymer materials, such as deteriorated mechanical property and processability. At present, two-dimensional (2D) nanomaterials have also been applied to reduce the fire hazards of polymer (nano)composites with the coupling of barrier function and catalysis as well as carbonization effect. Even though most research work mainly focus on graphene-based flame retardants, more emerging two-dimensional nanomaterials are taking away research attention, due to their complementary and unique properties, mainly including hexagonal boron nitride (h-BN), molybdenum disulfide (MoS
2 ), metal organic frameworks (MOF), carbon nitride (CN), titanium carbide (MXene) and black phosphorene (BP). In this review, except for graphene, the flame retardant mechanism involving different layered nanomaterials are also reviewed. Meanwhile, the functionalization method and flame retardancy effect of different layered nanomaterials are emphatically discussed for offering an effective reference to solve the fire hazards of polymer materials. Moreover, this work objectively evaluates the practical significance of polymer/layered nanomaterials composites for industrial application. [ABSTRACT FROM AUTHOR]- Published
- 2021
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5. A Good Dry Powder to Suppress High Building Fires
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Zong Ruowen, Gao Jiaxin, Liu Hai-qiang, Hu Yuan, and Lo Siuming
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Materials science ,Waste management ,Magnesium ,Metallurgy ,high buildings ,chemistry.chemical_element ,Fire safety ,General Energy ,chemistry ,Dry powder ,Halon substitutes ,Fire protection ,fire suppressant ,Lower cost ,magnesium hydroxide - Abstract
In our daily life there are more and more super high buildings and now their fire safety have been paid more attention. Thence, a new material, magnesium hydroxide (Mg(OH)2) was introduced and its possible application was discussed in this paper in order to protect constructions better. It was analyzed at three aspects including its advantages, physical and chemical properties and fire suppression effectiveness. Mg(OH)2 powder is better because it is cleaner, more efficient and lower cost of production, store and transportation. A comparison of physical and chemical properties between magnesium compounds and other common commercial fire suppressant proved that Mg(OH)2 powder absorbed more heat when they decomposed. In a bench-test, the Mg(OH)2 powder is also more efficient than the common commercial BC powder and ABC Powder. The results have proved that Mg(OH)2 powder is a kind of good, clean and high efficient powder to suppress tall building fires.
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- 2014
6. Synergistic effects of core-shell structured piperazine pyrophosphate microcapsules on fire safety and mechanical property in styrenic thermoplastic elastomer.
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Zhu, Min, Jia, Pengfei, Yang, Guisheng, Song, Lei, Hu, Yuan, and Wang, Bibo
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FIRE prevention , *THERMOPLASTIC elastomers , *FIREPROOFING agents , *PIPERAZINE , *FIRE resistant polymers , *HEAT release rates , *UREA-formaldehyde resins , *CARBON nanotubes , *MELAMINE-formaldehyde resins - Abstract
[Display omitted] • A core-shell structured piperazine pyrophosphate microcapsules (MT@PAPP) is constructed. • The MT@PAPP enhances the compatibility and mechanical property of TPE/MT@PAPP composites. • Compared with pure TPE, the PHRR and PSPR of TPE/MT@PAPP were reduced by 78.5% and 60.0%, respectively. In this study, core-shell structured piperazine pyrophosphate (PAPP) is designed to enhance the fire safety and mechanical property of styrenic thermoplastic elastomer (TPE) composites. The PAPP is microencapsulated with carbon nanotube modified melamine-formaldehyde resin to prepare core-shell structured flame retardants (MT@PAPP). Due to the excellent compatibility between the MT@PAPP and TPE matrix, the mechanical property of TPE/MT@PAPP is improved. Compared with TPE, the peak heat release rate and peak smoke production rate of TPE/MT@PAPP are decreased by 78.5% and 60.0%, respectively. Thus, the core-shell structured piperazine pyrophosphate microcapsule strategy provides an excellent approach to obtain high-performance TPE composites. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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7. Multilayer joule heating and electromagnetic interference shielding composite fabric with high interfacial durability.
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Wang, Bibo, Jia, Pengfei, He, Ruofan, Song, Lei, and Hu, Yuan
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ELECTROMAGNETIC shielding , *ELECTROMAGNETIC interference , *COTTON fibers , *WRIST joint , *COTTON textiles , *NANOWIRES , *ELECTROTEXTILES - Abstract
[Display omitted] • The AgNW-10-W cotton fabric were prepared by dip-coating technology. • The AgNW-10-W cotton fabric shows the EMI SE as high as 53.9 dB with thickness of 1.3 mm. • The AgNW-10-W cotton fabric can reach 76 °C under 2 V applied voltage in 60 s. • AgNW-10-W cotton fabric exhibits excellent bending and salt water resistance. • The pHRR of AgNW-10-W cotton fabric are reduced by 31.3%. High-performance modern integrated intelligent wearable electronic textiles show excellent joule heating performance, electromagnetic interference shielding (EMI) and fire safety. In this work, cotton fabric as a biomass material is used as the framework. Due to its strong electrostatic interaction and hydrogen bonding, 3‑aminopropyl trethoxy silane (KH550) layer, silver nanowire (AgNW) conductive network and water-based polyurethane (WPU) protective layer are formed on the surface of cotton fiber for fabricating composite fabric (AgNW-10-W). Due to the perfect collaborative conductive network and porous fiber network structure, AgNW-10-W shows excellent EMI shielding effectiveness (53.9 dB, 1.3 mm thickness). Furthermore, the surface temperature of the joule heating composite fabric with AgNW as the conductive raw material can reach over 100 °C at an applied voltage of 2 V. Meantime, the composite fabric also shows good cycling and long-term joule heating performance. In the wear tests, the AgNW-10-W cotton fabric has good bending resistance and salt water resistance. It produces heat evenly on the human body's wrist joint and has a certain wear function. In the combustion performance test, the pHRR of AgNW-10-W cotton fabric was 31.3 % lower than that of pure cotton fabric. The work demonstrates the appeal of high-performance multifunctional electronic textiles for joule heating, electromagnetic shielding, and fire safety applications in AI and emerging wearable electronics. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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8. Flame-retardant in-situ formed gel polymer electrolyte with different valance states of phosphorus structures for high-performance and fire-safety lithium-ion batteries.
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Li, Xingjun, Li, Zhirui, Zhang, Weijie, Jiang, Xin, Han, Longfei, Wang, Xiaodong, Kan, Yongchun, Song, Lei, and Hu, Yuan
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POLYELECTROLYTES , *POLYMER colloids , *LITHIUM-ion batteries , *ACRYLATES , *FIREPROOFING agents , *PHOSPHORUS , *ENERGY storage - Abstract
• The fire-proof TD-GPE with + 3 and + 5 phosphorus valence states was synthesized via in-situ polymerization. • The TD-GPE shows highly stable cycle performance for NCM811 and LFP full soft pack batteries (1 Ah). • The "jet fire" and leakage were suppressed in the thermal abuse test of NCM811 battery by using flame-retardant TD-GPE. Lithium-ion batteries (LIBs) have been widely used today owing to portability, high energy storage, and reusability. However, commercial liquid electrolytes in LIBs possess intensive mobility and terrible flammability. Accordingly, leakage, combusting, and even exploding can frequently occur when LIBs work under abuse conditions. Herein, a novel flame-retardant gel polymer electrolyte (GPE) containing + 3 and + 5 phosphorus valence states of phosphorus structures was designed by in-situ thermal polymerization of tri(acryloyloxyethyl) phosphate (TAEP), diethyl vinylphosphonate (DEVP), and pentaerythritol tetraacrylate in electrolytes. After being ignited by fire, this GPE extinguished quickly with a combusting time of only 0.9 s, showing much lower flammability. Besides, the GPE is compatible with graphite anode, LiFePO 4 (LFP), and even LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathodes. The as-assembled LFP and NCM811-based pouch cells (1 Ah-type) with TD-GPE achieved stable cycling, maintaining 88.52 % and 95.2 % of the initial capacities, respectively after 200 and 190 cycles at 0.5C. Moreover, the as-prepared TD-GPE dramatically reduced the fire hazard of NCM811 batteries without sacrificing the electrochemical performance. The thermal abuse test demonstrates that the leakage and combustion of NCM811||TD-GPE||Graphite pouch cell could be significantly suppressed in the test process, indicating that battery safety improves significantly via the combined use of different phosphorus valence structures. This is because the + 5 phosphorus valence of TAEP promoted the formation of carbon layers, and the + 3 phosphorus structure in DEVP captured free radicals by quenching effect. This work paves a different path for designing safe and high-performance GPEs in LIBs based on gaseous-phase and condensed-phase mechanisms. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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9. Unlocking anti-aging potential: Flame retardants thrive without added antioxidants.
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Sun, Pengfei, Jia, Pengfei, Wang, Wei, Hong, Ningning, Yu, Fuhao, Chen, Dayong, Wang, Bibo, Gui, Zhou, and Hu, Yuan
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FIREPROOFING agents , *AGING prevention , *HEAT release rates , *FIRE prevention , *ETHANOLAMINES , *VINYL acetate , *ANTIOXIDANTS - Abstract
A synergistic flame retardant with a core-shell structure utilizes the 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) derivative as the outer shell and ammonium polyphosphate (APP) as the inner core. Three derivatives of DOPO (DOPO-GY, DOPO-DH and DOPO-GD) are synthesized by reacting DOPO with glyoxal, paraformaldehyde and diethanolamine, and glutaraldehyde, respectively. DOPO-GY@APP, DOPO-DH@APP and DOPO-GD@APP exhibit good radical scavenging activities. The oxidation induction time for EVA/DOPO-GY@APP is exceptionally high at 19.04 min, in contrast to EVA alone, which has an induction time of only 5.51 min. Simultaneously, after aging at 180 °C and 165 °C for 7 days, the retention rates of elongation at break for EVA/DOPO-GY@APP are 34.67 % and 55.50 %, respectively. These findings demonstrate the long-term anti-aging properties of EVA/DOPO-GY@APP without the need for additional antioxidants. Moreover, EVA/DOPO-GY@APP, EVA/DOPO-DH@APP and EVA/DOPO-GD@APP all achieve V-0 rating with 25 % addition of flame retardant. In comparison to pure EVA, their peak heat release rates and maximum smoke density decrease by 52 % and 47 %, 43 % and 54 %, and 51 % and 44 %, respectively. Additionally, compared to EVA/APP, their mechanical properties have been improved. Therefore, these microencapsulated flame retardants with DOPO derivatives as the shell effectively enhance the mechanical properties and fire safety of EVA composites. [Display omitted] • A multifunctional microencapsulated flame retardant is successfully designed. • The DOPO-GY@APP shows good radical scavenging activities. • The retention rate of EB from EVA/DOPO-GY@APP can reach 55.50 % after aging at 165 °C for 7 days. • EVA/DOPO-GY@APP reveal anti-aging properties without adding any antioxidant. • The pHRR and Ds max of EVA/DOPO-GY@APP are reduced by 52 % and 47 %, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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10. Double-shell microstructures based on thermochromic materials and biomass flame retardants towards solving the fire and icing hazards.
