132 results on '"Self-healing polymer"'
Search Results
2. Near-infrared light-induced sustainable self-healing polymer composites from glass fabric reinforced benzoxazine/epoxy copolymers
- Author
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Mora, Phattarin, Rimdusit, Sarawut, and Jubsilp, Chanchira
- Published
- 2024
- Full Text
- View/download PDF
3. Nanoscale Encapsulation of Sulfur Cathodes via Self-Healing and Polar Synergistic Multifunctional Coating for High-Performance Li–S Batteries.
- Author
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Yang, Zhao, Patel, Twinkal, Thinphang-Nga, Anna, Nizami, Ameer, Park, Junyoung, Ye, Zhibin, Jung, Hyun Wook, Gauvin, Raynald, Peslherbe, Gilles Herve, Oh, Jung Kwon, and Li, Xia
- Abstract
The development of lithium–sulfur (Li–S) batteries is plagued by serious polysulfide shuttling, sluggish redox reaction kinetics, and low sulfur utilization. In this work, a nanoscale poly-(hindered urea) (PHU) coating with self-healability is designed for sulfur cathodes to achieve an improved electrochemical performance. The as-prepared polymer coating in a thickness of about 3 nm uniformly on the surface of the nanoscale sulfur/carbon (S/C) particles acts as a physical barrier to effectively encapsulate and accumulate lithium polysulfide (LiPS) inside the S/C nanoscale particles and thus facilitates the rapid conversion of LiPSs. In addition, the dynamic and reversible self-healing hindered urea bonds (HUBs) endow the PHU coating layer with the ability to maintain structural integrity and stability even after numerous cycles of volume expansion and shrinkage from nanoscale particles to the electrode level. More importantly, the polar groups carried by the PHU polymer exert a strong adsorption effect on LiPSs, thus further hindering the shuttling of LiPSs. Consequently, the nanoarchitecture with PHU coating layer exhibits impressive cycle stability (maintaining 82.8% capacity retention after 150 cycles at 0.5 C) and outstanding rate performance (capacity retention of 623.9 mAh g
–1 at 2 C). Furthermore, even under a high sulfur loading of 8.47 mg cm–1 , a high areal-specific capacity of 6.4 mAh cm–2 is still delivered. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
4. Self‐Healing Optical Structures for Light‐Trapping in Perovskite Solar Cells.
- Author
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Wan, Guanxiang, Alvianto, Ezra, Guo, Hongchen, Wang, Xi, Shin, Young‐Eun, Liang, Fang‐Cheng, Hou, Yi, and Tee, Benjamin C. K.
- Subjects
- *
SOLAR cells , *OPTOELECTRONIC devices , *YOUNG'S modulus , *SHORT circuits , *PEROVSKITE , *PHOTOVOLTAIC power systems - Abstract
Self‐healing transparent polymers are advantageous for various optoelectronic devices to improve resilience and durability. However, most of these materials have been applied only as flat films and do not address the need for optical structures that can manipulate light. Here optical microstructures embossed on a self‐healing polyurea film are presented which can autonomously recover from damage in ambient conditions. The polyurea film have a high optical transmittance above 90% and haze below 1.3%, and Young's modulus of 3.4 MPa. When applied as a protective light‐trapping layer for perovskite solar cells, the champion device shows improved short circuit current density from 23.7 to 25.0 mA·cm−2, and power conversion efficiency from 21.5% to 23.0%. Furthermore, the solar cell with the light‐trapping layer has improved impact resistance and can recover its performance after being scratched. It is envisioned that self‐healing optical structures can be realized for different geometries and materials in a range of optoelectronic applications to produce resilient and durable devices. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
5. Creep-Resistant Covalent Adaptable Networks with Excellent Self-Healing and Reprocessing Performance via Phase-Locked Dynamic Covalent Benzopyrazole-Urea Bonds.
- Author
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Xie, Miao, Wang, Xiao-Rong, Wang, Zhan-Hua, and Xia, He-Sheng
- Subjects
- *
PLASTIC scrap , *SELF-healing materials , *COVALENT bonds , *ADDITION reactions , *PHASE separation , *POLYMER networks - Abstract
Covalent adaptive networks (CANs) are capable of undergoing segment rearrangement after being heated, which endows the materials with excellent self-healing and reprocessing performance, providing an efficient solution to the environment pollution caused by the plastic wastes. The main challenge remains in developing CANs with both excellent reprocessing performance and creep-resistance property. In this study, a series of CANs containing dynamic covalent benzopyrazole-urea bonds were developed based on the addition reaction between benzopyrazole and isocyanate groups. DFT calculation confirmed that relatively low dissociation energy is obtained through undergoing a five-member ring transition state, confirming excellent dynamic property of the benzopyrazole-urea bonds. As verified by the FTIR results, this nice dynamic property can be well maintained after incorporating the benzopyrazole-urea bonds into polymer networks. Excellent self-healing and reprocessing performance is observed by the 3-ABP/PDMS elastomers owing to the dynamic benzopyrazole-urea bonds. Phase separation induced by the aggregation of the hard segments locked the benzopyrazole-urea bonds, which also makes the elastomers display excellent creep-resistance performance. This hard phase locking strategy provides an efficient approach to design CANs materials with both excellent reprocessing and creep-resistance performance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
6. Autonomous self‐healing 3D micro‐suction adhesives for multi‐layered amphibious soft skin electronics.
- Author
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Lim, Dohyun, Jeong, Min Woo, Min, Hyeongho, Lee, Yeon Soo, Hwang, Gui Won, Jeon, Seung Hwan, Jung, Kyu Ho, Vo, Ngoc Thanh Phuong, Kim, Min‐Seok, Kim, Da Wan, Oh, Jin Young, and Pang, Changhyun
- Subjects
GOLD electrodes ,STRUCTURAL models ,STRUCTURAL design ,ROUGH surfaces ,HUMAN body ,BIOMEDICAL adhesives - Abstract
Autonomously self‐healing, reversible, and soft adhesive microarchitectures and structured electric elements could be important features in stable and versatile bioelectronic devices adhere to complex surfaces of the human body (rough, dry, wet, and vulnerable). In this study, we propose an autonomous self‐healing multi‐layered adhesive patch inspired by the octopus, which possess self‐healing and robust adhesion properties in dry/underwater conditions. To implement autonomously self‐healing octopus‐inspired architectures, a dynamic polymer reflow model based on structural and material design suggests criteria for three‐dimensional patterning self‐healing elastomers. In addition, self‐healing multi‐layered microstructures with different moduli endows efficient self‐healing ability, human‐friendly reversible bio‐adhesion, and stable mechanical deformability. Through programmed molecular behavior of microlevel hybrid multiscale architectures, the bioinspired adhesive patch exhibited robust adhesion against rough skin surface under both dry and underwater conditions while enabling autonomous adhesion restoring performance after damaged (over 95% healing efficiency under both conditions for 24 h at 30°C). Finally, we developed a self‐healing skin‐mountable adhesive electronics with repeated attachment and minimal skin irritation by laminating thin gold electrodes on octopus‐like structures. Based on the robust adhesion and intimate contact with skin, we successfully obtained reliable measurements during dynamic motion under dry, wet, and damaged conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
7. Synthesis and application of Aromatic Schiff base waterborne polyurethane as visible-light triggered self-healing polymer and anticorrosion coating using h-BN/GO/NiO nano-composite
- Author
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Masoumeh Kianfar, Mir Saeed Seyed Dorraji, Mohammad Hossein Rasoulifard, Alireza Rahimi, and Sohrab Rahmani
- Subjects
Self-healing polymer ,Aromatic schiff base bond ,Anti-corrosion ,Nano-composite ,Polymers and polymer manufacture ,TP1080-1185 - Abstract
Herein, a self-healing waterborne polyurethane (WPU) based on a novel visible light-stimulated healing agent from the aromatic Schiff base family (SBWPU) was synthesized. Moreover, this polymer exhibited remarkable mechanical properties, making it an ideal matrix for the preparation of a new nano-composite coating using hexagonal-boron nitride/graphene oxide/nickel oxide (h-BN/GO/NiO) nano-composite for anti-corrosion applications. SBWPU containing 15 wt % of synthesized healing agent (SBWPU-15) demonstrated favorable healing properties (80.03 %) under a visible light lamp after 24 h (at ambient temperature). SBWPU containing 20 % of the healing agent (SBWPU-20) showed high mechanical properties (20.80 MPa) and an increase in its hydrophobic properties. Additionally, its water absorption rate decreased, making it an attractive option as a polymer matrix for anti-corrosion coating applications. The nano-composite coatings (CSBWPU) were formulated by introducing varying amounts of h-BN/GO/NiO into the SBWPU-20. The coatings displayed an increase in contact angle and a decrease in water absorption rate. The electrochemical impedance spectroscopy (EIS) results revealed that the 0.75-CSBWPU, containing 0.75 % nano-composite, had the highest corrosion resistance (1.58 × 1010 Ω cm2) after 90 days of immersion in seawater. This work offers a potentially helpful concept for developing an eco-friendly, secure, uncomplicated accessibility self-healing polymeric system with controllable mechanical features, which are also favorable for designing novel corrosion protection composite coatings.
