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The potential of three‐dimensional (3D) printing technology in the fabrication of advanced polymer composites is becoming increasingly evident. This review discusses the latest research developments and applications of 3D printing in polymer composites. First, it focuses on the optimization of 3D printing technology, that is, by upgrading the equipment or components or adjusting the printing parameters, to make them more adaptable to the processing characteristics of polymer composites and to improve the comprehensive performance of the products. Second, it focuses on the 3D printable novel consumables for polymer composites, which mainly include the new printing filaments, printing inks, photosensitive resins, and printing powders, introducing the unique properties of the new consumables and different ways to apply them to 3D printing. Finally, the applications of 3D printing technology in the preparation of functional polymer composites (such as thermal conductivity, electromagnetic interference shielding, biomedicine, self‐healing, and environmental responsiveness) are explored, with a focus on the distribution of the functional fillers and the influence of the topological shapes on the properties and functional characteristics of the 3D printed products. The aim of this review is to deepen the understanding of the convergence between 3D printing technology and polymer composites and to anticipate future trends and applications. [ABSTRACT FROM AUTHOR]

The trends of miniaturization, lightweight, and high integration in electronics have brought serious issues in heat dissipation and electromagnetic compatibility and also limited the simultaneous use of thermally conductive and microwave absorption materials. Therefore, it is imperative to design materials that possess those dual functions. In this work, one‐pot method is used to anchor zeolitic imidazolate framework ZIF‐67 coated with polydopamine (PDA) on boron nitride (BN) to obtain BN@ZIF‐67@PDA. The pyrolysis product BN@Co‐C@C is used as heterostructured thermally conductive/microwave absorption fillers and blended with polyethylene terephthalate (PET) to prepare BN@Co‐C@C/PET composites. When the mass ratio of BN to ZIF‐67@PDA is 7.5:1 and the mass fraction of BN7.5@Co‐C@C is 45 wt%, the BN7.5@Co‐C@C/PET composites exhibit excellent thermal conductivities and microwave absorption performances. The thermal conductivity coefficient is 5.37 W m−1 K−1, which is 35.8 times higher than that of PET (0.15 W m−1 K−1), and also higher than that of 45 wt% (BN7.5/Co‐C@C)/PET composites (4.03 W m−1 K−1) prepared by directly mixing. The minimum reflection loss of 45 wt% BN7.5@Co‐C@C/PET composites are −63.1 dB at 4.72 GHz, and the corresponding effective absorption bandwidth is 1.28 GHz (4.08–5.36 GHz), achieving excellent microwave absorption performance at C band. [ABSTRACT FROM AUTHOR]

The development of highly thermally conductive composites that combine visible light/infrared camouflage and information encryption has been endowed with great significance in facilitating the application of 5G communication technology in military fields. This work uses aramid nanofibers (ANF) as the matrix, hetero‐structured silver nanowires@boron nitride nanosheets (AgNWs@BNNS) prepared by in situ growth as fillers, which are combined to fabricate sandwich structured thermally conductive and electrically insulating (BNNS/ANF)‐(AgNWs@BNNS)‐(BNNS/ANF) (denoted as BAB) composite films by "filtration self‐assembly, air spraying, and hot‐pressing" method. When the mass ratio of AgNWs@BNNS to BNNS is 1 : 1 and the total mass fraction is 50 wt %, BAB composite film has the maximum in‐plane thermal conductivity coefficient (λ∥ of 10.36 W/(m ⋅ K)), excellent electrical insulation (breakdown strength and volume resistivity of 41.5 kV/mm and 1.21×1015 Ω ⋅ cm, respectively) and mechanical properties (tensile strength of 170.9 MPa). 50 wt % BAB composite film could efficiently reduce the equilibrium temperature of the central processing unit (CPU) working at full power, resulting in 7.0 °C lower than that of the CPU solely integrated with ANF directly. In addition, BAB composite film boasts adaptive visible light/infrared dual camouflage properties on cement roads and jungle environments, as well as the function of fast encryption of QR code information within 24 seconds. [ABSTRACT FROM AUTHOR]