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Lin, Bicheng, Cai, Wei, Qi, Liangyuan, Cui, Tianyang, Li, Zhaoxin, Ziaur Rahman, Mohammad, Fei, Bin, Hu, Yuan, and Xing, Weiyi
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FIRE resistant polymers , *FIREPROOFING agents , *FIREPROOFING , *EXTREME weather , *COMPOSITE coating , *PROTECTIVE coatings , *HAZARDS - Abstract
[Display omitted] • A flame-retardant and photo-thermal microstructure is synthesized. • Thermochromic materials and bio-based flame retardants are used as core and shell. • Heat release and smoke production are effectively suppressed. • The melting and slide of ice block is accelerated by solar-thermal conversion. Due to the extreme dynamic weather, important industrial facilities and infrastructure providing vital support for people's lives usually face the hazards of fire and icing, especially in the weather of thunderstorm and ice. Therefore, to further establish a safe community, we develop a dual-functional polyurea (PUA) coating used as protective materials by introducing flame retardancy and solar de-icing performance. Based on the microencapsulation and electrostatic self-assembly technologies, flame-retardant and thermochromic microcapsules (TCM) are firstly prepared and then added into PUA resin, by using melamine resin and bio-based phytic acid/chitosan (PA/CS) hybrids as double-shell materials. The high phosphorus content of PA and the carbon-forming effect of CS together play a synergistic flame retardant effect, not only improving the thermal stability of microcapsules but also enhancing the flame retardant property of PUA coating. In the cone calorimetry test, the ignition time of TCM@PA/CS@PUA-3 is longer, and the pHRR is reduced by 19.93 %, which shows the improvement of flame retardant performance. Due to the thermochromic mechanism, TCM@PA/CS@PUA composite coatings are able to adjust the photo-thermal conversion ability according to different environment temperature, achieving less temperature in hot environment and higher temperature in cold environment. The excellent photo-thermal conversion ability also promotes the ice melting and slide in 525 s. This polyurea composite coating with both flame retardant and de-icing properties shows great potential for maintaining the normal operation and safety of outdoor industrials and infrastructure in extremely dynamic weather conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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11. Bio-based and fireproof radiative cooling aerogel film: Achieving higher sustainability and safety.
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Cai, Wei, Lin, Bicheng, Qi, Liangyuan, Cui, Tianyang, Li, Zhaoxin, Wang, Junling, Li, Sicheng, Cao, Chengfei, Ziaur Rahman, Mohammad, Hu, Xin, Yu, Rujun, Shi, Shuo, Xing, Weiyi, Hu, Yuan, Zhu, Jixin, and Fei, Bin
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AEROGELS , *FIREPROOFING , *FIRE resistant polymers , *FIREPROOFING agents , *TEMPERATURE control , *FIRE prevention , *PHYTIC acid - Abstract
[Display omitted] • This work focuses on the sustainability and safety of radiative cooling materials. • Bio-based chitosan and phytic acid are used to prepare radiative cooling film. • The radiative cooling effect and fireproof performance are presented simultaneously. Even though significant advantages in the energy-free regulation of temperature are presented, the practical applications of radiative cooling materials in buildings and human surfaces still involve many safety issues, especially for fire hazards of polymer-based materials. Meanwhile, renewable and environmentally friendly materials are urgently needed to develop suitable radiative cooling materials with no adverse environmental impact. Herein, a chitosan-derived composite aerogel film with high solar reflection provided by the addition of melamine-phytic acid (MA/PA) hybrids is designed and prepared, presenting radiative cooling and fireproof performances. The instinct deep-yellow color of chitosan (CS) is successfully shielded by high-reflective MA/PA hybrids, while IR emissivity of up to 90.4 % and solar reflectivity of ∼ 89.3 % are achieved. In outdoor environments, this composite aerogel shows sub-ambient temperature drops of ∼ 4.3 °C and ∼ 3.1 °C in cloudless and cloudy weather, presenting a robust cooling effect. In addition, CS-MA/PA composite aerogel film with 3 mm thickness can isolate the fire of ∼ 500 °C, showing superior fire safety attributed to the synergistic flame retardant effects among chitosan, phytic acid, and melamine, which suppress the initial growth of fire and promote the rapid formation of protective char layer. This work provides a bio-based, fire-safe, and radiative cooling material to decrease the energy consumption of temperature regulation with a more environmentally friendly and safer approach, further promoting the practical application of radiative cooling materials. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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12. Construction of MXene-mediated inorganic-organic quaternary ammonium salt-hybrid coating for fire safety and multi-mode synergistic antibacterial of cotton fabric.
- Author
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Wu, Ruiying, Jia, Pengfei, Song, Lei, Li, Jinhu, Wang, Bibo, and Hu, Yuan
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COTTON , *COTTON textiles , *FIRE prevention , *ESCHERICHIA coli , *TRANSITION metal carbides , *MEDICAL electronics , *AMMONIUM salts , *NATURAL dyes & dyeing - Abstract
With the continuous development of the society, there is a growing demand for the durability, versatility and multifunction of cott fabrics. In this work, the cotton fabric is coated with multifunctional coating via dip-coating of transition metal carbide (MXene) and then encapsulation of dimethyloctadecyl [3-trimethoxysilopropyl] ammonium chloride (QAS). In view of MXene with excellent light absorption and photothermal conversion efficiency, the controllable antibacterial performance of the cotton fabric is further improved. Benefiting from the encapsulation of QAS, CF@P@M@QAS fabric shows mechanical stability (24 h washing, 1000 cycles folding test and 100 cyclic abrasion) and hydrophobicity. Meantime, the QAS on the surface of multifunctional cotton fabric significantly increases antibacterial activity, and the antibacterial rate can reach to 100 % against Staphylococcus aureus (S. aureus) and 98 % Escherichia coli (E. coli). Besides, CF@P@M@QAS cotton fabric also integrates functions of fire safety and physical therapy. Thus, this multifunctional cotton fabric based MXene offers a novel solution for extending its application in medical electronics and physical therapy. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2024
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13. Intelligent polyester fabric with fire safety for personal temperature management.
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Qi, Liangyuan, Chen, Liang, Cai, Wei, Wang, Chuanshen, Wang, Bangyu, Hu, Yuan, and Xing, Weiyi
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FIRE prevention , *FIREPROOFING , *ATTENUATED total reflectance , *TEMPERATURE control , *HEAT release rates , *GRAPHITIZATION - Abstract
• The smart fabric cotaing was prepared using a one-step process. • A solid, fire-resistant gel serves as the host skeleton. • A solid–liquid switchable phase change functional guest. • The fabric effectively responds to changes in ambient temperature. The stability of personal thermal management are increasingly indispensable in modern society due to the growing demand for energy savings and environmental protection. Herein, inspired by solid–liquid host–guest materials, we propose a coating preparation strategy that uses a solid flame-retardant gel as the host skeleton filled by a solid–liquid switchable phase change flame-retardant functional guest, thus fabricating smart polyester fabrics for personal temperature management in one step. Both attenuated total reflectance (ATR) and scanning electron microscopy (SEM) are used to confirm the host–guest structure coating on the surface of polyester fabric. Results from simulated cold and heating environments show that the coated polyester fabric has a desirable personal temperature regulation ability. The skin wrapped by the coated polyester fabric presents a higher temperature compared with bare polyester fabric, in simulated cold conditions. Meanwhile, in heating conditions, the internal temperature of the coated polyester fabric is 5.2 oC lower than that of the bare polyester fabric. Furthermore, the coated polyester fabric exhibits excellent flame retardancy in the combustion test, with a horizontal burning rate of 85.7 mm/min and a peak of heat release rate (PHRR) reduction of 52.8 %, attributed to higher graphitization degree and suppressed pyrolysis products. For promoting the practical application, the water vapor transmission, washing resistance, and mechanical performance are also deeply studied. Hence, a phase-change flame-retardant polyester fabric constructed with a host–guest structure provides huge application potentials in various personal temperature management fields, such as snow rescue, field camping, and adventure activities. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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14. Multifunctional Additive: A novel regulate strategy for improving mechanical property, aging life and fire safety of EVA composites.
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Jia, Pengfei, Yu, Fuhao, Tao, Youji, Sun, Pengfei, Xing, Weiyi, Jie, Ganxin, Hu, Yuan, and Wang, Bibo
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VINYL acetate , *FIRE prevention , *AGE , *HEAT release rates , *FIREPROOFING agents , *ETHYLENE-vinyl acetate - Abstract
[Display omitted] • A multifunctional additive (MCMH) is carefully designed. • The microencapsulation technology improves the compatibility between MCMH and XLEVA. • The OIT value of XLEVA/MCMH was basically unchanged after extracted for 5 days. • The retention of EB of XLEVA/MCMH could reach 71.8% after aging at 165 °C for 14 days. • The PHRR and Ds max of XLEVA/MCMH are reduced by 89.4% and 53.6%, respectively. A multifunctional additive is carefully designed for crosslinked ethylene–vinyl acetate copolymer (XLEVA) composites to improve their mechanical properties, aging resistance and fire safety. In this study, first, a layer of silica was microencapsulated on magnesium hydroxide to give a large amount of hydroxyl group on the magnesium hydroxide surface; second, the primary antioxidant 3-(3, 5-di- tert -butyl-4 hydroxyphenyl) propionicacid was grafted on SiMH surface to prepare antioxidant microencapsulated flame retardants (MCMH). Compared with the pure XLEVA, the peak heat release rate and the maximum smoke density of flame retardant XLEVA/MCMH are decreased by 89.46% and 53.6%, respectively. Moreover, these oxidation induction time values of XLEVA/MH/AO and XLEVA/SiMH/AO decreased sharply after extracted for 1d. However, the OIT value of XLEVA/MCMH was basically unchanged after extracted for 5d. After aging at 165 °C for 14 days and γ-ray irradiation dose of 500 kGy, the retention of elongation at break could reach 71.8% and 86.6%, showing excellent aging resistance. These results show that MCMH has a good synergistic effect for enhancing the flame retardant, mechanical property as well as aging resistance of XLEVA composites. The "Killing three birds with one stone" strategy provides an excellent solution for obtaining high-performance XLEVA cable materials. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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15. Synthesis of a hyperbranched phosphorus-containing polyurethane as char forming agent combined with ammonium polyphosphate for reducing fire hazard of polypropylene.
- Author
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Zhang, Tao, Tao, Youji, Zhou, Feng, Sheng, Haibo, Qiu, Shuilai, Ma, Chao, and Hu, Yuan
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POLYPHOSPHATES , *FIREPROOFING agents , *HEAT release rates , *CHAR , *POLYURETHANES , *POLYPROPYLENE , *ENTHALPY - Abstract
Due to the inherent flammability of polypropylene (PP), it is limited in the application of flame retardant materials. In this work, a novel char forming agent, hyperbranched phosphorus-containing polyurethane (HPPU), was synthesized and used as efficient char forming agent. When ammonium polyphosphate (APP) was combined with HPPU, APP/HPPU endow PP significantly improved flame retardancy than single APP. Although the total carbon monoxide production (TCOP) of some PP/APP/HPPU composites is higher than that of PP/APP composite, it is still lower than that of neat PP. LOI (limited oxygen index) and UL-94 tests reveal that PP composites with 25 wt% HPPU/APP with ratio of 4:1 are able to reach 27 vol% and V-0 rating, respectively. The addition of 25 wt% APP/HPPU with ratio of 2:1 into PP can result in decrease in peak heat release rate of about 72%, decrease in total heat release of about 38% and decrease in TCOP of about 93%. APP/HPPU promotes PP to form more stable, compact, and continuous char layer which effectively hinder heat and oxygen transfer and protect the inner matrix from decomposition. Thermogravimetric-infrared results reveal that the gas phase flame retardant mechanism of APP/HPPU is the dilution effect of ammonia from APP and the flame inhibition effect of phosphorus-containing species from HPPU. Image 1 • A novel hyperbranched phosphorus-containing polyurethane (HPPU) is firstly synthesized. • LOI and UL-94 tests revealed that the addition of 25 wt % HPPU/APP into neat PP was able to reach 27 % and V-0 rating. • APP/HPPU exhibit remarkable flame retardant and carbon monoxide (CO) suppression to PP composites. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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16. Construction of multifunctional boron nitride nanosheet towards reducing toxic volatiles (CO and HCN) generation and fire hazard of thermoplastic polyurethane.