- Published
- 2024
- Full Text
- View/download PDF
8. A nerve-adhesive stretchable electrode for stable neural signal recording and stimulation: A nerve-adhesive stretchable electrode for stable neural signal
- Author
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Park, Jaehyun, Seong, Duhwan, Choi, Heewon, Lee, Jaebeom, Song, Jihyang, Shin, Mikyung, and Son, Donghee
- Published
- 2025
- Full Text
- View/download PDF
9. Fast thermo-responsive thermoset self-healing polymers based on bio-derived Benzoxazine/Epoxidized castor oil copolymers for coating applications
- Author
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Phattarin Mora, Sarawut Rimdusit, and Chanchira Jubsilp
- Subjects
Self-healing polymer ,Polybenzoxazine ,Epoxidized castor oil ,Bio-derived polymer ,Numerical simulation ,Chemistry ,QD1-999 - Abstract
This work emphasized on development of a novel bio-derived self-healing copolymer fabricated from benzoxazine and epoxy resins by varying weight ratios. The bio-derived benzoxazine (E-fa) acted as a healing agent was copolymerized with bio-derived epoxy resin namely epoxidized castor oil (ECO). Three main essential properties of the developed copolymer were systematically investigated: thermal property, mechanical property, and self-healing capacity. The numerical simulation was also used to study and predict the ability of roof coatings based on the developed copolymers. The results showed that the reversible crosslinking reaction occurred and resulted in state transition of the copolymers. The mechanical property i.e., tensile strength and peel strength to stainless steel substrate, were substantially improved with the incorporation of ECO. The increase in E-fa contents can enhance the thermos-responsive healing performance of the copolymers up to 93% via reversible reactions with rapid surface damage healed within 2 min. Furthermore, the experimental and numerical results revealed that the thermo-responsive thermoset self-healing bio-derived benzoxazine/epoxy copolymers have a potential use in coating applications required fast self-healing performance and good mechanical properties.
- Published
- 2024
- Full Text
- View/download PDF
10. Autonomous self‐healing 3D micro‐suction adhesives for multi‐layered amphibious soft skin electronics
- Author
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Dohyun Lim, Min Woo Jeong, Hyeongho Min, Yeon Soo Lee, Gui Won Hwang, Seung Hwan Jeon, Kyu Ho Jung, Ngoc Thanh Phuong Vo, Min‐Seok Kim, Da Wan Kim, Jin Young Oh, and Changhyun Pang
- Subjects
biomimetics ,dry adhesive ,self‐healing polymer ,stretchable electronics ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Information technology ,T58.5-58.64 - Abstract
Abstract Autonomously self‐healing, reversible, and soft adhesive microarchitectures and structured electric elements could be important features in stable and versatile bioelectronic devices adhere to complex surfaces of the human body (rough, dry, wet, and vulnerable). In this study, we propose an autonomous self‐healing multi‐layered adhesive patch inspired by the octopus, which possess self‐healing and robust adhesion properties in dry/underwater conditions. To implement autonomously self‐healing octopus‐inspired architectures, a dynamic polymer reflow model based on structural and material design suggests criteria for three‐dimensional patterning self‐healing elastomers. In addition, self‐healing multi‐layered microstructures with different moduli endows efficient self‐healing ability, human‐friendly reversible bio‐adhesion, and stable mechanical deformability. Through programmed molecular behavior of microlevel hybrid multiscale architectures, the bioinspired adhesive patch exhibited robust adhesion against rough skin surface under both dry and underwater conditions while enabling autonomous adhesion restoring performance after damaged (over 95% healing efficiency under both conditions for 24 h at 30°C). Finally, we developed a self‐healing skin‐mountable adhesive electronics with repeated attachment and minimal skin irritation by laminating thin gold electrodes on octopus‐like structures. Based on the robust adhesion and intimate contact with skin, we successfully obtained reliable measurements during dynamic motion under dry, wet, and damaged conditions.
- Published
- 2024
- Full Text
- View/download PDF
11. Self-healing carboxylic acid-cured epoxy networks driven by the cyclodextrin–cyclohexane host–guest interaction.
- Author
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Kurihara, Risa, Ogawa, Yamato, Sugane, Kaito, and Shibata, Mitsuhiro
- Subjects
- *
POLYMER networks , *SORBITOL , *EPOXY resins , *GLASS transition temperature , *ETHYLENE glycol , *CYCLODEXTRINS , *POTASSIUM hydroxide - Abstract
The reaction of β-cyclodextrin (β-CD) and bromoacetic acid in the presence of potassium hydroxide produced a carboxymethylated β-CD (CMβCD) with a substitution degree of 3.0. Thermal curing reactions of sorbitol polyglycidyl ether with CMβCD, cyclohexanecarboxylic acid, and poly(ethylene glycol) bis(carboxymethyl) ether (PEGBC) at 1/1 epoxy/carboxylic acid molar ratios produced carboxylic acid-cured epoxy networks (SCCPB) incorporating the cyclodextrin-cyclohexane host–guest moieties. The FT–IR and gel fraction measurements for the cured products revealed that polymer networks were formed by the reaction between epoxy and carboxy groups. With increasing PEGBC content, the glass transition temperature (Tg), tensile strength, and tensile modulus of SCCPB films decreased. SCCPB films with relatively high PEGBC contents demonstrated self-healing properties after being treated at room temperature for 30 s, whereas SCCPB films with relatively low PEGBC contents did not. The SCCPB film with the highest PEGBC content exhibited an excellent healing efficiency (98%) based on the recovery rate of the tensile strength, when healed at 60 °C for 24 h. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
12. Self-healing castor oil-based polyurethane networks featuring cyclodextrin–adamantane host–guest interactions.
- Author
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Sekiya, Takumi and Shibata, Mitsuhiro
- Subjects
- *
SELF-healing materials , *CASTOR oil , *POLYURETHANES , *FOURIER transform infrared spectroscopy , *HEXAMETHYLENE diisocyanate , *GLASS transition temperature , *CYCLODEXTRINS - Abstract
Urethanization of castor oil (CO), β-cyclodextrin (CD), and 1-adamantanol (AdOH) with hexamethylene diisocyanate (HDI) at a CD/AdOH molar ratio of 1:1 and various feed CO fractions produced castor oil-based polyurethane network films (CAPUs) incorporating cyclodextrin and adamantane units as host and guest components, respectively. For comparison, similar urethanization reactions were performed with CO/CD/HDI and CO/AdOH/HDI to produce network films that lacked guest or host moieties (CDPU and ADPU, respectively). The results of Fourier transform infrared spectroscopy and gel fraction measurements confirmed the formation of polyurethane networks. The glass transition temperatures, tensile strengths, and tensile moduli of the network films increased with decreasing CO fractions. All CAPU films demonstrated healing properties at room temperature; however, the CDPU and ADPU films did not. The healing efficiency also increased with decreasing CO fraction. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
13. Preparation of Epoxy Resin with Disulfide-Containing Curing Agent and Its Application in Self-Healing Coating.
- Author
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Wang, Baolei, Li, Zewei, Liu, Xinru, Li, Lulu, Yu, Jianxiang, Li, Shuang, Guo, Gaiping, Gao, Dahai, and Dai, Yuhua
- Subjects
- *
EPOXY resins , *CROSSLINKED polymers , *SELF-healing materials , *POLYMER networks , *EPOXY coatings , *CURING , *HYDROGEN bonding , *COVALENT bonds - Abstract
Intrinsic self-healing polymers via dynamic covalent bonds have been attracting extensive attention because of their repeatable self-healing property. Herein, a novel self-healing epoxy resin was synthesized with disulfide-containing curing agent via the condensation of dimethyl 3,3′-dithiodipropionate (DTPA) and polyether amine (PEA). Therefore, in the structure of cured resin, flexible molecular chains and disulfide bonds were imported into the cross-linked polymer networks for triggering self-healing performance. The self-healing reaction of cracked samples was realized under a mild condition (60 °C for 6 h). The distribution of flexible polymer segments, disulfide bonds and hydrogen bonds in cross-linked networks plays a great role in the self-healing process of prepared resins. The molar ratio of PEA and DTPA strongly affects the mechanical performance and self-healing property. Especially when that molar ratio of PEA to DTPA is 2, the cured self-healing resin sample showed great ultimate elongation (795%) and excellent healing efficiency (98%). The products can be used as an organic coating, in which the crack could self-repair during a limited time. The corrosion resistance of a typical cure coating sample has been testified by an immersion experiment and electrochemistry impedance spectrum (EIS). This work provided a simple and low-cost route to prepare a self-healing coating for prolonging the service life of conventional epoxy coatings. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
14. Preparation and Characterization of Poly(Acrylic Acid)-Based Self-Healing Hydrogel for 3D Shape Fabrication via Extrusion-Based 3D Printing.