Epoxy resins with a high dielectric constant and low intrinsic thermal conductivity coefficient cannot meet the current application requirements of advanced electronic and electrical equipment. Therefore, novel fluorine‐containing liquid crystal epoxy compounds (TFSAEy) with fluorinated groups, biphenyl units, and flexible alkyl chains are first synthesized via amidation and esterification reactions. Then, 4,4′‐diaminodiphenylmethane (DDM) is used as a curing agent to prepare the corresponding fluorine‐containing liquid crystal epoxy resins. The obtained dielectric constant (ε) and dielectric loss (tan δ) values of TFSAEy/DDM at 1 MHz are 2.54 and 0.025, respectively, which are significantly lower than those of conventional epoxy resins (E‐51/DDM, 3.52 and 0.038). Additionally, the intrinsic thermal conductivity coefficient (λ) of TFSAEy/DDM is 0.36 W/(m·K), 71.4% higher than that of E‐51/DDM (0.21 W/(m·K)). Meanwhile, the corresponding elastic modulus, hardness, glass transition temperature, and heat resistance index of TFSAEy/DDM are 5.73 GPa, 0.35 GPa, 213.5°C, and 188.7°C, respectively, all superior to those of E‐51/DDM (3.68 GPa, 0.27 GPa, 107.2°C, and 174.8°C), presenting potential application in high‐heating electronic component packaging and printed circuit boards. [ABSTRACT FROM AUTHOR]

Transition metal carbides/nitrides/carbonitrides (MXenes) exhibit tremendous potential for optical applications due to their diverse elemental composition and adaptable structural properties. Based on introducing the preparation methods and optical properties of MXenes, this review focuses on the latest advances in MXenes‐based optical functional materials, and analyzes the performance enhancement mechanisms of MXenes‐based optical functional materials for photothermal conversion and photocatalysis. The key scientific and technical bottlenecks in the field of MXenes‐based optical functional materials are pointed out, and the future development trends and research directions of MXenes‐based optical functional materials are prospected. [ABSTRACT FROM AUTHOR]

Stealth technology is used to enhance the survival of military equipment in the field of military surveillance, as it utilizes a combination of techniques to render itself undetectable by enemy radar systems. Radar absorbing materials (RAMs) are specialized materials used to reduce the reflection (or absorption) of radar signals to provide stealth capability, which is a core component of passive countermeasures in military applications. The properties of RAMs can be optimized by adjusting their composition, microstructure, and surface geometry. Carbon‐based materials present a promising approach for the fabrication of ultrathin, versatile, and high‐performance RAMs due to their large specific surface area, lightweight, excellent dielectric properties, high electrical conductivity, and stability under harsh conditions. This review begins with a brief history of stealth technology and an introduction to electromagnetic waves, radar systems, and radar absorbing materials. This is followed by a discussion of recent research progress in carbon‐based RAMs, including carbon blacks, carbon fibers, carbon nanotubes, graphite, graphene, and MXene, along with an in‐depth examination of the principles and strategies on electromagnetic attenuation characteristics. Hope this review will offer fresh perspectives on the design and fabrication of carbon‐based RAMs, thereby fostering a deeper fundamental understanding and promoting practical applications. [ABSTRACT FROM AUTHOR]

The positive liquid crystals, 4′‐heptyl‐4‐biphenylcarbonitrile (7CB), are used to functionalize carbon nanotubes (LC‐CNT), which can be aligned in the liquid crystalline polyimide (LC‐PI) matrix under an alternating electric field to fabricate the thermally conductive LC‐CNT/LC‐PI composite films. The efficient establishment of thermal conduction pathways in thermally conductive LC‐CNT/LC‐PI composite films with a low amount of LC‐CNT is achieved through the oriented alignment of LC‐CNT within the LC‐PI matrix. When the mass fraction of LC‐CNT is 15 wt %, the in‐plane thermal conductivity coefficient (λ∥) and the through‐plane thermal conductivity coefficient (λ⊥) of the LC‐CNT/LC‐PI composite films reach 4.02 W/(m ⋅ K) and 0.55 W/(m⋅K), which are 90.5 % and 71.9 % higher than those of the intrinsically thermally conductive LC‐PI films respectively, also 28.8 % and 5.8 % higher than those of the CNT/LC‐PI composite films respectively. Meanwhile, the thermally conductive LC‐CNT/LC‐PI composite films also possess excellent mechanical and heat resistance properties. The Young's modulus and the heat resistance index are 2.3 GPa and 297.7 °C, respectively, which are higher than the intrinsically thermally conductive LC‐PI films and the thermally conductive CNT/LC‐PI composite films under the same amount of CNT. [ABSTRACT FROM AUTHOR]