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Wang, Junling, Zhang, Yan, Cai, Wei, Yao, Congxue, Hu, Yuan, Hu, Weizhao, and Zhang, Dichang
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BORON nitride , *PHYTIC acid , *POLYPYRROLE , *THERMOPLASTICS , *TENSILE tests - Abstract
Graphical abstract Highlights • The multifunctional boron nitride nanosheet (CPBN) is firstly constructed. • Obvious decrease in peak heat release rate is achieved by incorporating CPBN. • Dramatic suppressions on smoke and toxic volatiles releases are found by adding CPBN. • Improved mechanical performance is obtained after the inclusion of CPBN. Abstract Considerable toxic volatiles (CO and HCN) generation and high fire hazard has definitely compromised the application of thermoplastic polyurethane (TPU). Here, a novel functionalization strategy for bulky h-BN is adopted to obtain the multifunctional CPBN, aiming at the flame retardancy reinforcement of TPU. The multifunctional CPBN is successfully prepared via the wrapping of phytic acid doped polypyrrole shell, following with the adsorption of copper ions. The obviously decreased peak heat release rate, peak smoke production rate and total smoke production values, obtained from cone test, confirms the reduced fire hazard of TPU composite with CPBN. The dramatic suppressions on CO and HCN releases can also be observed from TG-IR test. Tensile test demonstrates that adding CPBN favors the reinforcement in mechanical property of TPU. Thus, the concurrent improvements in flame retardancy and mechanical performance are achieved by incorporating CPBN. This work opens up new avenues for the functionalization of h-BN, and thus facilitates its promising applications in polymer-matrix composite. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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17. Ultra-thin, non-combustible PEO polymer solid electrolyte for high safety polymer lithium metal batteries.
- Author
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Liu, Yongyu, Han, Longfei, Liao, Can, Yu, Heng, Kan, Yongchun, and Hu, Yuan
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SUPERIONIC conductors , *SOLID electrolytes , *POLYELECTROLYTES , *LITHIUM cells , *ETHYLENE oxide , *FLAMMABLE liquids - Abstract
• PF 6 − endow the PEO solid electrolyte an excellent flame-retardant performance. • Ionic liquids act as flame retardants and also facilitate to form robust SEI. • COMSOL Multiphysics is used to simulate lithium-ion deposition. • The combustion process of SSE was analyzed by genetic algorithm and experiment. • A new instrument is used to evaluate battery combustion performance. The safety problems of lithium-ion batteries (LIBs) have aroused great concern on account of their extensive use. It is believed that the replacement of flammable liquid electrolytes with solid electrolytes (SSE) will solve this problem and provide an unmatched energy density for lithium-based batteries. Here, Lithium hexafluorophosphate (LiPF 6) and ionic liquid serve as flame retardants for Poly (ethylene oxide) (PEO) solid electrolytes with Polyamide 6 (PA6) membrane as the skeleton. PA membrane can not only decrease the crystallinity of PEO to facilitate lithium-ion migration, but also inhibit the growth of lithium dendrites, which is attributed to its lithium-philic properties, adequate mechanical properties and flexibility. In addition, the increase of ionic liquid, on the one hand, can provide hexafluorophosphoric acid ions, which endow the SSE with excellent flame-retardant performance. The electrolyte exhibits self-extinguishing properties after ignition. On the other hand, the ionic liquid can protect the lithium anode and develop a robust SEI, thus giving the battery smooth long-cycle performance (Capacity retention rate at 1800th cycle: 89.06%). The innovative design idea of developing high-powered LIBs by introducing low-cost PA6 membranes into all solid compounds is appealing, and it can also be expanded to a combination of assorted polymers to encounter the requirements of a variety of batteries. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
18. Design of reduced graphene oxide decorated with DOPO-phosphanomidate for enhanced fire safety of epoxy resin.
- Author
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Shi, Yongqian, Yu, Bin, Zheng, Yuying, Yang, Jian, Duan, Zaipeng, and Hu, Yuan
- Subjects
- *
GRAPHENE oxide , *EPOXY resins , *FIREPROOFING agents , *POLYETHYLENEIMINE , *COMBUSTION - Abstract
A facile approach was developed to simultaneously functionalize and reduce graphene oxide (GO) with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-phosphonamidate. To achieve stable dispersion and effective stress transfer, graphene was functionalized by polyethyleneimine (PEI). To improve the fire resistance of bare graphene, DOPO was grafted on the surface of PEI-reduced graphene oxide (PEI-rGO) to obtain the grafting of DOPO-phosphonamidate on the graphene. A morphological study indicated that, due to the good interfacial interaction between the functionalized graphene and epoxy (EP), functionalized reduced graphene oxide (f-rGO) was well-dispersed in the host polymer. Incorporation of 3.0 wt% f-rGO led to the increased char yields of the EP. Moreover, the storage modulus and glass transition temperature were improved, respectively. The evaluation of combustion behavior demonstrated that the peak heat release rate and total heat release of f-rGO/EP were reduced by 31% and 34.3%, respectively, compared to those of neat EP. This dramatically reduced fire hazards were mainly attributed to the synergistic effect of f-RGO. On one hand, DOPO-phosphonamidate on the surface of GO promoted flame inhibition in the gas phase while protecting the rGO against fire. On the other hand, the adsorption and barrier effect of rGO inhibited the heat and gas release, respectively, promoting the formation of graphitized carbons. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
19. Construction of multifunctional MoSe2 hybrid towards the simultaneous improvements in fire safety and mechanical property of polymer.
- Author
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Wang, Junling, Ma, Chao, Mu, Xiaowei, Cai, Wei, Liu, Longxiang, Zhou, Xia, Hu, Weizhao, and Hu, Yuan
- Subjects
- *
MOLYBDENUM selenides , *MECHANICAL properties of polymers , *POLYURETHANES , *CHEMICAL reactions , *CHAIN scission - Abstract
Organic modification of MoSe 2 sheets is firstly achieved by Atherton–Todd reaction, aiming at the acquisition of multifunctional MoSe 2 hybrid. Simultaneous enhancements in fire safety and mechanical property of thermalplastic polyurethane (TPU) are obtained with the presence of this hybrid. Strong interfacial interactions between the functionalized MoSe 2 sheets and TPU can be obtained, making more efficient load transfer from the weak polymer chains to the robust sheets. Besides, more coherent barrier network may be formed in polymer matrix, restraining the diffusion of decomposed fragments and reducing the supply for combustion fuel. Consequently, the decreases in heat release are observed for polymer composites. Notably, the releases of toxic gases, such as HCN and CO, are also suppressed by this barrier network, resulting in the reductions in fire toxicity. This work may open a new door for the functionalization of MoSe 2 sheets and evoke significant developments in its promising applications. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
20. Mussel-inspired functionalization of electrochemically exfoliated graphene: Based on self-polymerization of dopamine and its suppression effect on the fire hazards and smoke toxicity of thermoplastic polyurethane.
- Author
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Cai, Wei, Wang, Junling, Pan, Ying, Guo, Wenwen, Mu, Xiaowei, Feng, Xiaming, Yuan, Bihe, Wang, Xin, and Hu, Yuan
- Subjects
- *
ELECTROCHEMICAL analysis , *GRAPHENE , *POLYMERIZATION , *DOPAMINE , *POLYURETHANES , *THERMOPLASTIC composites - Abstract
The suppression effect of graphene in the fire hazards and smoke toxicity of polymer composites has been seriously limited by both mass production and weak interfacial interaction. Though the electrochemical preparation provides an available approach for mass production, exfoliated graphene could not strongly bond with polar polymer chains. Herein, mussel-inspired functionalization of electrochemically exfoliated graphene was successfully processed and added into polar thermoplastic polyurethane matrix (TPU). As confirmed by SEM patterns of fracture surface, functionalized graphene possessing abundant hydroxyl could constitute a forceful chains interaction with TPU. By the incorporation of 2.0 wt % f-GNS, peak heat release rate (pHRR), total heat release (THR), specific extinction area (SEA), as well as smoke produce rate (SPR) of TPU composites were approximately decreased by 59.4%, 27.1%, 31.9%, and 26.7%, respectively. A probable mechanism of fire retardant was hypothesized: well-dispersed f-GNS constituted tortuous path and hindered the exchange process of degradation product with barrier function. Large quantities of degradation product gathered round f-GNS and reacted with flame retardant to produce the cross-linked and high-degree graphited residual char. The simple functionalization for electrochemically exfoliated graphene impels the application of graphene in the fields of flame retardant composites. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
21. A facile strategy to simultaneously exfoliate and functionalize boron nitride nanosheets via Lewis acid-base interaction.
- Author
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Cai, Wei, Hong, Ningning, Feng, Xiaming, Zeng, Wenru, Shi, Yongqian, Zhang, Yi, Wang, Bibo, and Hu, Yuan
- Subjects
- *
BORON nitride , *GRAPHITE , *NUCLEOPHILIC reactions , *NITROGEN , *X-ray diffraction - Abstract
The structure of hexagonal boron nitride (h-BN) is similar to that of graphite and its practical application in polymer composites is blocked by incompatible surface nature. Here, we presented a facile method to simultaneously exfoliate and organically modify h-BN nanosheets with Lewis acid-base interaction. Due to the affinity of the nitrogen atoms, the synthesized nucleophilic flame retardant (Lewis bases) bonded with boron atoms of h-BN nanosheets (Lewis acids) and facilitated the direct exfoliation of bulk h-BN. The structure and morphology of flame retardant functionalized BN (f-BN) nanosheets were well characterized. Then performances of f-BN nanosheets as advanced nanofillers in TPU composites were investigated deeply. As confirmed by SEM, XRD, and TEM, f-BN nanosheets were well-dispersed in the TPU matrix and formed strong interfacial interaction with the polymer matrix. The dramatic barrier effect of f-BN nanosheets and intrinsic flame retardant of synthesized phosphonated polyethyleneimine (P-PEI) significantly improved thermal stability, fire safety, and smoke suppression of TPU composites. By adding 5.0 wt% f-BN nanosheets, the maximum mass loss rate, peak heat release rate (pHRR), and smoke produce rate (SPR) were decreased by 20.8 %, 68.0%, and 53.6%, respectively. Moreover, the mechanical properties of TPU composites were enhanced. The self-stiffen effect of TPU composites was successfully achieved: after 108 k dynamic compressive cycles, the storage modulus of TPU/f-BN-5.0 exhibits a 13.8% increase. Based on Lewis acid-base interaction, designing a nucleophilic flame retardant to simultaneously exfoliate and functionally modify h-BN nanosheets offers a promising avenue for the preparation of functionalized BN nanosheets, thus broadening its practical application in the polymer material field. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
22. Self-assembly of zinc hydroxystannate on amorphous hydrous TiO2 solid sphere for enhancing fire safety of epoxy resin.
- Author
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Wang, Wei, Kan, Yongchun, Liu, Jiajia, Liew, Kim Meow, Liu, Lei, and Hu, Yuan
- Subjects
- *
MOLECULAR self-assembly , *ZINC hydrides , *TITANIUM dioxide , *EPOXY resins , *AMORPHOUS alloys , *X-ray diffraction - Abstract
Zinc hydroxystannate (ZHS) was fabricated on the surface of amorphous hydrous TiO 2 solid spheres (AHTSS) via a layer-by-layer method for improving the fire safety of epoxy resin. AHTSS@PEI@ZHS was prepared by self-assembly of AHTSS, PEI and ZHS. The well-organized fabrication process was proved by TEM, XPS, XRD and SEM tests. TG results illustrated that the incorporation of AHTSS@PEI@ZHS show a higher residue compared with the addition of AHTSS or ZHS alone. In addition, AHTSS@PEI@ZHS filled EP composites exhibits improved flame retardancy and smoke suppression properties evaluated by cone calorimeter test. TG-IR results also indicated that the catalytic labyrinth structure of AHTSS@PEI@ZHS can effectively decrease the permeation of volatile organic compounds, thereby improving the fire safety of EP resin. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
23. Economical and environment-friendly synthesis of a novel hyperbranched poly(aminomethylphosphine oxide-amine) as co-curing agent for simultaneous improvement of fire safety, glass transition temperature and toughness of epoxy resins.