- Author
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Shin, Woohyeon and Chung, Kyeongwoon
- Subjects
- *
THREE-dimensional printing , *RHEOLOGY , *ACRYLIC acid , *SELF-healing materials - Abstract
The three-dimensional (3D) printing of hydrogel is an issue of interest in various applications to build optimized 3D structured devices beyond 2D-shaped conventional structures such as film or mesh. The materials design for the hydrogel, as well as the resulting rheological properties, largely affect its applicability in extrusion-based 3D printing. Here, we prepared a new poly(acrylic acid)-based self-healing hydrogel by controlling the hydrogel design factors based on a defined material design window in terms of rheological properties for application in extrusion-based 3D printing. The hydrogel is designed with a poly(acrylic acid) main chain with a 1.0 mol% covalent crosslinker and 2.0 mol% dynamic crosslinker, and is successfully prepared based on radical polymerization utilizing ammonium persulfate as a thermal initiator. With the prepared poly(acrylic acid)-based hydrogel, self-healing characteristics, rheological characteristics, and 3D printing applicability are deeply investigated. The hydrogel spontaneously heals mechanical damage within 30 min and exhibits appropriate rheological characteristics, including G′~1075 Pa and tan δ~0.12, for extrusion-based 3D printing. Upon application in 3D printing, various 3D structures of hydrogel were successfully fabricated without showing structural deformation during the 3D printing process. Furthermore, the 3D-printed hydrogel structures exhibited excellent dimensional accuracy of the printed shape compared to the designed 3D structure. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
15. Synthesis, Properties, and Function of Self-Healing Polymer-Based on Eugenol
- Author
-
Erwin Abdul Rahim
- Subjects
self-healing polymer ,eugenol ,catalyst ,biodiesel production ,Chemistry ,QD1-999 - Abstract
Eugenol-based self-healing polymers were synthesized in a very short time of 94–159 s. Polymerization of eugenol catalyzed by H2SO4-CH3COOH yielded the corresponding self-healing polymers in quantitative yields in the range of molecular weight (5.18–15.10) × 105 g/mol. The polymer exhibited self-healing behavior at room temperature due to hydrogen bonds between the hydroxyl groups of polyeugenol and the hydroxyl groups of sulfuric acid. This material can function as a polyelectrolyte and a novel self-healing catalyst for biodiesel production.
- Published
- 2022
- Full Text
- View/download PDF
16. Closed-loop Recyclable Lithium and Sodium Conducting Covalent Adaptable Networks.
- Author
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Chen H, Wayment LJ, Jiang H, Lei Z, Huang S, Ley A, Yue Z, Yuan Z, Jin Y, Yu K, and Zhang W
- Abstract
Within the past two decades, covalent adaptable networks (CANs) have emerged as a novel class of dynamically crosslinked polymers, combining the benefits of thermosets and thermoplastics. Although some CANs with charged side chains have been reported, CANs with negatively charged backbones remain very limited. The integration of permanent charge into the backbones upon their formation could open up important new applications. Here, we introduce a series of aliphatic spiroborate-linked ionic covalent adaptable networks (ICANs), representing a new category of dynamic ionomer thermosets. These ICANs were synthesized using a catalyst-free, scalable, and environment-friendly method. Incorporating lithium or sodium as counter cations in these networks yielded promising ion conductivity without the need of plasticizers. The dynamic nature of the spiroborate linkages in these materials allows for rapid reprocessing and recycling under moderate conditions. Furthermore, their potential as flexible solid-state electrolytes is demonstrated in a device that maintained robust conducting performance under extreme physical deformation, coupled with effective self-healing properties. This research opens new possibilities for future development of dynamic ionomer thermosets and their potential applications in flexible electronic devices., (© 2025 Wiley‐VCH GmbH.)
- Published
- 2025
- Full Text
- View/download PDF
17. Fast thermo-responsive thermoset self-healing polymers based on bio-derived Benzoxazine/Epoxidized castor oil copolymers for coating applications.
- Author
-
Mora, Phattarin, Rimdusit, Sarawut, and Jubsilp, Chanchira
- Abstract
This work emphasized on development of a novel bio-derived self-healing copolymer fabricated from benzoxazine and epoxy resins by varying weight ratios. The bio-derived benzoxazine (E-fa) acted as a healing agent was copolymerized with bio-derived epoxy resin namely epoxidized castor oil (ECO). Three main essential properties of the developed copolymer were systematically investigated: thermal property, mechanical property, and self-healing capacity. The numerical simulation was also used to study and predict the ability of roof coatings based on the developed copolymers. The results showed that the reversible crosslinking reaction occurred and resulted in state transition of the copolymers. The mechanical property i.e., tensile strength and peel strength to stainless steel substrate, were substantially improved with the incorporation of ECO. The increase in E-fa contents can enhance the thermos-responsive healing performance of the copolymers up to 93% via reversible reactions with rapid surface damage healed within 2 min. Furthermore, the experimental and numerical results revealed that the thermo-responsive thermoset self-healing bio-derived benzoxazine/epoxy copolymers have a potential use in coating applications required fast self-healing performance and good mechanical properties. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
18. Research progress of self-repairing polymers in electrochemical energy storage devices
- Author
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LIU Zi-yang, LI Yang, LIU Xing-jiang, and XU Qiang
- Subjects
self-healing polymer ,electrochemical energy storage ,electrode ,electrolyte ,interface ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Self-healing polymer materials are able to self-repair damage and recover themselves after cracks generating to maintain their structural and functional integrity. According to whether additional repair agent is added, self-healing polymers are mainly divided into two categories, namely extrinsic- and intrinsic-based polymers.The key materials of electrochemical energy storage devices will experience irreversible mechanical damage in extreme condition applications, for example, the energy storage device more prone to physical damage inwearable devices during the multiple bending and deformation processes. These problems severely reduce the stability of energy storage and delivery, and shorten the life of the devices. Therefore, the application of self-healing polymers in electrochemical energy storage devices to improve the stability and life of devices has become one of the research hotspots in recent years. Herein,this article summarizes the repair mechanism of self-healing polymer materials (capsule-based, vascular-based, and intrinsic polymers), with main focus on intrinsic self-healing polymer and its research progress in the field of electrochemical energy storage, which based on molecular interactions to achieve multi-time reversible healing without any additional repair agent.The self-healing electrode and electrolyte system were reviewed respectively, and then the self-healing mechanism and its influence on the electrochemical performance of energy storage devices were described. The research progress of self-healing functional polymer as high specific energy electrode binder, interface modification layer and self-healing electrolyte were summarized in detail. Finally, the future perspectives regarding the future development of self-healing polymer materials were also discussed.
- Published
- 2021
- Full Text
- View/download PDF
19. Manufacturing challenges in self-healing technology for polymer composites — a review
- Author
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Paul Christopher JE, Mohamed TH Sultan, Chithirai Pon Selvan, Siva Irulappasamy, Faizal Mustapha, Adi Azriff Basri, and Syafiqah N.A. Safri
- Subjects
Self-healing polymer ,Capsule-based self-healing ,Vascular healing ,Intrinsic self-healing. ,Mining engineering. Metallurgy ,TN1-997 - Abstract
Self-healing polymer materials have the functional characteristics of curing when a crack penetrates the material. Damage response, healing ability and healing performance are the most important healing characteristics of a self-healing material. Self-healing in a material system is employed through different methodologies, such as capsulation, vascular filling and intrinsic healing systems. The most challenging factor in fabrication of self-healing material is the ‘carrier filling’ in both the vascular and capsule type healing methods. The self-healing is either autonomic or external, depending on the actuation of the healing. This paper reviews the healing agent carrier preparation for vascular self-healing systems and compares the vascular healing system with intrinsic self-healing. The review revealed that, in most cases, preparation of healing agents is challenging greater than understanding the healing mechanism. The behaviour of self-healing material under fatigue, impact, and ballistic characterisation is also reviewed towards suggesting the self healing materials for aerospace applications.
- Published
- 2020
- Full Text
- View/download PDF
20. Reconfigurable photoswitchable multistate fluorescent polymer-based information encryption toolbox
- Author
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Jiang, Jiawei, Zhang, Peisheng, Tian, Yong, Lin, Zhong, Zhang, Chonghua, Cui, Jiaxi, Chen, Jian, and Chen, Xudong
- Published
- 2023
- Full Text
- View/download PDF
21. 光感型“智能”聚合物的基本原理与分类.