- Author
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Ma, Chao, Qiu, Shuilai, Yu, Bin, Wang, Junling, Wang, Chengming, Zeng, Wenru, and Hu, Yuan
- Subjects
- *
BRANCHED polymers , *CURING , *FIRE prevention , *GLASS transition temperature , *CHEMICAL synthesis , *EPOXY resins - Abstract
Epoxy resins inherently suffer flammability and brittleness. Various approaches have been used to improve their fire safety or toughness, however, glass transition temperature ( T g ) is always deteriorated concomitantly. Herein, a novel hyperbranched poly(aminomethylphosphine oxide-amine) (HPAPOA) was synthesized from α -aminomethylation reaction of trihydroxymethylphosphine (THP) with piperazine before oxidation. THP was prepared from tetrakis(hydroxymethyl)phosphonium sulfate and barium hydroxide to avoid complex purification in the synthesized process. When HPAPOA was utilized as co-curing agent for epoxy resins, T g and impact strength of epoxy thermosets are improved due to the increased cross-linking density and the multiple toughening mechanisms. Simultaneously, fire safety include flame retardancy, smoke suppression and toxicity reduction is raised (except 1.0 wt% added). The condensed phase flame retardant mechanism is verified as increased char yield and protective and barrier effect of the formed char layer and the gas phase for release of phosphorus-containing species of HPAPOA. With as low as 3.0 wt% HPAPOA incorporated, epoxy thermoset achieved vertical burning V-0 rating with a limited oxygen index of 30.7%. The blowing-out effect for upgradation of vertical burning rating is elucidated. Moreover, the curing reactivity of epoxy systems is slightly changed and the reaction activation energy is elevated. The thermal decomposition temperature of epoxy thermoset diminishes. With 2.0 wt% HPAPOA added, tensile and flexural properties are improved and those with other contents are slightly depressed. The practical HPAPOA modified epoxy thermosets with obvious disadvantage conquered and higher T g can be used in industries for high-performance applications. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
24. Intrinsic ionic confinement dynamic engineering of ionomers with low dielectric-k, high healing and stretchability for electronic device reconfiguration.
- Author
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Wang, Jingwen, Zheng, Yapeng, Ren, Wei, Ang, Edison Huixiang, Song, Lei, Zhu, Jixin, and Hu, Yuan
- Subjects
- *
IONOMERS , *ELECTRONIC equipment , *FIREPROOFING agents , *HEAT release rates , *FLEXIBLE electronics , *ENGINEERING - Abstract
• An ionic confinement engineering approach is proposed to facilitate dynamic ionic crosslinking. • The ionomers deliver low dielectric-k property, high stretchability and fast self-healing capability. • The EGaIn-infused stretchable device is designed for electronic device reconfiguration. Ionomers are gaining much attention in the fields of soft robots, flexible electronics, and artificial intelligence. However, intrinsic dynamics modulation of ionomer molecules to achieve desirable properties is highly required and challenging due to a lack of understanding of the interactions between polymerics and ionic species. In this study, a novel ionic confinement engineering approach was employed, in which the composition of a copolymer, namely, PTAE-Fe, was adjusted to facilitate dynamic ionic crosslinking, which enables high stretchability (>10000 % elongation). The proportion of ionic functional groups in PTAE-Fe significantly enhanced the self-healing efficiency up to 95 %. The ionic confinement strategy also promotes electron momentum locking, resulting in a low dielectric-k property (D k < 2.5), while a reduction in the heat release rate of 69.1 % makes the ionomer an excellent flame retardant material. In addition, a eutectic gallium-indium (EGaIn)-infused stretchable device and low D k flexible ink were designed according to the ionic confinement strategy. The as-fabricated ionomer is expected to benefit a wide range of energy and storage technologies. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
25. Electrochemical diazo sulfonated black phosphorus toward conceptual isolation structure with high air stability and fire safety.
- Author
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Qiu, Shuilai, Zhou, Xia, Chu, Fukai, Zhang, Yan, Yang, Wenhao, Wang, Xin, and Hu, Yuan
- Subjects
- *
CONCEPTUAL structures , *FIRE prevention , *HEAT release rates , *GLASS transition temperature , *PHOSPHORUS , *MICROSPHERES - Abstract
The dispersion problems of black phosphorus (BP) in polymer-based composites can be solved by designing isolation structure. An isolating structural material with functionalized BP nanosheets and polystyrene (PS) microspheres was prepared by molding method. Firstly, the sulfonated BP nanosheets with negative charge were obtained by electrochemical diazo modification (electrochemical diazo modification of BP is first report, and achieved good synchronous stripping and modification effect). The sulfonated BP and the PS microspheres with positive charge were self-assembled to form composite microspheres through strong electrostatic interaction. The prepared composite microspheres were further hot pressed near the glass transition temperature to selectively distribute the BP nanosheets at the interface of the fused PS microspheres. Therefore, the PS-BP isolation structure with uniform dispersion and reasonable distribution was obtained in the PS matrix. Thanks to this unique structure, the maximum heat release rate and smoke production rate reduction of the isolation structure can reach 50.1% and 43.3%, which at an excellent level in the same kind of two-dimensional material based composites. The tensile strength is maximally increased by 71.7% when the filling amount is 1.0 wt%. This simple method provides a new strategy for modifying BP and is expected to be applied to the preparation of high performance polymer-based composites. [Display omitted] • An isolation structure with black phosphorus and polystyrene microspheres is achieved. • The electrochemical diazo modification of black phosphorus is the first report. • The heat release rate and smoke production rate of the isolation structure is significantly reduced. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
26. Octopus sucker-inspired hierarchical structure MXene@carbon nanotubes enhancing the mechanical properties and fire safety of thermoplastic polyurethane composites through the interfacial engineering.
- Author
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Jia, Pengfei, Lu, Jingyi, He, Ruofan, Jiang, Guangyong, Jiang, Xin, Wang, Bibo, Song, Lei, and Hu, Yuan
- Subjects
- *
FIRE prevention , *NANOTUBES , *THERMOPLASTIC composites , *HEAT release rates , *MECHANICAL behavior of materials , *OCTOPUSES , *CARBON monoxide - Abstract
[Display omitted] • The octopus sucker-inspired M@CN with hierarchical structure is successfully synthesized. • The Interface engineering between M@CN and TPU matrix is greatly improved. • TPU/M@CN demonstrates superior improvement of TS of 79.5% and EB of 113.5%. • The pHRR and smoke suppression of TPU/M@CN-3 are reduced by 54.1% and 40.4%, respectively. Developing high-performance polymer materials with excellent mechanical properties and fire safety in fires remains a thorny challenge. In this article, hierarchical structure MXene@carbon nanotubes (M@CN) are prepared through electrostatic interactions for enhancing the interfacial engineering of thermoplastic polyurethane (TPU). With biomimetic method, the TPU/M@CN-3 nanocomposites performed octopus sucker-inspired structure during the stretching behavior, making the tensile strength and elongation at break of TPU/M@CN-3 increase 79.5% and 113.5%, respectively. What's more, thanks to the 1D-2D hierarchical structure of M@CN, fire safety of these TPU nanocomposites were extremely reinforced. Compared with the pure TPU, the TPU/M@CN-3 of peak heat release rate (pHRR) and smoke density max (Ds max) reduced by 54.1% and 40.4%. The production rates of carbon monoxide (CO) and carbon dioxide (CO 2) were reduced by 62.7% and 33.0%, respectively. Therefore, this work provides a convenient way to prepare a high-performance TPU with highly mechanical properties and fire safety through enhacing the interfacial engineering. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
27. Photothermal and fire-safe epoxy/black phosphorene composites: Molecular structure analysis of sutured char.
- Author
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Zou, Bin, Qiu, Shuilai, Jia, Pengfei, Jiang, Xin, Song, Lei, and Hu, Yuan
- Subjects
- *
FIREPROOFING agents , *MOLECULAR structure , *HEAT release rates , *CHAR , *COMPOSITE structures , *COMBUSTION - Abstract
[Display omitted] • Photothermal of EP/SL-EBP-CoP is linearly increased (r2 > 0.994). • EP/SL-EBP-CoP 2 separately reduces PHRR, THR and PCOP by 59.88%, 39.26% and 36.41%. • Phosphorus, P-O-P and P-O-C are nodes, units and capture bonds in 3D sutured char. • Rupture molecules of char layer (C n H 2n+2 PO 4 , m / z = 168, 139 and 124) are discovered. To overcome the high flammability of polymers and endow them with photothermal capability, we fabricate the targeted nanofiller black phosphorus (BP) based SL-EBP-CoP for epoxy. Interestingly, the good ability of photothermal for EP/SL-EBP-CoP 2.0 nanocomposite changes with irradiation power can be linearly quantified (r2 > 0.94). Secondly, EP/SL-EBP-CoP 2.0 separately reduces peak heat release rate (HRR), total HRR and peak carbon monoxide (CO) production by 59.88%, 39.26% and 36.41% compared with EP, along with the lowest fire growth index. The significantly reduced hazard of heat and CO is attributed to the combined effects of 2D BP, catalysis of CoP and the structure of sutured char. Finally, the pyrolysis of BP-based flame retardants produces P 4 , P 3 and P 2 with an abundance of 77.10%, 6.75% and 14.70%. Moreover, flame retardant composites are highly dependent on the final char. This work demonstrates that phosphorus and P-O-P (PO x) are nodes and bonding units in the char, PO x bonds to the hydrocarbon fragments through P-O-C bonds. Particularly, pyrolysis molecules of suture and rupture of char (C n H 2n+2 PO 4 , m / z = 168, 139 and 124) are first discovered. This work booms the path and lays the foundations for the photothermal and fire safety of BP nanocomposites. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
28. Revealing and modeling of fire products in gas-phase for epoxy/black phosphorus-based nanocomposites.
- Author
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Zou, Bin, Qiu, Shuilai, Wang, Jingwen, Yang, Wenhao, Liao, Can, Yu, Heng, Li, Xingjun, Qi, Liangyuan, Gui, Zhou, and Hu, Yuan
- Subjects
- *
FIREPROOFING agents , *TITANIUM dioxide , *NANOCOMPOSITE materials , *PRODUCT attributes , *FIRE prevention , *POLYMERIC nanocomposites - Abstract
This work aims at revealing and optimizing the mechanism, to promote the design of phosphorus-based flame retardants (PFRs) for controlling the spread of fire risk caused by the continuous spread of polymers. Herein, we synthesized about 10 nm TiO 2 grown in situ on the surface of BP through a simple hydrothermal procedure to introduce it into epoxy (EP/BP-TiO 2). In the first place, EP/BP-TiO 2 2.0 nanocomposite achieves a reduction of 58.96% and 50.35% in PHRR and THR, respectively. Secondly, the pyrolysis of BP from P n to P 4 , P 3 and P 2 is revealed. As a guide, P 4 is established as a characteristic product of the analytical model for evaluating the effects in the gas phase for BP-based hybrids. Finally, this work clarifies the enhancement path for BP-TiO 2 is optimized for the capturing of OH· and H· radicals by P 4 (PO x). Crucially, this study reveals and controls the mechanism of the BP-based hybrids at the molecular level, which is expected to provide a promising analytical model for broad market PFRs design to address the risks and challenges of casualties and ecology caused by composites fire. [Display omitted] • ∼10 nm TiO 2 grows in situ on the surface of BP nanoflakes. • EP/BP-TiO 2 2.0 reduced PHRR and THR by 58.96% and 50.35%. • BP-TiO 2 optimizes the capture of OH· and H· radicals by P 4 (P 3 and P 2). • BP products can identify and quantify its environmental impact and toxicity. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