- Author
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梁加璐, 马志民, 宋雨方, 郑文帅, 卢汇嘉, and 王晓蓉
- Abstract
Copyright of Journal of Petrochemical Universities / Shiyou Huagong Gaodeng Xuexiao Xuebao is the property of Journal Editorial Department Of Liaoning Shihua University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2022
- Full Text
- View/download PDF
22. Self-healing epoxy networks based on cyclodextrin–adamantane host–guest interactions.
- Author
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Sugane, Kaito, Maruoka, Yuji, and Shibata, Mitsuhiro
- Subjects
- *
POLYMER networks , *EPOXY resins , *GLASS transition temperature , *AMINO group , *ALIPHATIC amines , *TENSILE strength - Abstract
An aminated β-cyclodextrin (NCD) with an amine substitution degree of 16.4 was prepared through the thiol–ene reaction of allylated β-cyclodextrin and cysteamine hydrochloride. The thermal curing reactions of sorbitol polyglycidyl ether (SPE) with NCD, Jeffamine® ED-600 (JA, an aliphatic polyether amine), and adamantylamine (NAD) with a feed epoxy/NH2 ratio of 1:1 and feed NH2 molar ratios of NCD/JA/NAD = 1/1/1 and 1/2/1 produced epoxy-amine networks. The FT-IR and gel fraction measurements for the cured products revealed that polymer networks were formed by the reaction of epoxy and amino groups. The cured product with a higher JA content showed lower glass transition temperature (Tg), tensile strength, and tensile modulus results than those of the cured product with a lower JA content. Compared with the product with lower JA, the product with higher JA exhibited self-healing properties upon treatment at 60 °C. The self-healing driven by the NCD/NAD host–guest interaction was demonstrated as the self-healed sample returned to its original state after immersion in an ethanol solution of NAD. Moreover, the corresponding SPE/NCD/JA and SPE/JA/NAD cured products did not exhibit self-healing capacity. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
23. An extensive review of the repair behavior of smart self-healing polymer matrix composites
- Author
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Ghorbanpour Arani, Ali, Miralaei, Nasim, Farazin, Ashkan, and Mohammadimehr, Mehdi
- Published
- 2023
- Full Text
- View/download PDF
24. Study of healing effect on mechanical behavior of a smart asphalt pavement and permanent deformations due to a moving load in the framework of finite element analysis
- Author
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Roozbeh Eghbalpoor, Mostafa Baghani, Hamid Shahsavari, and Mohammad Shojaeifard
- Subjects
self-healing polymer ,damage recovery ,implicit discretization ,asphalt pavement ,Engineering design ,TA174 - Abstract
Self-healing polymers are a class of smart materials that have attracted many researchers due to their unique ability. These materials are able to heal part of the damage without the need to identify the site. In order to study the behavior of these polymers, a thermodynamically consistent model is proposed to predict the mechanical response. Along with this, the implicit time-discrete form of the constitutive model is presented in order to utilize in ABAQUS software by UMAT subroutine. In the discretization, the Newton-Raphson method has been used to update internal variables such as viscoplastic strain components. Considering the calibration of the material parameters by the experimental results of the asphalt sample, the movement of vehicle on the desired pavement has simulated. In this research, a detailed explanation of how to perform the finite element analysis of mechanical behavior of asphalt pavements is presented using constitutive model and its implicit discretization. In the following, its validation with existing experimental results is also carried out. Next, a comparison between the simulations is performed without and with healing effect. From the results of finite element analysis, the important role of healing in the life of the pavement can be noted, which can increase the recovery of damage up to 20%.
- Published
- 2019
- Full Text
- View/download PDF
25. Biochemistry and Structure-Function Relationships in the Proteinaceous Egg Capsules of Busycotypus canaliculatus
- Author
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Wasko, Stephen S.
- Subjects
egg capsule ,nidamental gland ,protein ,whelk ,elasticity ,self-healing polymer ,electrospinning - Abstract
The designs of highly extensible soft materials in nature are of a fundamental interest to engineers so that insights into the production of modern, synthetic materials can be gleaned. Marine gastropods of the genus Busycotypus produce a protein based elastomer which possesses a unique combination of stiffness and extensibility. Furthermore, this material displays shape-memory/self-healing properties that are unmatched in synthetic engineering systems. Four variants of the precursor protein components of the egg capsules are highly unique in their amino acid sequences, showing no homology to any known protein families. These proteins are strongly a-helicaì in nature, and can self-assemble into nanometer scaled fibers in vitro. The remarkable reversibly extensibility of the bulk material is dictated not by entropie forces, but rather by a crystalline phase transition within the protein components when the material is put under tension. Proteins shift from a-helix to ß-sheet, and it is this uncoiling of helices within the polymer backbone that allows for the extensibility of the egg capsules. This transition is reversible, as when loads are removed and the material is allowed to relax, it returns to its original a-helical conformation. When examined more closely, it is shown that this a«->>ß transition is a multi-step transformation which involves first the uncoiling of crystalline a-helices into non-crystalline random coils before these then lock into ß-sheets. These different steps dictate changes in the mechanical properties of the material as this transition is occurring. Furthermore, the supramolecular structure of how the individual proteins interact in the intact material also changes throughout tension/relaxation cycles. These structural changes also have effects on the bulk mechanical properties of the material. This work explores in detail the structure-function relationships of Busycotypus egg capsule material mentioned above.
- Published
- 2010
26. 自修复聚合物在电化学储能 领域的研究进展.
- Author
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刘梓洋, 李 杨, 刘兴江, and 徐 强
- Abstract
Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2021
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27. Ion-conductive self-healing hydrogels based on an interpenetrating polymer network for a multimodal sensor.
- Author
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Shin, Sung-Ho, Lee, Woojoo, Kim, Seon-Mi, Lee, Minkyung, Koo, Jun Mo, Hwang, Sung Yeon, Oh, Dongyeop X., and Park, Jeyoung
- Subjects
- *
POLYMER networks , *SENSOR networks , *CONDUCTING polymers , *IONIC conductivity , *ACRYLIC acid , *HYDROGELS - Abstract
• A self-healing hydrogel is developed based on an interpenetrating polymer network strategy. • Chemically/ionically cross-linked Fe3+/PAA and physically cross-linked PVA organize the IPN. • The hydrogel satisfies the three capabilities of robustness, self-healing, and conductivity. • The multimodal sensing capabilities for strain, pressure, and temperature are determined. • A dual sensor attached to a finger simultaneously detects folding/pressure-motions. Conductive self-healing polymer hydrogel and related soft sensor devices are receiving considerable attention from academia to industry because of their impacts on the lifetime and ergonomic design of soft robotics, prosthesis, and health monitoring systems. However, the development of such a material has thus far been limited considering performances and accessibility. Herein, robustness, self-healing, and conductivity for soft electronic skin are realized by an interpenetrating polymer network (IPN) system based on chemical/ionic cross-linked poly(acrylic acid) containing ferric ions, intercalated with physically cross-linked poly(vinyl alcohol). This IPN hydrogel successfully satisfies all three aforementioned capabilities; elongation at break greater than 1400%; recovery to original mechanical properties greater than 80% after 24 h; and 0.14 S m−1 of ionic conductivity, which is electrically healable. Such ionic conductivity of hydrogels enables multimodal sensing capabilities, i.e., for strain, pressure, and temperature. Particularly, a uniquely designed dual sensor attached to a finger simultaneously detects mechanical folding and pressure changes independently and can undergo large deformation 1000 times repeated and heating up to 90 °C. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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28. Diels-Alder based epoxy matrix and interfacial healing of bismaleimide grafted GNP infused hybrid nanocomposites.
- Author
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Khan, Nazrul Islam, Halder, Sudipta, and Wang, Jialai
- Subjects
- *
EPOXY resins , *SELF-healing materials , *INTERFACES (Physical sciences) , *MALEIMIDES , *NANOCOMPOSITE materials - Abstract
Abstract In this work, we report matrix and interfacial healing capabilities for hybrid DA-based polymer nanocomposites. Thermo-reversible self-healing nanocomposites were prepared by reinforcing bismaleimide grafted graphite nanoplatelets (B-GNPs) in a DA-based hybrid polymer matrix (HPM). The maleimide functional moieties were found grafted on B-GNPs that form globular networked structures on the nanoplatelets. Data from the TG-DSC revealed increased exothermic peaks corresponding to DA and retro-DA bond formation due to the incorporation of B-GNPs in HPM. This indicates the formation of DA bonds proficient enough to establish self-healing at the interfaces of B-GNPs and HPM. We also found that incorporation of B-GNPs in HPM having 40 wt% irreversible epoxy resin (DA40) has the potential to uplift the mechanical stability along with self-healing efficiency demonstrating successful interfacial healing. The resulting B-GNPs reinforced nanocomposites of DA40 showed maximum healing efficiency of ~87% with multiple times healing capability. The tensile strength and modulus were also significantly increased by ~242% and ~41% in comparison to pristine DA40. This study espouses the potential use of B-GNPs for multiple interfacial healing along with matrix healing of hybrid polymer nanocomposites. Highlights • Self-healing of hybrid DA-based polymer nanocomposites has been successfully demonstrated. • Interfacial healing was demonstrated using bismaleimide functionalized GNPs. • The self-healing composites showed maximum healing efficiency of ~87%. • The composites can be healed up to 5 times without significant reduction of mechanical properties. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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29. Furan-based self-healing breathable elastomer coating on polylactide fabric.
- Author
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Ryu, Yeon Sung, Oh, Kyung Wha, and Kim, Seong Hun
- Subjects
WATERPROOFING ,POLYMERS ,BUTENE ,POLYURETHANES ,COATING processes - Abstract
The demand for breathable waterproof products has increased with the need for functional sportswear. However, these membranes have a major weakness in the loss of performance over time. The self-healing polymer has attracted much attention as a solution to this problem. In this research, a bio-based self-healing polymer from furan-based polymer was synthesized to produce a sustainable waterproof membrane.The furan-based self-healing polymer was synthesized from poly(butylene furanoate) and bismaleimide via a Diels–Alder reaction and blended with bio polyurethane. Poly(ethylene glycol) was also blended to obtain nonporous breathable waterproofness. These synthesis processes were identified by spectroscopy analysis. To investigate the self-healing ability of the polymer, a film sample was sliced and reattached. These self-healing processes were observed and verified by morphological and mechanical analysis. These self-healing polymer films were successfully healed in 24 h. The polymer was coated on a polylactide fabric using a doctor blade. The self-healing ability of the membrane was investigated by breathable water repellency analysis and it was maintained after the coating process. The waterproofness and vapor permeability were also measured, and these results identified that the fabricated membrane has a possibility as a breathable waterproof fabric. Environmental performance was confirmed by the enzymatic degradation test. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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30. Highly entangled elastomer with ultra-fast self-healing capability and high mechanical strength.
- Author
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Li, Yuan, Feng, Xianqi, Sui, Cong, Xu, Jun, Zhao, Wenpeng, and Yan, Shouke
- Subjects
- *
MECHANICAL ability , *SELF-healing materials , *HEALING , *POLYMERS , *MONOMERS , *ARTIFICIAL muscles , *ELASTOMERS - Abstract
• The entanglements improve the strength of the polymer from 4.4 MPa to 9.1 MPa. • The resultant elastomer exhibits a strength of 18.4 MPa with a healing efficiency of 86.2 % after 30 s healing. • The elastomer can reversibly lift a 1000 times weight of its own with a strain of 28% upon heating–cooling cycle. Self-healing polymeric material, which can heal the cracks repeatedly and thus definitely prolong their lifetime in practical applications, has attracted intensive interesting in recent years. However, it is still a great challenge to both achieve fast self-healing ability and high mechanical strength. Considering the mechanism of fast self-healing is the re-bonding of dynamic bonds in the fracture surfaces, the dense physical cross-linking might be a good option for fast self-healing polymer to solve the trade-off between self-healing ability and mechanical strength. To this end, the highly entangled polymer chains are thereby introduced to improve the mechanical strength of the elastomer by simply increasing the monomer concentration. As expected, the mechanical strength of the resultant elastomers increases with monomer concentration, accompanied by a slight decline in self-healing ability. In addition, further increment of the mechanical strength to 18.4 Mpa is achieved by introducing anisotropic structure into the highly entangled polymers by pre-stretching. Most importantly, the resultant polymer exhibits high recovery and fast self-healing ability with a healing efficiency of 86.2 % after only 30 s healing at room temperature. Moreover, the highly entangled polymer chains also improve the actuation performance of the elastomer with anisotropic structure, which can lift up about 1000 times of its own weight reversibly upon heating–cooling cycles with a maximum tensile stroke of ca. 28 %. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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31. Silver Nanoparticle-Assisted Electrochemically Exfoliated Graphene Inks Coated on PVA-Based Self-Healing Polymer Composites for Soft Electronics.
- Author
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Şimşek B, Ruhkopf J, Plachetka U, Rademacher N, Belete M, and Lemme MC
- Abstract
Smart sensors with self-healing capabilities have recently aroused increasing interest in applications in soft electronics. However, challenges remain in balancing the sensors' self-healing and compatibility between their sensing and substrate layers. This study evaluated several self-healing polymer substrates and graphene ink-based strain-sensing coatings. The optimum electrochemically exfoliated graphene (e-graphene)/silver nanoparticle-coated tannic acid (TA)/superabsorbent polymer/graphene oxide (GO) blended poly(vinyl alcohol) polymer composites exhibited improvements of 47.1 and 39.2%, respectively, for the healing efficiency in a substrate crack area and in the graphene-based sensing layer due to conductive layer adhesion. While TA was found to improve healing efficiency on the coating surface by forming hydrogen bonds between the sensing and polymer layers, GO healed the polymer surface due to its ability to form bonds in the polymer matrix. The superabsorbent polymer was found to absorb excess water in e-graphene dispersion due to its host-guest interaction, while also reducing the coating thickness.
- Published
- 2024
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32. Structure evolution during order–disorder transitions in aliphatic polycarbonate based polyurethanes. Self-healing polymer.
- Author
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Matějka, Libor, Špírková, Milena, Dybal, Jiří, Kredatusová, Jana, Hodan, Jiří, Zhigunov, Alexander, and Šlouf, Miroslav
- Subjects
- *
POLYCARBONATES , *POLYURETHANES , *POLYMERS , *CYCLOHEXANE , *CRYSTALLINITY - Abstract
Graphical abstract Highlights • Aliphatic polycarbonate based polyurethane forms strong supramolecular structures. • Polyurethane involves three types of physical networks of different thermal stability. • Order–disorder transitions and entanglement formation depend on polymer composition. • Polyurethane is efficiently self-healed. Abstract The aliphatic polycarbonate based polyurethanes (PU) from poly(hexamethylene) carbonate diol (PC), hexamethylenediisocyanate and hexanediol were synthesized, characterized and designed as promising self healing polymers. The symmetrical linear PU structure containing the hexamethylene sequences results in a high degree of ordering and strong superstructures, manifested by a high crystallinity of the PC soft phase and a strong self-assembly of linear hard segments (HS). At the optimum composition, both supramolecular structures percolate resulting thus in the singnificant reinforcement. The PU, undergoing order–disorder transitions, involves three types of physical crosslinks with different thermal stability; PC crystalline phase, HS domains and in addition the entanglements. The structure evolution and reversible sol–gel transition during formation/breaking of the corresponding physical networks was followed by rheology, DSC and FTIR. The kinetics of build-up and stability of physical networks is governed by the content of HSs. The investigation contributed to the understanding and control of the thermal phase transitions of supramolecular structures in aliphatic PCPUs. The strong supramolecular structure undergoing order–disorder transitions, presence of thermally stable entanglement network and excellent mechanical properties make the PCPU suitable as a strong self-healing polymer. Two structural motifs are present: the thermally sensitive structure generating self-healing properties and the shape persistent entanglement network structure preventing the irreversible deformation. The efficient healing and restoration of the original structure and mechanical properties after damage of the polymer were checked by microscopy and tensile testing. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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33. Thermally reversible polymer networks for scratch resistance and scratch healing in automotive clear coats.
- Author
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Sung, Sujin, Kim, So Young, Lee, Tae Hee, Favaro, Gregory, Park, Young Il, Lee, Sang-Ho, Ahn, Jae Beom, Noh, Seung Man, and Kim, Jin Chul
- Subjects
- *
POLYMER networks , *MECHANICAL behavior of materials , *POLYURETHANES , *DIFFERENTIAL scanning calorimetry , *THERMOGRAVIMETRY - Abstract
Graphical abstract Highlights • Synthesis of a novel thermally-induced clear coat containing DA cycloadduct crosslinks. • Comprehensive analysis of reversible crosslinking/de-crosslinking. • Dynamic nature confirmed by combined rheological and thermal analysis. • Excellent mechanical and scratch-resistant properties. • Better scratch-healable performance over commercial clear coats. Abstract This study investigated the application of a thermally reversible polymer network fabricated using Diels-Alder (DA)/retro-DA (rDA) reactions for use as a scratch-healing automotive clear coat. For this purpose, a new scratch-healing poly(urethane acrylate) network containing a DA adduct unit (DA-CL) was prepared, and its material properties and scratch-healing performance were compared to the properties of a commercial clear coat system (C-CL). The thermally reversible crosslinking and de-crosslinking reactions among the DA-CL, via DA and rDA reactions, were systematically evaluated using in-situ oscillatory rheology coupled with FT-IR spectroscopy. The material properties of the DA-CL and C-CL materials, including the thermal stability, thermal transitions, hardness, and scratch resistance, were measured using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), nanoindentation, and nanoscratch test methods. The scratch-healing performance of the DA-CL was quantitatively characterized and compared to the performance of the C-CL using a nanoscratch tester equipped with an optical microscope (OM) and an atomic force microscope (AFM). The DA-CL polymer network exhibited superior scratch healing and scratch resistance compared to the C-CL polymer network. These data indicated that the DA self-healing polymer network is potentially useful as a scratch-healing clear coat for the automotive industry. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
34. Self-healing polyaniline-graphene oxides based electrodes with enhanced cycling stability.
- Author
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Wang, Weijie, Yan, Jian, Liu, Jiaqin, Ou, Dawei, Qin, Qingqing, Lan, Binbin, Ning, Yu, Zhou, Dan, and Wu, Yucheng
- Subjects
- *
POLYANILINES , *GRAPHENE oxide , *ELECTRIC capacity , *CARBON electrodes , *CYCLIC voltammetry - Abstract
Polyaniline (PANI) is a strong competitor as a high performance supercapacitor electrode material. However, it suffers from the poor cycling life, which is caused by electrode structure damages and materials degradation occurred during charge-discharge process. Therefore, self-healing PANI-graphene oxides based electrodes have been develop with the aim to enhance the electrode structure stability. It could rebuild the electronic contact between pulverized PANI nanostructures and electrode matrix, which leads to the recovery of specific capacitance. In coral-like PANI and PANI-graphene oxides (PANI-GO) composited based self-healing devices, capacitance retention of about 93% after 9000 cycles has been achieved. In order to further supress the material degradation, aniline tetramer-graphene oxides composites (AT-GO) with lower rigidity have been synthesized. The AT-GO based self-healing device exhibits a very good cycling stability with capacitance retention up to 97.5% after 9000 cycles. It also shows a high cell specific capacitance of 143.2 F g −1 obtained at 0.5 A g −1 , suggesting the good electrochemical performance. This work demonstrates the idea of using self-healing polymer to enhance the cycling stability of PANI composites based electrodes. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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35. Autonomous Self-healable Scratch-free Bilayer Anti-corrosion Film.