29. Ultra-tough, photothermal healing and fire safety polystyrene/hydroxylated black phosphorus-triazine COF composites.
- Author
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Zou, Bin, Qiu, Shuilai, Qian, Ziyan, Li, Wensheng, Chu, Fukai, Xiao, Yuling, Zhou, Yifan, Niu, Haoxin, Song, Lei, and Hu, Yuan
- Subjects
- *
FIREPROOFING agents , *FIRE resistant polymers , *FIRE prevention , *TRIAZINES , *HEAT release rates , *POLYSTYRENE , *HEALING , *ENTHALPY - Abstract
Devoting to coping with safety risk spreading with polymers, this work achieves dramatic synergistic improvements in composite toughness, photothermal healing, and fire safety through a novel targeted modification strategy for black phosphorus (BP). In detail, we herein use the emerging 2D BP as a template for in-situ growth by covalent triazine framework (HBP-CTF). Incorporating gradient increased HBP-CTF (1, 2, 4 wt%) into polystyrene (PS), the elongation at break increased by 61.59%, 74.60% and 62.82% for composites, respectively. This is attributed to the synergistic effects of two components of HBP-CTF as stress conduction unit and interface and dispersion improver, respectively. Furthermore, PS/HBP-CTF composites achieve photothermal healing over 96% in strength and elongation at break induced by outstanding photothermal properties (linearly quantifiable, R2 > 0.997). Noted, PS/HBP-CTF 2.0 and PS/HBP-CTF 4.0 achieve record reductions of 61.77% and 69.85% in peak heat release rate, accompanied by dramatically reduced total heat release. Taking the pyrolysis of HBP-CTF as an index, this work proposes the idea of using P 4 as the key product to monitor and distribute gas phase effects for BP-based flame retardants. The hybridization of CTF to HBP promotes the slow and continuous release of P 4 in the gas phase, revealing the structure and composition of char that cross-linking P and N. This work provides strategies for synergistically overcoming composite brittleness, crack failure, and high flammability, paving the way for practical applications. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
30. Multifunctional fireproof electromagnetic shielding polyurethane films with thermal management performance.
- Author
-
Jia, Pengfei, Zhu, Yulu, Lu, Jingyi, Wang, Bangyu, Song, Lei, Wang, Bibo, and Hu, Yuan
- Subjects
- *
ELECTROMAGNETIC shielding , *PERFORMANCE management , *FIREPROOFING , *ELECTRIC conductivity , *FIRE prevention , *THERMAL conductivity , *MICROENCAPSULATION - Abstract
• The MAPP is prepared by the conductive MXene wrapped on the surface of APP. • The conductive structure of PU film is composed by the 1-D GF and 0-D MAPP. • PU/GF/MAPP film shows the EMI SE as high as 58.9 dB with thickness of 1.0 mm. • PU film presents outstanding mechanical property, joule heating and thermal management performance. • PU/GF/MAPP film reveals excellent flame retardancy and smoke suppression properties. A multifunctional polyurethane film (PU) with superior electromagnetic shielding performance, joule heating performance, thermal conductivity and flame retardancy has been carefully designed. The ammonium polyphosphate (APP) wrapped with conductive MXene (MAPP) is prepared by microencapsulation technology and added in PU solution for enhancing the electric conductivity of PU/graphite fiber (GF) film. The three-dimensional (3D) conductive network composed of GF and MAPP promotes electron transmission efficiency and electromagnetic (EM) wave dissipation through multiple absorbtion and reflection. Compared with the PU/GF film, the electric conductivity and thermal conductivity of PU/GF/MAPP film enhanced by 57.7% and 59.3%, respectively. What's more, the PU composite film shows excellent mechanical properties, joule heating performance and high fire safety performance. Therefore, the prepared multifunctional PU film demonstrates excellent performance, and has broad application prospects in EMI shielding and thermal management of advanced microelectronic systems. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
31. Innovative design of environmentally friendly silicon-based polyphosphazene-functionalized hydroxyapatite nanowires: An efficient enhancement strategy for the fire safety and mechanical properties of unsaturated polyester.
- Author
-
Zhou, Yifan, Qiu, Shuilai, Ding, Longlong, Chu, Fukai, Liu, Wei, Yang, Wenhao, Hu, Weizhao, and Hu, Yuan
- Subjects
- *
UNSATURATED polyesters , *FIRE prevention , *HYDROXYAPATITE , *NANOWIRES , *HEAT release rates , *FIREPROOFING agents , *POLYESTER fibers , *POLYESTERS - Abstract
[Display omitted] • Environmentally friendly new flame retardant f-HAPNW was successfully prepared. • f-HAPNW achieved high filler efficiency in reducing THR and TSP of UPR nanocomposites. • UPR/f-HAPNW 0.5 achieved an 61.2 % increase in impact strength. • Novel flame retardancy and mechanical reinforcement mechanism about f-HAPNW. Non-toxic, low-smoke, high-efficiency and environmentally friendly flame retardants have become a hot issue at present. Here, polyphosphazene crosslinked by hexachlorocyclotriphosphazene (HCCP), 3-aminopropyltriethoxysilane (APTES), and dopamine (DA) was used to modify hydroxyapatite nanowires (HAPNW), obtaining a new environmentally friendly nanohybrids (f-HAPNW). Immediately afterwards, f-HAPNW was incorporated in unsaturated polyester (UPR) matrix in the presence of a nanowire structure with a high aspect ratio, accompanied by excellent interfacial compatibility. The incorporation of a small amount of f-HAPNW achieved an overall improvement in the fire safety and mechanical properties of UPR nanocomposites, including 23% decrease in total heat release rate (THR), 25.7% and 29.5% reduction in total smoke production (TSP) and the peak of CO production rate (PCOP) when the content was 2.0 wt%; 80.1% and 11.9% simultaneous increase in tensile strength and fracture elongation, and 61.2% increase in impact strength when the content was 0.5 wt%. Compared with similar previous research, the introduction of bio-based materials and environmentally friendly flame retardants in the design achieved significant flame-retardant filler efficiency, while considering the issues of reducing smoke release and environmental pollution. In general, this work innovatively prepared an environmentally-friendly hierarchical f-HAPNW structure, and achieved a comprehensive improvement in the performance of UPR nanocomposites, providing a reference idea for the design of high-performance UPR nanocomposites. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
32. Fabrication of fire safe rigid polyurethane foam with reduced release of CO and NOx and excellent physical properties by combining phosphine oxide-containing hyperbranched polyol and expandable graphite.
- Author
-
Ma, Chao, Qiu, Shuilai, Xiao, Yuling, Zhang, Kang, Zheng, Yapeng, Xing, Weiyi, and Hu, Yuan
- Subjects
- *
URETHANE foam , *HEAT release rates , *ENTHALPY , *FIRE resistant polymers , *PHYSICAL mobility , *FOAM , *COMBUSTION gases , *PHOSPHINE - Abstract
[Display omitted] • A novel phosphine oxide-containing hyperbranched polyol was synthesized. • RPUF containing POCHP and EG exhibit excellent fire safety and physical properties. • The production of CO and NO x during combustion of RPUF are significantly decreased by combination of POCHP and EG. In this work, a novel phosphine oxide-containing hyperbranched polyol (POCHP) was synthesized. Then POCHP and/or expandable graphite (EG) were incorporated into rigid polyurethane foam (RPUF). EG increases foam density and deteriorates compressive strength and thermal conductivity, but POCHP has opposite effects. A 12.8% improvement of compressive strength and slightly decreased density and thermal conductivity are achieved by ERPUF50 containing POCHP and EG. And it reaches a limited oxygen index of 30.0% and UL-94 V-0 rating with immediate self-extinguishing behavior after removing flame. The peak heat release rate, total heat release and total smoke production of ERPUF50 are reduced by 71.1%, 52.2% and 71.1% respectively via bi-phase flame retardant mechanisms. Interesting phenomena were observed that POCHP promotes the intumescence of EG after combustion. The results of combustion gas analysis reveal that single POCHP or EG reduces the production of CO but increases the generation of NO x. ERPUF50 exhibits a 52% decrement of CO and an unexpected 40% diminishment of NO x. ERPUF50 with excellent comprehensive properties can not only be used as fire safe thermal insulation material with high physical performances, but also significantly reduce the release of contaminative smoke, CO and NO x in fires and waste RPUF disposal by combustion. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
33. Bifunctional linear polyphosphazene decorated by allyl groups: Synthesis and application as efficient flame-retardant and toughening agent of bismaleimide.
- Author
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Zhou, Xia, Qiu, Shuilai, He, Lingxin, Cai, Wei, Chu, Fukai, Zhu, Yulu, Jiang, Xin, Song, Lei, and Hu, Yuan
- Subjects
- *
HEAT release rates , *FIREPROOFING agents , *REACTIVE oxygen species , *ALLYL group , *FIRE prevention - Abstract
As known, the poor toughness and low fire safety of bismaleimide resin (BMI) has become a problem which restricts its further application in advanced high-performance field. Therefore, a novel allyl-functionalized linear polyphosphazene (PMAP) was designed and synthesized. With inclusion of 3wt% PMAP, the peak heat release rate (PHRR) and total smoke production (TSP) of BMI/PMAP-3 are reduced by 51.3% and 17.8%, respectively. And the residual char of BMI/PMAP increases significantly as well. Furthermore, the flame-retardant mechanism of BMI/PMAP is proposed. In condensed phase, PMAP can participate in the formation of residual char of BMI/PMAP and the char layer is with an excellent physical barrier effect by the existence of phosphorus oxygen and phosphorus nitrogen cross-linking substances. In gas phase, phosphorous oxygen free radical is also generated from PMAP, which can capture gas-phase chain free radicals and inhibit gas-phase combustion. Moreover, the impact strength of BMI/PMAP-3 increases by 85.3%, which indicates that the toughness of BMI/PMAP is effectively enhanced. The toughening mechanism of PMAP on BMI can be assigned to elastomer toughening. Therefore, with modification of PMAP, BMI/PMAP is indeed of better comprehensive performance, which is in line with expectation and provides inspiration for the simultaneous flame-retardant and toughening modification of BMI. [Display omitted] • Innovation: bifunctional allyl functionalized linear polyphosphazene was firstly synthesized. • High-efficiency: the PHRR and impact strength of BMI/PMAP-3 is reduced by 51.3% and increased by 85.3%. • Mechanism: the flame retardant and toughening mechanism is proposed. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
34. MOF-derived strategy to obtain CuCoOx functionalized HO-BN: A novel design to enhance the toughness, fire safety and heat resistance of bismaleimide resin.
- Author
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Zhou, Yifan, Chu, Fukai, Yang, Wenhao, Qiu, Shuilai, and Hu, Yuan
- Subjects
- *
FIRE prevention , *HEAT release rates , *BORON nitride , *GLASS transition temperature , *FIRE resistant polymers , *ENTHALPY , *CARBON monoxide - Abstract
• Hydrophobic hierarchical OH-BN@CuCoOx was innovatively prepared by the MOF-derived strategy. • OH-BN@CuCoOx achieved high filler efficiency in reducing THR and TSP of BMI. • BMI/OH-BN@CuCoOx 0.5 achieved an 80 % increase in impact strength. • BMI/OH-BN@CuCoOx 0.5 achieved a 49 °C increase in Tg. In this work, the MOF-derived strategy was used to generate copper-cobalt metal oxide (CuCoOx) in situ on the surface of hydroxylated boron nitride (HO-BN), and a new type of nano-hybrid (HO-BN@CuCoOx) was obtained. Then, HO-BN@CuCoOx was dispersed in the bismaleimide resin (BMI) matrix in the form of a layered structure, forming a strong interface interaction. The results of the cone calorimeter test exhibited that the fire hazard and toxic smoke release of BMI nanocomposites containing 2 wt% HO-BN@CuCoOx were effectively suppressed, such as a 37.2% reduction in total heat release rate (THR), a 38.5% reduction at peak heat release rate (PHRR), 24.3% decrease in total smoke production (TSP) and 62.2% decrease in peaks of carbon monoxide (CO) production rate. Compared with previous studies, higher filling efficiency was achieved. In addition, BMI/HO-BN@CuCoOx 0.5 achieved an 80% increase in impact strength, revealing excellent toughness. In particular, the glass transition temperature (Tg) of BMI/HO-BN@CuCoOx 0.5 reached 330 °C, an increase of 49 °C compared to the pure sample, which increased the potential for application in extreme environments. Therefore, the developed new BMI/HO-BN@CuCoOx nanocomposites expanded the application potential of BMI in the high-end field. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
35. Cleaner production to a multifunctional polyurethane sponge with high fire safety and low toxicity release.
- Author
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Lu, Jingyi, Liao, Can, Cheng, Liang, Jia, Pengfei, Yin, Zhenting, Song, Lei, Wang, Bibo, and Hu, Yuan
- Subjects
- *
SPONGE (Material) , *FIRE prevention , *GREEN business , *HEAT release rates , *FIREPROOFING agents , *CONDUCTING polymer composites - Abstract
Conductive polymer composites have been caught increasing attentions in electromagnetic interference (EMI) shielding field. Due to the flammability of polymer and long-term high power working status, fire incidents on environment and human health must be taken into consideration during the preparation of the polymer materials. Thus, developing an EM waves-clean material with exceptional fire safety and smoke suppression capacity is the vital issue. In this article, a facile and eco-friendly approach to fabricate flame retardant polyurethane (PU) sponge was carried out by layer-by-layer (LBL) self-assembly with octaammonium-polyhedral oligomeric silsesquioxane (OAPOSS) and titanium carbide (Ti 3 C 2 T x) nanosheets. With the help of silicane and the barrier effect from Ti 3 C 2 T x , the peak heat release rate (pHRR) and total heat release (THR) decreased by 50%. Thanks to the exceeding catalytic capacity of Ti 3 C 2 T x nanoflakes, the production of harmful smokes or gases such as carbon oxide (CO) and carbon dioxide (CO 2) were sharply reduced with 71% and 27%, respectively. Furthermore, the flame retardant PU sponge obtained electromagnetic interference (EMI) shielding capacity after dip-coating procedure in MXene dispersion owing to the excellent electrical conductivity of Ti 3 C 2 T x nanosheets. The EMI shielding effectiveness (EMI SE) accomplished 32.57 dB and still remained 27.63 dB after 300 times compression. Therefore, this work could provide a promising way to accomplish flame retardant PU sponge with superior smoke suppression capacity, which could be used in cleaner production of modern electronics and EMI shielding materials. [Display omitted] • The facile cleaner approach to obtain multifunctional polyurethane (PU) sponge. • OAPOSS@MXene nanocoating was constructed on PU sponge via a clean layer-by-layer method. • The peak heat release rate and CO production was decreased by >50% and 71%, respectively. • Electromagnetic interference shielding capability remained >85% after 300 times compression. • Toxic fire effluents release-cleaner, electromagnetic waves-cleaner production of PU sponge were achieved. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
36. Preparation of soybean root-like CNTs/bimetallic oxides hybrid to enhance fire safety and mechanical performance of thermoplastic polyurethane.
- Author
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Hou, Yanbei, Liao, Can, Qiu, Shuilai, Xu, Zhoumei, Mu, Xiaowei, Gui, Zhou, Song, Lei, Hu, Yuan, and Hu, Weizhao
- Subjects
- *
FIRE prevention , *SOYBEAN , *POLYURETHANES , *ROOT-tubercles , *HEAT radiation & absorption , *EXHAUST gas recirculation - Abstract
[Display omitted] • Soybean root-like CNTs/BMO hybrid was prepared with ZIFs as precursor. • Well-dispersed hybrid decreased the release of heat, smoke and toxic gases of TPU. • The toughness and strength of TPU were obviously improved by CNTs/BMO hybrid. • A non-organic strategy was demonstrated to prepare high-performance TPU. The three main fatal factors considered when Thermoplastic polyurethane (TPU) products catch fire are massive heat radiation, suffocation by smoke inhalation, and poisoning by toxic gases (CO and HCN). In this study, to weaken these adverse impacts, soybean root-like zeolitic imidazolate frameworks (ZIFs)-derived carbon nanotubes/bimetallic oxides (CNTs/BMO) hybrids are designed and prepared. In addition, we studied its performance in improving the fire safety of TPU. The in-situ growth of ZIFs on the surface can suppress the entanglement of CNTs (main roots), enhancing a uniform dispersion in the hybrid. Porous BMO and ultrathin N-doped CNTs (N-CNTs) functioned as conversion stations for organic and inorganic, similar to the root nodules and root hairs, respectively, resulting in the increased generation of char residues and suppressed emissions of smoke and toxic gases. Compared with neat TPU, there are 32.11%, 27.91%, and 41.91% reductions in peak heat-release rate, total smoke production, and total CO production, respectively, with 1 wt% of well-dispersed CNTs/BMO hybrids. In addition, the soybean root-like hybrids also have enhanced the mechanical performance of composites. On the basis of the satisfactory mechanical strength of neat TPU, the tensile strength and elongation (at break) of the soybean root-like hybrids are further increased by 70.61% and 16.49%, respectively. This work provides a feasible method to construct a well-dispersed inorganic hybrid with complex structure and excellent performance, which will deliver a new perspective for the development of multifunctional polymer composites. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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37. Designing advanced 0D-2D hierarchical structure for Epoxy resin to accomplish exceeding thermal management and safety.
- Author
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Lu, Jingyi, Wang, Bibo, Jia, Pengfei, Cheng, Wenhua, Liao, Can, Xu, Zhoumei, Cheng, Liang, and Hu, Yuan
- Subjects
- *
EPOXY resins , *HEAT release rates , *ENTHALPY , *FIREPROOFING agents , *PACKAGING materials , *CATALYSIS - Abstract
[Display omitted] • 0D-2D hierarchical nanostructure was prepared via ZHS in-situ growing on Ti 3 C 2 T x. • EP-ZHS@M composites show up superior improvement of thermal conductivity of 328%. • EP-2.0 ZHS@M performed low pHRR of 54.91% and outstanding smoke suppression. • ZHS@M cut off the thermal disaster chain for safer package materials. Epoxy resin (EP) is widely used in the package of modern electronic products for thermal management, but the extremely flammability and toxicity release have restricted its further application. In this article, zinc hydroxystannate (ZHS) nanocubes were in-situ fabricated on the surface of titanium carbide (Ti 3 C 2 T x) MXene nanosheets (ZHS@M) for improving the thermal management capacity of EP. Due to the phonon thermal conductance from ZHS and electron-hole thermal conductance of Ti 3 C 2 T x , the thermal conductivity was improved by 328% compared with the neat EP, which was benefit to dissipate heat for reducing the possibility of thermal disaster chain happening. Furthermore, owing to the 0D-2D hierarchical structure of ZHS@M, the fire safety and smoke suppression of these EP composites were highly strengthened. The peak heat release rate (pHRR) and total heat release (THR) decreased by 54.91% and 58.74%, respectively. Moreover, hazardous gases of EP during the combustion were also efficiently reduced, and the generation of carbon oxide (CO) and carbon dioxide (CO 2) were decreased by 44.44% and 39.46% when the additive of ZHS@M was only 2 wt%. As a result, ternary catalytic effect and labyrinth structure improved the safety of EP in the thermal runaway incidents. Besides, EP-2.0 ZHS@M exhibited excellent tensile robustness (64.71 MPa) and modulus (2.39 GPa), which regarded as a reliable supporting material for electronics in thermal management field. Hence, this hierarchical EP-ZHS@M composites provided the help of cleaning the thermal accumulation and increasing fire safety while facing thermal runaway, which was significant to destroy the formation of thermal disaster chain and further applications of the modern electrons and devices. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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38. Construction of hierarchical Ti3C2TX@PHbP-PHC architecture with enhanced free-radical quenching capability: Effective reinforcement and fire safety performance in bismaleimide resin.
- Author
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Zhou, Yifan, Qiu, Shuilai, Guo, Wenwen, Chu, Fukai, Zhou, Xia, Chen, Weijian, Wang, Jingwen, Zhang, Kang, Cheng, Liang, and Hu, Yuan
- Subjects
- *
FIRE prevention , *FIREPROOFING agents , *ENTHALPY , *CONDENSED matter , *IMPACT strength , *HEAT release rates - Abstract
• Hierarchical Ti 3 C 2 T X @PHbP-PHC architecture was innovatively synthesized. • Ti 3 C 2 T X @PHbP-PHC exhibited significant decrease in PHRR, THR and TSP. • BMI/Ti 3 C 2 T X @PHbP-PHC 0.5 achieved a significant increase in impact strength. • The synergistic mechanical reinforcement and flame-retardant mechanism among Ti 3 C 2 T X , PHbP and PHC was innovatively revealed. The effect of hindered amine light stabilizer on free radical quenching can be combined with the cross-linked polyphosphazene containing P N structure to improve the flame retardant efficiency of titanium carbide (Ti 3 C 2 T X) in both gas phase and condensed phase. Here, a hindered amine and polyphosphazene modified Ti 3 C 2 T X (Ti 3 C 2 T X @PHbP-PHC) was obtained. With the loading of Ti 3 C 2 T X @PHbP-PHC in the bismaleimide resin (BMI) increased to 2 wt%, an 43% reduction was achieved in the peak heat release rate (PHRR), and a 47% reduction in the total heat release rate (THR). Meanwhile, the total gaseous products and total smoke production (TSP) exhibited a similar decreasing trend. Furthermore, 0.5 wt% BMI system exhibited the highest storage modulus (2629 MPa) and impact strength (13.7 MPa), which were 21% and 76% higher than pure BMI, respectively. Therefore, the developed functionalized Ti 3 C 2 T X can be effectively used in BMI matrix, thereby providing reliable source material for the design of high-performance BMI resins that meet various application scenarios. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
39. Synthesis of star-shaped allyl phosphazene small molecules for enhancing fire safety and toughness of high performance BMI resin.
- Author
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Zhou, Xia, Qiu, Shuilai, He, Linxin, Wang, Xin, Zhu, Yulu, Chu, Fukai, Wang, Bibo, Song, Lei, and Hu, Yuan
- Subjects
- *
FIRE prevention , *SMALL molecules , *NUCLEOPHILIC substitution reactions , *FIREPROOFING agents , *IMPACT strength , *ALLYL alcohol - Abstract
[Display omitted] • Innovation: Star-shaped Allyl Functionalized phosphazenes are synthesized. • High-efficiency: PHRR and TSP of BMI/HMACP-5 reduced by 46.1% and 53.1%. • The best impact strength of BMI/HECP-5 increased by 195%. • Mechanism: the flame retardant and toughening mechanism were proposed. As a typical aerospace advanced resin-based material, the high brittleness and poor fire safety performance of bismaleimide resin (BMI) has been the key factor restricting its further development. Therefore, two star-shaped allyl functionalized phosphazene small molecules (HMACP, HECP) were designed and synthesized utilizing the nucleophilic substitution reaction between hexachlorocyclotriphosphazene (HCCP) and allyl alcohol/eugenol for enhancing the flame retardant and toughness of BMI. It's observed with the inclusion of HMACP and HECP, the heat and smoke release behavior of BMI/HMACP and BMI/HECP are effectively suppressed. The fire risk of BMI samples are evaluated by fire growth index (FGI) and fire performance index (FPI) calculated by cone calorimeter results. And with the addition of 5 wt% HMACP and HECP, the FGI of BMI/HMACP-5 and BMI/HECP-5 possess the lowest values of 1.51 and 1.04 kW/(m2 s), respectively. Besides, the FPI of BMI/HMACP-5 and BMI/HECP-5 are highest and the values are 0.36 and 0.37 (m2 s)/kW, respectively, which indicates that the fire safety performance of BMI/HMACP-5 and BMI/HECP-5 are significant improved. Meanwhile the impact strength of BMI/HMACP-5 and BMI/HECP-5 are increased by 117% and 195%, respectively, which means the toughness of BMI resin with the modification of HMACP and HECP is improved. The flame retardant mechanisms of BMI/HMACP and BMI/HECP are investigated systematically. Comparative analysis of the similarities and differences between BMI/HMACP and BMI/HECP are also conducted. Therefore, it can be drawn that the designed HMACP or HECP can effectively improve the toughness and fire safety performance of BMI. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
40. A novel coating of hyperbranched poly(urethane-phosphine oxide) for poly(methyl methacrylate) with high fire safety, excellent adhesion and transparency.