- Author
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Lee, Ji Min, Park, Junyong, Ko, Jongkuk, Shin, Yeji, Shin, Dongmin, Shim, Wonmi, Lee, Ju Hyun, Kappl, Michael, Lee, Junghoon, and Wooh, Sanghyuk
- Subjects
- *
POLYTEF , *METAL coating , *CHEMICAL stability , *METALLIC surfaces , *THIN films , *SELF-healing materials , *POLYMER films - Abstract
Scratch-free anti-corrosion bilayer film was designed with reversible Schiff-base linkage based autonomous self-healing matrix and thin hydrophobic outmost layer. [Display omitted] • Schiff-base linkages based polydimethylsiloxane (SC-PDMS) exhibits outstanding self-healing property. • The self-healable SC-PDMS layer with conformal contact allows scratch-free coating. • The polytetrafluoroethylene (PTFE) thin outermost layer improves chemical stability as well as hydrophobicity. • The PTFE/SC-PDMS bilayer coating exhibits a long-term anti-corrosion characteristic for metals. Thin hydrophobic polymer film, which physically prevents an approach of corrosive media, has been widely used as an anti-corrosion coating for metals. Though polymer film effectively passivates surface of metal, it loses its anti-corrosion property once the film is peeled off by physical damage, such as scratches. Corrosion can be propagated from the exposed area even if the area is small. Therefore, for long-term anti-corrosion, the film should be seamless and completely cover the entire metal surface without scratches. In this study, we introduce an autonomously self-healable hydrophobic coating with superior anti-corrosion property by a combination of self-healable/fluorinated polymers. Schiff-base linkages based polydimethylsiloxane (SC-PDMS) is used as a primary protection layer against corrosive media. The SC-PDMS matrix with the dynamic imine bonds allows scratch-free metal protection layer by reproducible damage healing property. In addition, we applied polytetrafluoroethylene (PTFE) thin film at the surface of the SC-PDMS, which suppresses the reaction of imine bond with water and helps to maintain long-term anti-corrosion property. Eventually, this simple coating of bilayer structure with SC-PDMS and PTFE shows an effective scratch-free corrosive resistance, providing a new way of long-term use of metals. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
36. Selection of healing agents for a vascular self-healing application.
- Author
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Cuvellier, A., Torre-Muruzabal, A., Van Assche, G., De Clerck, K., and Rahier, H.
- Subjects
- *
THERMOSETTING polymers , *VISCOSITY , *MECHANICAL behavior of materials , *GLASS transition temperature , *DIFFUSION , *ADHESION - Abstract
To increase the durability and reliability of thermosets, self-healing via a vascular network, is developed. A judicious choice of healing agents proves to be necessary to achieve the best recovery of properties. Four low viscosity two-component epoxy-amine healing systems were compared, to check which glass transition temperature range would be best to recover mechanical properties (T g ranging from −8 to 68 °C). Interdiffusion experiments show that all systems react sufficiently slowly at room temperature to allow interdiffusion of epoxy and amine over more than 1 mm before the diffusion is stopped by vitrification. Swelling tests revealed that most of the selected healing agents diffuse into the surrounding matrix and swell it. This might be beneficial for crack closure and improved adhesion between healing system and matrix. Flexural tests demonstrated that, the higher the glass transition temperature of the fully cured healing system, the higher the healing capability. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
37. Contributions of hard and soft blocks in the self-healing of metal-ligand-containing block copolymers.
- Author
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Bose, Ranjita K., Enke, Marcel, Grande, Antonio M., Zechel, Stefan, Schacher, Felix H., Hager, Martin D., Garcia, Santiago J., Schubert, Ulrich S., and van der Zwaag, Sybrand
- Subjects
- *
SELF-healing materials , *BLOCK copolymers , *CHAIN transfer (Chemistry) , *MANGANESE chlorides , *HOMOPOLYMERIZATIONS , *NICKEL nitrate , *SUPRAMOLECULAR chemistry - Abstract
The main aim of this work is to study the respective contribution of the hard and soft blocks of a metal-ligand containing block copolymer to the self-healing behavior. To this aim, different block copolymers containing terpyridine were synthesized using reversible addition-fragmentation chain transfer (RAFT) polymerization. These block copolymers consisted of polystyrene as the hard block, n -butyl acrylate (BA) as soft block and terpyridine units as the ligand moiety placed at different locations in the soft block. These block copolymers were complexed with manganese(II) chloride to introduce transient crosslinks and, thus, self-healing behavior. Homopolymers with the hard and soft block only were also synthesized and tested. A quasi-irreversible crosslinking, i.e. by using nickel(II) nitrate, was performed in order to study the dynamics of the permanently (strongly) crosslinked network. Rheological master curves were generated enabling the determination of the terminal flow in these networks and the reversibility of the supramolecular interactions. Additionally, the macroscopic scratch healing behavior and the molecular mobility of the polymer chains in these supramolecular networks were investigated. A kinetic study of the scratch healing was performed to determine the similarities in temperature dependence for rheological relaxations and macroscopic scratch healing. In our previous work, we have explored the effect of strength of the reversible metal-ligand interaction and the effect of changing the ratio of hard to soft block. This work goes further in separating the individual contributions of the hard and soft blocks as well as the reversible interactions and to reveal their relative importance in the complex phenomenon of scratch healing. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
38. Investigation on the Dynamic Mechanical Properties of Self-Healing Glass Fibre Reinforced Plastics.
- Author
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Mercy, J. Lilly and Prakash, S.
- Subjects
- *
SELF-healing materials , *SMART materials , *MECHANICAL properties of polymers , *GLASS fibers , *GLASS-reinforced plastics - Abstract
Self-healing polymeric materials developed in the last decade is one of the marvels in the field of material science and polymer chemistry. Self-healing Glass Fibre Reinforced Plastics (GFRP) was fabricated with the microcapsule based self-healing system which can be triggered by the catalyst, when the capsule breaks open releasing the healing agent, during crack formation. The dynamic mechanical properties of the composite were assessed to find its dependence on temperature, stress and frequency and to report the changes in stiffness and damping. The storage modulus, loss modulus and damping factor were investigated for various frequencies and temperature and discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
39. A high-performance self-healing polymer binder for Si anodes based on dynamic carbon radicals in cross-linked poly(acrylic acid).