- Author
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Zhang, Kang, Ma, Chao, Zheng, Yapeng, Zhou, Feng, Xiao, Yuling, Xing, Weiyi, and Hu, Yuan
- Subjects
- *
PHOSPHINE oxides , *METHYL methacrylate , *SURFACE coatings , *FIRE prevention , *HEAT release rates , *FIREPROOFING agents - Abstract
In order to enhance the fire resistance of poly(methyl methacrylate) (PMMA), a new transparent flame-retardant coating was prepared by coating hyperbranched poly(urethane-phosphine oxide) (HPUPO) onto PMMA surface, which was synthesized from 4,4′-diphenylmethane diisocyanate (MDI) and trihydroxymethylphosphine oxide (THPO). The ratio of MDI to THPO was changed to prepare HPUPO with different structures. The HPUPO coatings show a strong adhesion of 5B grade to PMMA and all coated PMMA have a high transparency as pure PMMA. In cone calorimetry test, peak heat release rate (PHRR) of all HPUPO coated PMMA decrease very obviously. The PHRR and total heat release (THR) values of PMMA-0.8 (HPUPO coated PMMA with the ratio of MDI to THPO 1: 0.8) are reduced by 83.6% and 33.0% compared to those of pure PMMA. For PMMA-1.1 and PMMA-1.25, the heat, smoke and toxic gas release are all decreased effectively, which indicates improvement of fire safety of PMMA. The PHRR, THR, total smoke production (TSP) and CO yield (COY) of PMMA-1.1 are decrease by 83.3%, 11.0%, 27.6% and 34.8%, respectively. In the back temperature test, PMMA-0.95 and PMMA-1.1 have the lowest back temperature rise rates in HPUPO coated PMMA, and the back temperature are about 200 °C under the continuous burning of the alcohol lamp for 800 s. In summary, PMMA-1.1 shows excellent transparency, adhesion and fire safety. HPUPO coated PMMA is a promising fire safe PMMA material for practical application and HPUPO can be used as transparent flame retardant coating with tailorable properties. [Display omitted] • A transparent flame retardant coating for PMMAwas prepared with hyperbranched poly(urethane-phosphine oxide). • The HPUPO coatings show a strong adhesion and high transparency. • The HPUPO coatings can effectively improve the fire safety of PMMA. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
41. Random nano-structuring of PVA/MXene membranes for outstanding flammability resistance and electromagnetic interference shielding performances.
- Author
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Wang, Wei, Yuen, Anthony Chun Yin, Long, Hu, Yang, Wei, Li, Ao, Song, Lei, Hu, Yuan, and Yeoh, Guan Heng
- Subjects
- *
ELECTROMAGNETIC interference , *ELECTROMAGNETIC shielding , *POLYMER blends , *HEAT release rates , *POLYMERIC membranes , *CONDUCTING polymer composites , *ELECTRIC conductivity - Abstract
Nowadays, highly flexible, ultrathin, and conductive polymer composites are exceptionally desirable for electromagnetic interference shielding (EMI) applications due to their unique mechanical strength and electrical and flame-resistant properties. While the traditional nanocomposites blending remains the mainstream method to fabricate polymer/inorganic composites, it results in poor electrical conductivity caused by the discontinuous connection of conductive network as well as the unsatisfactory mechanical strength limiting the further practical applications. Herein, we introduce a facile and practical methodology involving the fabrication of self-interlocked poly (vinyl alcohol) (PVA) and conductive Ti 3 C 2 T x MXene networks, then combining them to construct a nanostructure-engineered PVA/MXene membrane. This membrane exhibits superior mechanical strength, in which the tensile strength is about three times higher than the control PVA. Additionally, the membrane demonstrates outstanding fire-resistant performances with an 80% reduction of peak heat release rate than pure PVA. More importantly, this unique membrane with random conductive networks possesses an outstanding EMI shielding efficiency near 41 dB much greater than traditional composite, which meets the requirement of high-efficiency EMI shielding applications. This article displays a novel strategy to fabricate a nanostructured polymer membrane with outstanding fire resistance, electrical conductivity, and mechanical strength, targeted and designed for high-efficiency EMI shielding applications. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
42. Surface modification of multi-scale cuprous oxide with tunable catalytic activity towards toxic fumes and smoke suppression of rigid polyurethane foam.
- Author
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Yuan, Yao, Wang, Wei, Xiao, Yi, Chun Yin Yuen, Anthony, Mao, Long, Pan, Haifeng, Yu, Bin, and Hu, Yuan
- Subjects
- *
FIRE resistant polymers , *CUPROUS oxide , *URETHANE foam , *HEAT release rates , *CATALYTIC activity , *CARBON monoxide , *SMOKE - Abstract
[Display omitted] • Nano-, submicron- and micron-sized Cu 2 O crystals were synthesized and confirmed. • The surface modification of Cu 2 O with PAPI improved the efficiency and dispersion. • Nano-sized Cu 2 O with the high surface area conduced to the complete combustion of RPUF. • The flame retardance and smoke toxicity suppression of Cu 2 O was explored. The development of flame retardant rigid polyurethane foam (RPUF) composites with low smoke toxicity emission, as well as excellent mechanical properties remains a huge challenge. Herein, a facile wet chemical approach was proposed for the preparation of cuprous oxide (Cu 2 O) crystals with different sizes, i.e. approximately 5 nm, 100 nm and 1 μm in lateral size, which were confirmed by X-ray diffraction and transmission electron microscopy. The effect of Cu 2 O crystals on the combustion behavior of RPUF was evaluated by cone calorimetry and steady state tube furnace tests. Significant reduction in peak carbon monoxide (CO) production rate (by 41.2%, 67.6% and 27.9%) and total smoke production (21.6%, 16.1% and 12.2%) were realized by the incorporation of 2 wt% Cu 2 O into the RPUF matrix in addition to a slight reduction in peak heat release rate. Notably, nano-sized Cu 2 O with high specific surface area is beneficial for the complete combustion of RPUF and the conversion of CO to carbon dioxide (CO 2), involving the reduction of Cu2+-Cu+-Cu0 by degraded gases and the oxidation of Cu0-Cu+-Cu2+ by oxygen. This work demonstrated that submicron-sized Cu 2 O is an effective smoke and toxic gases suppressant for RPUF, which is expected to find practical applications in polymeric materials. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
43. Barrier function of graphene for suppressing the smoke toxicity of polymer/black phosphorous nanocomposites with mechanism change.
- Author
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Cai, Wei, Li, Zhaoxin, Mu, Xiaowei, He, Lingxin, Zhou, Xia, Guo, Wenwen, Song, Lei, and Hu, Yuan
- Subjects
- *
NANOCOMPOSITE materials , *GRAPHENE , *POLYMERS , *CARBON dioxide , *POLYMERIC nanocomposites - Abstract
Recently, black phosphorous (BP) nanosheets as an emerging nanomaterial have presented significant fire safety improvement in polymer nanocomposites. However, as elemental phosphorus, fire safety improvement effect of BP nanosheets on polymer composites builds on the conversion of gaseous pyrolysis products into smoke particles, which inevitably promotes the formation and release of smoke particles. From the perspective of overall fire safety improvement, it is vital to simultaneously suppress the heat release and smoke production of polymer/BP composites. Herein, melamine-mediated graphene/black phosphorous nanohybrids (GNS/MA/BP) were fabricated through electrostatic-driving self-assembly process and introduced into polyether thermoplastic polyurethane (TPU). During combustion, the barrier function provided by thermally stable layered structure of graphene (GNS) enables more pyrolysis products of BP nanosheets to be kept within condensed phase and react with polymer matrix. Compared to pure TPU, the incorporated hierarchical nanostructure (GNS/MA/BP-2) decreases PHRR, THR, and total CO 2 release of TPU composite by 54.7%, 23.5%, and 32.5%, respectively. Beside, in contrast to TPU-BP composite, the release rate of toxic smoke and CO gas of TPU-GNS/MA/BP-2 composite are reduced by 46.7% and 49.4%. With barrier function of graphene, the heat and smoke release behavior of polymer/BP nanocomposites is effectively suppressed. ga1 • GNS-MA-BP nanohybrids were obtained by electrostatic self-assembly process. • The heat, CO, and smoke particles were simultaneously suppressed. • Adding GNS decreases smoke release of polymer/BP nanocomposite. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
44. Designing 3D ternary-structure based on SnO2 nanoparticles anchored hollow polypyrrole microspheres interconnected with N, S co-doped graphene towards high-performance polymer composite.
- Author
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Wang, Junling, Ma, Chao, Mu, Xiaowei, Zhou, Xia, He, Lingxin, Xiao, Yuling, Song, Lei, and Hu, Yuan
- Subjects
- *
HEAT release rates , *NANOPARTICLES , *FIREPROOFING agents , *MICROSPHERES , *POLYPYRROLE , *EPOXY resins , *POLYMERIC composites - Abstract
The designing of 3D ternary-structure based on SnO 2 nanoparticles anchored hollow polypyrrole microspheres interconnected with N, S co-doped grapheme (NSG-P-SnO 2). • A 3D ternary-structure of NSG-P-SnO 2 is rationally designed. • Remarkable enhancement in polymer fire safety is achieved by adding NSG-P-SnO 2. • The flame retardancy comparison with reported work affirms the superiority of NSG-P-SnO 2. • Obviously improved mechanical performance is also observed. Inherent nature of serious fire hazard including considerable heat and toxicants releases, have definitely compromised the extensive usage of epoxy resin (EP). In this investigation, a three-dimensional (3D) ternary-structure based on SnO 2 nanoparticles anchored hollow polypyrrole microspheres interconnected with N, S co-doped graphene (NSG-P-SnO 2) is rationally designed, and further incorporated into EP matrix. The markedly suppressed fire hazard is achieved after its incorporation. By adding 3.0 wt% NSG-P-SnO 2 , the reductions on peak heat release rate and total heat release values are 42.4 and 47.8%, separately, reflecting the impeded heat generation. Meanwhile, the peak smoke production rate and total smoke production values are obviously reduced by 27.0 and 40.2%, manifesting the attenuated fire toxicity. The flame retardancy comparison with reported work demonstrates the superiority of NSG-P-SnO 2. Notably, the enhanced mechanical performance is also observed. By using 1.0 wt% NSG-P-SnO 2 , the storage modulus is remarkably elevated by 29.1%. Thus, it is concluded that, using this 3D ternary-structure can endow polymer with high fire safety and mechanical capability, synchronously. This work may provide effective inspiration towards developing multicomponent integrated architecture, optimizing their prospects in polymer-matrix composite as well as other fields. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
45. Construction of porous g-C3N4@PPZ tubes for high performance BMI resin with enhanced fire safety and toughness.
- Author
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Zhou, Xia, Qiu, Shuilai, Liu, Jiajia, Zhou, Mutian, Cai, Wei, Wang, Junling, Chu, Fukai, Xing, Weiyi, Song, Lei, and Hu, Yuan
- Subjects
- *
FIRE prevention , *HEAT release rates , *FIREPROOFING agents , *ENTHALPY , *IMPACT strength , *TUBES - Abstract
• Innovation: novel g-C 3 N 4 @PPZ to promote flame retardant and toughness of BMI. • High-efficiency: PHRR and TSPR of BMI/g-C 3 N 4 @PPZ2.0 reduced by 52.1%, 53.8%. • The best impact strength of BMI/g-C 3 N 4 @PPZ increased by 184.0%. • Mechanism: the flame retardant and toughening mechanism was proposed. It's acknowledged that the inferior toughness of bismaleimide resin (BMI) is the crucial problem hindering its development and application especially in aerospace, mechanical and electronic fields. While the poor fire safety of toughened BMI is another problem urgently needed to be resolved. Therefore a novel g-C 3 N 4 @PPZ hierarchical architecture constituted of porous g-C 3 N 4 tubes modified by polyphosphazene was designed and fabricated to improve the fire safety and mechanical properties of BMI in this work. Especially compared to pure BMI, the peak heat release rate (PHRR) and peak smoke production rate (PSPR) of BMI with an incorporation of 2 wt% g-C 3 N 4 @PPZ (BMI/g-C 3 N 4 @PPZ2.0) are at 246.3 kW/m2 and 0.12 m2/s accompanying with 52.1% and 53.8% reduction respectively. The total heat release (THR) and total smoke production (TSP) of BMI/g-C 3 N 4 @PPZ2.0 are endowed with reductions of 29.4% and 42.9% as well, which demonstrates that the fire safety including heat and smoke hazards of BMI/g-C 3 N 4 @PPZ2.0 is significantly improved. With regard to the mechanical performance of BMI composites, the impact strength of BMI/g-C 3 N 4 @PPZ1.5 is 18.89 kJ/m2 which increases by 184.0% in comparison with that of pure BMI resin (6.65 kJ/m2). And it's found that the impact strength of BMI/g-C 3 N 4 @PPZ are still higher than pure BMI in hot-humid environment, which signifies that the BMI/g-C 3 N 4 @PPZ would be preferred in the industrial applications. Meantime the possible flame retardant and toughening mechanism of g-C 3 N 4 @PPZ in BMI is detailed investigated and proposed as well. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
46. Electrochemical exfoliation and functionalization of black phosphorene to enhance mechanical properties and flame retardancy of waterborne polyurethane.