- Author
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Jang, Wonseok, Kim, Sangwook, Kang, Yumi, Yim, Taeeun, and Kim, Tae-Hyun
- Subjects
- *
SELF-healing materials , *RADICALS (Chemistry) , *CROSSLINKED polymers , *ANODES , *ACRYLIC acid , *LITHIUM-ion batteries , *ENERGY density - Abstract
[Display omitted] • Novel polymer binders based on dynamic radicals were developed for Si anode. • Poly(acrylic acid) was functionalized with diarylbibenzofuranone to form 3D network. • The crosslinked network structure showed a self-healing property. • Enhance mechanical and electrochemical properties were obtained. Silicon (Si), which exhibits high theoretical capacity, is a promising material for high energy density anode material in Lithium Ion Batteries (LIBs) because it is abundant in nature, inexpensive, and eco-friendly. However, Si has excessive volume expansion with charge and discharge cycles, resulting in reduced capacity reversibility and collapsing electrode structures. To overcome this limitation, polymer binders equipped with various functions have been used to improve the electrochemical performance of Si. The present study developed a self-healing cross-linked poly(acrylic acid) (PAA) binder for Si anodes functionalized with diarylbibenzofuranone (DABBF), which exhibits self-healing from reversible C-C bonding and the debonding of dynamic carbon radicals. When applied to Si anodes, the PAA-based binder functionalized with DABBF formed a three-dimensional network, stabilizing the Si structure and achieving improved adhesion and mechanical properties. Its self-healing performance enabled the Si anodes to exhibit stable capacity retention. In addition, the adhesion performance and mechanical properties of Si anodes were higher when DABBF-functionalized PAA was used as a binder. At a current density of 0.5 C, a high initial coulombic efficiency (ICE) of 77.89% was achieved, and after 500 cycles, the capacity remained high, 1774.45 mAh g−1. A novel cross-linked polymer binder with self-healing ability was successfully developed for the first time using dynamic carbon radicals, and its excellent electrochemical performance significantly improved the stability of Si anodes. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
40. A Healable Resistive Heater as a Stimuli-Providing System in Self healing robots
- Author
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Tabrizian, Seyedreza Kashef, Sahraeeazartamar, Fatemeh, Brancart, Joost, Roels, Ellen, Ferrentino, Pasquale, Legrand, Julie, Van Assche, Guy, Vanderborght, Bram, Terryn, Seppe, Kashef Tabrizian, Seyedreza, Applied Mechanics, Faculty of Engineering, Materials and Chemistry, and Physical Chemistry and Polymer Science
- Subjects
Control and Optimization ,Polymers and Plastics ,Mechanical Engineering ,Biomedical Engineering ,soft actuators ,Self-healing polymer ,Computer Science Applications ,Human-Computer Interaction ,Embedded heater ,Artificial Intelligence ,Control and Systems Engineering ,Computer Vision and Pattern Recognition ,Bending actuator ,healable robots - Abstract
Self-healing polymers can address the damage susceptibility in soft robotics. However, in most cases, their healing requires a heat stimulus, provided by an external device. This paper presents a self-healing soft actuator with an integrated healable flexible heater, functioning as the stimuli-providing system. The actuator is constructed out of thermoreversible elastomers that are crosslinked by the Diels-Alder (DA) reaction, which provides the healing ability. The heater is manufactured from a DA-based composite network filled with 20 wt% carbon black to provide electrically conductive properties for resistive Joule heating. The flexibility of the heater does not compromise the actuator performance upon integration and the self-healing properties of both heater and actuator allow for damage repair. This includes very large damages, as both heater and actuator can recover (near 100%) from being cut completely in two pieces, using Joule heating at 90 °C with a bias voltage of about 30 V. The embedded heater, avoids the need for external intervention in the healing process, and provides healing quality assessment and a healing on-demand mechanism, paving the way for an optimum healing solution of damage resilient soft robots that require heat as a healing stimulus.
- Published
- 2022
- Full Text
- View/download PDF
41. Vacuum-Assisted Self-Healing Amphiphilic Copolymer Membranes for Gas Separation.
- Author
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Hong YW, Laysandra L, Chiu YC, and Kang DY
- Abstract
Membrane gas separation provides a multitude of benefits over alternative separation techniques, especially in terms of energy efficiency and environmental sustainability. While polymeric membranes have been extensively investigated for gas separations, their self-healing capabilities have often been neglected. In this work, we have developed innovative self-healing amphiphilic copolymers by strategically incorporating three functional segments: n -butyl acrylate (BA), N -(hydroxymethyl)acrylamide (NMA), and methacrylic acid (MAA). Utilizing these three functional components, we have synthesized two distinct amphiphilic copolymers, namely, AP
NMA (PBAx - co -PNMAy ) and APMAA (PBAx - co -PMAAy ). These copolymers have been meticulously designed for gas separation applications. During the creation of these amphiphilic copolymers, BA and NMA segments were selected due to their vital role in the ease of tuning mechanical and self-healing properties. The functional groups (-OH and -NH) present on the NMA segment interact with CO2 through hydrogen bonding, thereby boosting CO2 /N2 separation and achieving superior selectivity. We assessed the self-healing potential of these amphiphilic copolymer membranes using two distinct strategies: conventional and vacuum-assisted self-healing. In the vacuum-assisted approach, a robust vacuum pump generates a suction force, leading to the formation of a cone-like shape in the membrane. This formation allows common fracture sites to adhere and trigger the self-healing process. As a result, APNMA maintains its high gas permeability and CO2 /N2 selectivity even after the vacuum-assisted self-healing operation. The ideal CO2 /N2 selectivity of the APNMA membrane aligns closely with the commercially available PEBAX-1657 membrane (17.54 vs 20.09). Notably, the gas selectivity of the APNMA membrane can be readily restored after damage, in contrast to the PEBAX-1657 membrane, which loses its selectivity upon damage.- Published
- 2023
- Full Text
- View/download PDF
42. A combined fracture mechanical – rheological study to separate the contributions of hydrogen bonds and disulphide linkages to the healing of poly(urea-urethane) networks.
- Author
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Grande, A.M., Bijleveld, J.C., Garcia, S.J., and van der Zwaag, S.
- Subjects
- *
RHEOLOGY , *POLYMERS , *FRACTURE mechanics , *HYDROGEN bonding , *SULFIDES , *POLYURETHANES , *POLYMER networks , *HEALING - Abstract
This work presents a detailed study into the rheological properties and fracture healing behaviour of two poly(urea-urethane) polymers containing (i) hydrogen bonds and (ii) hydrogen bonds and disulphide linkages. The experimental procedure here presented using the temperature and time superposition allowed for the identification of the contribution of each reversible bond type to the network behaviour (rheology) and healing (fracture). During the experimental data analysis it was found that the same shift factors required to construct the rheological master curves from separate isothermal small-amplitude oscillatory shear (SAOS) measurements at different temperatures could also be applied to obtain a master curve for the fracture healing data as a function of healing time and temperature. This work shows therefore the apparent direct relationship between rheological response and macroscopic fracture healing. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
43. Designing semiencapsulation based covalently self-healable poly(methyl methacrylate) composites by Atom Transfer Radical Polymerization.
- Author
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Saikia, Bhaskar Jyoti and Dolui, Swapan Kumar
- Subjects
- *
POLYMETHYLMETHACRYLATE , *POLYMERIZATION research , *SELF-healing materials , *MOLECULAR weights , *FRACTURE toughness - Abstract
ABSTRACT Self-healable poly(methyl methacrylate) (PMMA) composites were fabricated with embedded glycidyl methacrylate (GMA) encapsulated poly(melamine-formaldehyde) microcapsules. The matrix polymers were synthesized via Atom Transfer Radical Polymerization using two different initiators; one linear and another hexafunctional. As the so prepared polymer matrix retains living characteristics, it can initiate a healing reaction when the encapsulated monomer reaches the matrix due to formation or extension of a crack and thus healing the system covalently. The effect of number of initiating functionality on healing characteristic was studied using both linear and 6-armed star PMMA having same targeted molecular weight. Both the systems were able to restore 100% original fracture toughness after healing. However, the polymer matrix prepared by hexafunctional initiator restored the fracture toughness much faster than that of the linear polymer matrix. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 1842-1851 [ABSTRACT FROM AUTHOR]
- Published
- 2016
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44. Interfacial self-healing of nanocomposite hydrogels: Theory and experiment.
- Author
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Wang, Qiming, Gao, Zheming, and Yu, Kunhao
- Subjects
- *
INTERFACIAL bonding , *HYDROGELS , *COLLOIDAL gels , *POLYMER analysis , *ERROR functions - Abstract
Polymers with dynamic bonds are able to self-heal their fractured interfaces and restore the mechanical strengths. It is largely elusive how to analytically model this self-healing behavior to construct the mechanistic relationship between the self-healing properties (e.g., healed interfacial strength and equilibrium healing time) and the material compositions and healing conditions. Here, we take a self-healable nanocomposite hydrogel as an example to illustrate an interfacial self-healing theory for hydrogels with dynamic bonds. In the theory, we consider the free polymer chains diffuse across the interface and reform crosslinks to bridge the interface. We analytically reveal that the healed strengths of nanocomposite hydrogels increase with the healing time in an error-function-like form. The equilibrium self-healing time of the full-strength recovery decreases with the temperature and increases with the nanoparticle concentration. We further analytically reveal that the healed interfacial strength decreases with increasing delaying time before the healing process. The theoretical results quantitatively match with our experiments on nanosilica hydrogels, and also agree well with other researchers’ experiments on nanoclay hydrogels. We expect that this theory would open promising avenues for quantitative understanding of the self-healing mechanics of various polymers with dynamic bonds, and offer insights for designing high-performance self-healing polymers. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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45. Ultra-fast self-healable stretchable bio-based elastomer/graphene ink using fluid dynamics process for printed wearable sweat-monitoring sensor.