- Author
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He, Lingxin, Zhou, Xia, Cai, Wei, Xiao, Yuling, Chu, Fukai, Mu, Xiaowei, Fu, Xianling, Hu, Yuan, and Song, Lei
- Subjects
- *
FIRE resistant polymers , *POLYURETHANES , *POLYMERIC nanocomposites , *ENTHALPY , *CONDENSED matter , *FLAME , *HEAT release rates - Abstract
Similar to graphene, few-layer black phosphorus possesses many excellent properties such as good thermal stability, mechanical properties and unique characteristic dimension effects, which is considered as promising nanoadditives. But the low yield and inferior interfacial adhesion with polymer matrix are unavoidable obstruction to fabricate high performance nanocomposites. Herein, we report a facile and environmentally friendly approach to simultaneously exfoliate and modify black phosphorus (BP) by electrochemical cathodic exfoliation, where BP crystal acted as the cathode and ethylene imine polymer (PEI) acted as electrolyte and modifier. The positively charged PEI would uniformly anchor on the surface of the newly peeled-off BP nanosheets through electrostatic attraction effect, resulting in preventing the agglomeration of BP nanosheets and improve the compatibility between BP and waterborne polyurethane (WPU) matrix. Significantly, with the addition of 2.0 wt% PEI modified BP in WPU matrix, the fire safety of WPU composites was enhanced. The peak heat-release rate, total heat release, total smoke production and total CO yield are decreased by 34.3%, 21.2%, 22.3% and 50.2% compared to pure WPU, respectively. Also, the tensile strength of WPU composites was increased by 71% (from 21.9 to 31.0 MPa) at the cost of the breaking elongation slightly decreased by 5.6%. This work provides the possibility for the scalable preparation and a real application of BP in polymer nanocomposites. Image 1 • A facile and environmental route to simultaneously exfoliate and modify BP. • BP-PEI had good flame-retardant contributions in both gaseous and condensed phase. • Functionalized BP enhanced flame-retardant properties of WPU composite. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
47. Building of hierarchical structure of functionalized montmorillonite anchored with ZnO: Toward fabricating high-performance polyethylene composite.
- Author
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Wang, Junling, Wang, Bibo, Ma, Chao, Xiao, Yuling, Guo, Wenwen, Cai, Wei, Song, Lei, Wang, Xin, and Hu, Yuan
- Subjects
- *
ULTRAHIGH molecular weight polyethylene , *HEAT release rates , *ENTHALPY , *FIRE prevention , *MONTMORILLONITE , *COMPOSITE structures - Abstract
As is well known, polyethylene (PE) is flammable with the release of abundant heat, confirming its low fire safety. Consequently, the extended application of PE is restrained. In this work, we propose the facile preparation of multi-component hybrid (functionalized montmorillonite anchored with ZnO, defined as FMZH) and its promising utilization in PE. With the aid of functionalized compound, the obtained hybrid shows good dispersion state, as well as strong interfacial interaction with polymer matrix. By incorporating FMZH fillers, the marked reductions in peak heat release rate (PHRR) and total heat release (THR) can be obtained, corroborating the enhanced fire safety. Specifically, with the addition of 5.0 wt% 1-2FMZH and 1-4FMZH, the PHRR values are reduced to 567 and 667 kW/m2, respectively, corresponding to 54.7 and 46.8% decrease. Also, the suppressing effect on the release of decomposition fragments can be evidenced by the decreased absorbance intensity in FTIR spectra. Furthermore, the presence of these fillers shows marginal influence on the nonisothermal crystallization behavior of PE. Additionally, the FMZH composite with hierarchical structure shows superior gas barrier function over pristine ZnO and montmorillonite. • Preparation of multi-component hybrid of FMZH is proposed. • With the aid of functionalized compound, the obtained hybrid shows good dispersion. • By adding FMZH fillers, the marked reductions in peak heat release rate are obtained. • This hierarchical structure of FMZH shows more superior gas barrier function. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
48. Rationally designed functionalized black phosphorus nanosheets as new fire hazard suppression material for polylactic acid.
- Author
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Zhou, Yifan, Huang, Jiali, Wang, Junling, Chu, Fukai, Xu, Zhoumei, Hu, Weizhao, and Hu, Yuan
- Subjects
- *
FIRE resistant polymers , *FIREFIGHTING , *POLYLACTIC acid , *FIREPROOFING agents , *HEAT release rates , *LITHIUM ions , *FIRE prevention , *PHOSPHORUS - Abstract
The black phosphorus (BP) nanosheets were firstly obtained by the modified lithium ion intercalation method and then functionalized by cetyl-trimethyl ammonium bromide (CTAB). Owing to the electrostatic interactions, the positively charged CTAB was successfully loaded onto the surface of negatively charged exfoliated BP and the BP-CTAB hybrids were finally obtained. It is found that BP-CTAB hybrids exhibits superior promotion effect on fire safety of Polylactic acid (PLA), which can be attributed to its typical layered structure, abundant phosphorus and good dispersion in matrix. Compared with neat PLA, the peak heat release rate (PHRR) of PLA composite with 2 wt% BP-CTAB decreases by 38.8%. Under the same loading of 2 wt%, the PLA/BP-CTAB2.0 shows better flame retardancy than PLA composites with BP or red phosphorus (RP). Moreover, the time to peak heat release rate (T PHRR) of PLA/BP-CTAB2.0 is postponed from 157 to 200 s. Derived from the uniform dispersion of BP-CTAB, the tensile strength of PLA composites are also improved. Meanwhile, the air stability of BP-CTAB in polymer is investigated. It is observed that the A g 1/A g 2 value of BP-CTAB only decreases from 0.57 to 0.54 even after immersion in water for one month, which can be ascribed to the double coating of polymer matrix and CTAB. This work enriches the method of exfoliating BP, and first explores the influence of BP on the flame retardant and mechanical properties of PLA. • Modified lithium ion intercalation method enriches the way of exfoliating BP. • BP-CTAB nanohybrids exhibit significant effect on decrease in PHRR and postponing in T PHRR. • BP-CTAB nanohybrids significantly improve thermal stability of PLA composites. • The air stability of BP-Li nanosheets is enhanced by the double coating of polymer matrix and CTAB. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
49. Controlled self-template synthesis of manganese-based cuprous oxide nanoplates towards improved fire safety properties of epoxy composites.
- Author
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Wang, Wei, Yuan, Yao, Yu, Bin, Liew, Kim Meow, Yuen, Richard K.K., Liu, Jiajia, and Hu, Yuan
- Subjects
- *
FIRE prevention , *EPOXY resins , *HEAT release rates , *CUPROUS oxide , *ENTHALPY , *AEROSPACE materials - Abstract
• Cuprous oxides with sheet morphology (Mn@Cu 2 O-M nanosheets) are rationally designed and successfully prepared. • The prepared Mn@Cu 2 O-M sheets could endow epoxy composites with high flame retardancy and smoke suppression properties. • The mechanism are probably due to the physical barrier effect and catalytic carbonization awarded by Mn@Cu 2 O-M sheets. To date epoxy resins have been extensively used in the field of chemical engineering, aerospace and building materials. Nevertheless, the utilization of flammable epoxy resins has posed a huge threat to lives and properties, which restricted their applications. In this work, manganese-based cuprous oxides two-dimensional nanosheets (Mn@Cu 2 O-M) are rationally designed and successfully prepared to improve the toxic effluent elimination of epoxy resin. The fire safety properties of the prepared Mn@Cu 2 O-M based nanocomposites improved the heat release rate (<35 %) and total heat release (<40 %) compared to the control epoxy. Moreover, the production of smoke and toxic volatiles of the composites with Mn@Cu 2 O-M nanosheets is significantly reduced. The mechanism investigations indicate that the improved flame retardancy and toxic effluent elimination of epoxy composites are attributed to the physical barrier effect and catalytic carbonization awarded by Mn@Cu 2 O-M nanosheets during burning. This work provides a promising strategy to develop eco-friendly, efficient and fire-safe polymers by both physical barrier effect and catalytic carbonization. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
50. Combination of black phosphorus nanosheets and MCNTs via phosphorus[sbnd]carbon bonds for reducing the flammability of air stable epoxy resin nanocomposites.
- Author
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Zou, Bin, Qiu, Shuilai, Ren, Xiyun, Zhou, Yifan, Zhou, Feng, Xu, Zhoumei, Zhao, Zhixin, Song, Lei, Hu, Yuan, and Gong, Xinglong
- Subjects
- *
FIRE resistant polymers , *FIREPROOFING agents , *EPOXY resins , *HEAT release rates , *FLAMMABILITY , *FIRE prevention - Abstract
• BP nanosheets and MCNTs were combinated via stable phosphorus carbon bonds. • EP/BP-MCNTs exhibits low PHRR, THR, SPR, TSR, FGI and smoke toxicity. • BP-MCNTs possessed naao-barrier, synergistic charring and radicals trapping effect. • MCNTs bonding and EP matrix wrapping improve the air-stable of EP/BP-MCNTs. As a rising star of two-dimensional material, black phosphorus (BP) has attracted tremendous attention in applications of photovoltaics, transistors and batteries due to its unique characteristics. Inspiring, we developed a simple strategy to fabricate BP-MCNTs as highly promising inorganic phosphorus-based flame retardant. After incorporation 2 wt% BP-MCNTs11(the mass ratio of BP:MCNTs=1:1) nanohybrid, the peak of heat release rate and total heat release of EP nanocomposites reduced by 55.81% and 41.17% at a phosphorus content of only 1 wt%, and the comprehensive index FGI for evaluating the flame retardant of materials decreased from 17.35 to 6.97. In addition, the typical flammable volatile are suppressed significantly, and the first stage of carbon monoxide release is disappeared. The improvement of fire safety and inhibition of smoke toxicity could be attributed to the the synergistic effects of nano-barrier, catalytic charring and radicals trapping of BP-MCNTs nanohybrid. More importantly, BP hybrid with MCNTs and wrapped in EP matrix which formed effective isolation protection against the ambient degradation. Raman spectra and SEM results confirmed that EP/BP-MCNTs performed enhanced ambient stability than EP/BP-BS nanocomposites after three months. This study demonstrates its great potential for preparation of air-stable BP based nanocomposites with enhanced fire safety. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
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