- Author
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Gyu Son, Seon, Jun Park, Hong, Kim, Seon-Mi, Jin Kim, Seo, Sik Kil, Min, Jeong, Jae-Min, Lee, Youngeun, Eom, Youngho, Yeon Hwang, Sung, Park, Jeyoung, and Gill Choi, Bong
- Subjects
- *
FLUID dynamics , *WEARABLE technology , *GRAPHENE , *CONDUCTIVE ink , *SELF-healing materials , *ELECTRIC conductivity - Abstract
• Preparation of self-healable, stretchable, and printable graphene ink based on a fluid dynamic process. • Demonstration of stretchable sweat sensor showing excellent electrochemical performances with high self-healing efficiency (99%). • Demonstration of self-healing ability in real-time monitoring on-body tests of wearable device. The practical application of wearable real-time monitoring systems is currently restricted by the irreversible mechanical damage and fracture of their sensors during physical activity, which has inspired the development of self-healable ink materials. However, progress in this field is limited by the difficulty of combining high mechanical strength with high conductivity and realizing scalable and efficient fabrication. Herein, a fluid dynamics process is used to prepare a self-healable, robust, and conductive ink through the incorporation of graphene into a self-healing polymer, namely poly(1,4-cyclohexanedimethanol succinate-co-citrate). The corresponding screen-printed serpentine-structured electrode exhibits spontaneous conductivity self-healing during 10 cut-heal cycles and at a tensile strain of 200% under ambient conditions. These unique properties are used to fabricate a highly stretchable electrochemical Na+ sensor with a high self-healing efficiency (average sensitivity retention of 99%). On-body tests reveal that this wearable sensor is well suited for the real-time monitoring of sweat during physical exercise and is capable of autonomous repair after mechanical cutting, showing a healing time of ∼12 s. Thus, our work paves the way to the commercialization of devices typically requiring a combination of mechanical resilience and stable electrical performance, e.g., e-skin, sweat sensors, soft robotics, and biofuel cells. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
46. A mechanically robust self-healing binder for silicon anode in lithium ion batteries
- Author
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Chen, Hao, Wu, Zhenzhen, Su, Zhong, Chen, Su, Yan, Cheng, Al-Mamun, Mohammad, Tang, Yongbing, Zhang, Shanqing, Chen, Hao, Wu, Zhenzhen, Su, Zhong, Chen, Su, Yan, Cheng, Al-Mamun, Mohammad, Tang, Yongbing, and Zhang, Shanqing
- Abstract
Both industrious and academic research societies have considered silicon (Si) as the most promising anode for next-generation lithium ion batteries (LIBs) because silicon offers more than one order of magnitude higher capacity than conventional anode materials. However, huge volume changes and pulverization of the silicon particles during the charge/discharge processes damage the longevity of Si-based LIBs. Self-healing binders could tackle this problem by in-situ repairing the damage to the silicon anode. Herein, we synthesized a novel self-healing poly(ether-thioureas) (SHPET) polymer with balanced rigidity and softness for the silicon anode. The as-prepared silicon anode with the self-healing binder exhibits excellent structural stability and superior electrochemical performance, delivering a high discharge capacity of 3744 mAh g−1 at a current density of 420 mA g−1, and achieving a stable cycle life with a high capacity retention of 85.6% after 250 cycles at a high current rate of 4200 mA g−1. The success of this work suggests that the proposed SHPET binder facilitates fast self-healing, buffers the drastic volume changes and overcomes the mechanical strain in the course of the charge/discharge process, and could subsequently accelerate the commercialization of the silicon anode.
- Published
- 2021
47. From Scratch Closure to Electrolyte Barrier Restoration in Self-Healing Polyurethane Coatings
- Author
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Montano, V. (author), Vogel, Wouter (author), Smits, Angela (author), van der Zwaag, S. (author), Garcia, Santiago J. (author), Montano, V. (author), Vogel, Wouter (author), Smits, Angela (author), van der Zwaag, S. (author), and Garcia, Santiago J. (author)
- Abstract
The effects of the soft block fraction and H-bond state in thermoplastic polyurethanes on autonomous entropy-driven scratch closure and barrier restoration are studied. To this aim, comparable polyurethanes with different segmentation states are applied as organic coatings on plain carbon steel plates, scratched under very well-controlled conditions, and the scratch closure and sealing kinetics are studied in detail. The scratch closure is measured optically, while the barrier restoration is probed by the accelerated cyclic electrochemical technique (ACET). Scratch closure, attributed to entropic elastic recovery (EER), is followed in a marked two-step process by barrier restoration governed by local viscous flow and the state of the interfacial hydrogen bonding. Polyurethanes with a lower soft phase fraction lead to a higher urea/urethane ratio, which in turn influences the healing efficiency of each healing step. Interestingly, softer polyurethanes leading to efficient crack closure were unable to sufficiently restore barrier properties. The present work highlights the critical role of the soft/hard block and urea/urethane H-bond state content on crack closure and barrier restoration of anticorrosive organic coatings and points at design rules for the design of more efficient corrosion-protective self-healing polyurethanes., Novel Aerospace Materials
- Published
- 2021
- Full Text
- View/download PDF
48. In-depth numerical analysis of the TDCB specimen for characterization of self-healing polymers.
- Author
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Garoz Gómez, David, Gilabert, Francisco A., Tsangouri, Eleni, Van Hemelrijck, Danny, Hillewaere, Xander K.D., Du Prez, Filip E., and Van Paepegem, Wim
- Subjects
- *
THERMOSETTING polymers , *CANTILEVERS , *SELF-healing materials , *NUMERICAL analysis , *FRACTURE toughness , *DISPERSION (Chemistry) , *FINITE element method - Abstract
The Tapered Double Cantilever Beam (TDCB) is the common specimen to study self-healing thermosetting polymers. While this geometry allows characterising the mode I fracture toughness without taking into account the crack length, the experiments show an important dispersion and unstable behaviour that must be taken into account to obtain accurate results. In this paper, finite element simulations have been used to understand the experimental behaviour. Static simulations with a stationary crack give the local stresses and the stress intensity factors at the crack tip when the TDCB is under load. In addition, the eXtended Finite Element Method (XFEM) has been used to make quasi-static crack propagation simulations. The results indicate that the crack tip has a curved profile during the propagation, advancing more at the edges than at the centre. The crack propagation begins when the applied load reaches a critical value. The unstable crack propagation noted in the experiments can be reproduced by introducing an unstable behaviour in the simulations. Finally, the sensitivity of the critical load has been studied as a function of the friction between pin and hole, tolerance of geometrical dimensions, and cracks out of the symmetric plane. The results can partially explain the dispersion of the experimental data. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
49. From Scratch Closure to Electrolyte Barrier Restoration in Self-Healing Polyurethane Coatings
- Author
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Vincenzo Montano, Sybrand van der Zwaag, Angela Smits, Santiago J. Garcia, and Wouter Vogel
- Subjects
Thermoplastic ,Materials science ,Polymers and Plastics ,Carbon steel ,self-healing polymer ,Electrolyte ,urea ,engineering.material ,Article ,chemistry.chemical_compound ,Crack closure ,polymer architecture ,Composite material ,Self-healing material ,Polyurethane ,computer.programming_language ,chemistry.chemical_classification ,Process Chemistry and Technology ,Organic Chemistry ,ACET ,self-healing coating ,chemistry ,Scratch ,polyurethane ,Self-healing ,engineering ,computer - Abstract
The effects of the soft block fraction and H-bond state in thermoplastic polyurethanes on autonomous entropy-driven scratch closure and barrier restoration are studied. To this aim, comparable polyurethanes with different segmentation states are applied as organic coatings on plain carbon steel plates, scratched under very well-controlled conditions, and the scratch closure and sealing kinetics are studied in detail. The scratch closure is measured optically, while the barrier restoration is probed by the accelerated cyclic electrochemical technique (ACET). Scratch closure, attributed to entropic elastic recovery (EER), is followed in a marked two-step process by barrier restoration governed by local viscous flow and the state of the interfacial hydrogen bonding. Polyurethanes with a lower soft phase fraction lead to a higher urea/urethane ratio, which in turn influences the healing efficiency of each healing step. Interestingly, softer polyurethanes leading to efficient crack closure were unable to sufficiently restore barrier properties. The present work highlights the critical role of the soft/hard block and urea/urethane H-bond state content on crack closure and barrier restoration of anticorrosive organic coatings and points at design rules for the design of more efficient corrosion-protective self-healing polyurethanes.
- Published
- 2021
50. Effect of the plasticizer on the self-healing properties of a polymer coating based on the thermoreversible Diels–Alder reaction.
- Author
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Postiglione, Giovanni, Turri, Stefano, and Levi, Marinella
- Subjects
- *
PLASTICIZERS , *SELF-healing materials , *DIELS-Alder reaction , *PLASTIC coating , *FOURIER transform infrared spectroscopy , *BENZYL alcohol , *TENSILE strength - Abstract
A self-healing polymer for coating application was developed based on thermoreversible Diels–Alder (DA) reactions. The polymer network is formed by reacting a mixture of trifunctional and difunctional furanized resins (3F and 2F) with a bismaleimide (2M). The DA reaction occurs at temperature above 50 °C whilst retro-DA reaction occurs at about 120 °C. FTIR spectra were taken in order to monitor the reaction progress, and the thermal reversibility of the reaction was proved by DSC and DMA tests. A significant improvement of both the mechanical properties and the self-healing behaviour was achieved by introduction of small amount of a suitable plasticizer like benzyl alcohol. Self-healing properties of the plasticized polymer resulted in complete scratch recovery after retro-DA and DA reaction, whilst tensile testing reveals a 48% restoring of the pristine mechanical strength. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
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