Paclitaxel (PTX) resistance is a key cause of chemotherapy failure in patients with triple negative breast cancer (TNBC). The aim of this study is to investigate the effect and mechanism of long non‐coding RNA (lncRNA) on the PTX resistance of TNBC cells through autophagy. MDA‐MB‐231 cells are used to induce the PTX‐resistant TNBC cell line MDA‐MB‐231.PR (MDR) by increasing dose intermittently. Quantitative real‐time polymerase chain reaction (qRT‐PCR) was used to validate the mRNA levels of phosphoinositide‐3‐kinase class 3 (PIK3C3), miR‐361‐5p and lncRNA PRKCQ‐AS1 in the cells, and Western blot analysis was used to detect the protein expressions of PIK3C3, autophagy‐related, drug‐resistant and apoptosis‐related genes. MDC staining detected the formation of autophagic vacuoles. The interactions between miR‐361‐5p and PIK3C3 and between lncRNA PRKCQ‐AS1 and miR‐361‐5p were verified by dual‐luciferase assay. Cell viability, apoptosis, migration and invasion were assessed by performing MTT, flow cytometry assay, and transwell assay. The mRNA level of miR‐361‐5p and the autophagy and drug resistance levels of TNBC PTX‐resistant cells were significantly up‐regulated. miR‐361‐5p could target autophagy‐related gene PIK3C3, and overexpression of miR‐361‐5p could down‐regulate PIK3C3 protein expression and autophagy level and PTX resistance of MDR cells. LncRNA PRKCQ‐AS1 was selected through bioanalysis, and miR‐361‐5p could target lncRNA PRKCQ‐AS1. In addition, lncRNA PRKCQ‐AS1 level was up‐regulated in TNBC PTX‐resistant cells, and knockdown of lncRNA PRKCQ‐AS1 could weaken autophagy and drug resistance level and could promote cell apoptosis. Overexpression of lncRNA PRKCQ‐AS1 reversed the pro‐apoptotic effect and down‐regulation of autophagy and resistance levels was induced by miR‐361‐5p. In vivo experiments were performed to verify the role of lncRNA PRKCQ‐AS1. We demonstrate that down‐regulation of lncRNA PRKCQ‐AS1 weakened PTX resistance and promoted cell apoptosis by miR‐361‐5p/PIK3C3 mediated autophagy. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Branched fluorine/adamantane PBO precursor (preFABPBO), synthesized via random co‐condensation between 2,2‐bis(3‐amino‐ 4‐hydroxyphenyl)hexafluoro propane, 1,3‐adamantanedicarbonyl dichloride, and trimesoyl chloride, is performed as interfacial compatibilizer, bisphenol A dicyanate ester (BADCy) resin as polymer matrix, and poly(p‐phenylene‐2,6‐benzobisoxazole) (PBO) fibers as reinforcements to prepare PBO fibers/FABPBO‐BADCy wave‐transparent laminated composites by high temperature molding. The mechanical properties, wave‐transparent performances, and heat resistances of PBO fibers/BADCy composites are simultaneously improved by the addition of preFABPBO. The interlaminar shear strength (ILSS) and flexural strength of PBO fibers/FABPBO‐BADCy composites are 48.9 and 665.3 MPa, respectively, increased by 33.2% and 13.3% compared to those of PBO fibers/BADCy composites (36.7 and 587.4 MPa). The dielectric constant and dielectric loss values at 106 Hz are 2.53 and 0.003, respectively, lower than those of PBO fibers/BADCy composites (3.06 and 0.006), and the corresponding wave transmission efficiency is 94.8%, which also presents excellent stability over the wide temperature (25—200 °C) and frequency range (103—107 Hz and 8.2—12.4 GHz). Meanwhile, the heat resistance index and glass transition temperature are 229.9 °C and 247.5 °C, also better than those of PBO fibers/BADCy composites (229.6 °C and 247.1 °C). [ABSTRACT FROM AUTHOR]

Thermal conduction for electronic equipment has grown in importance in light of the burgeoning of 5G communication. It is imperatively desired to design highly thermally conductive fillers and polymer composite films with prominent Joule heating characteristics and extensive mechanical properties. In this work, "solvothermal & in situ growth" method is carried out to prepare "Fungal tree"‐like hetero‐structured silver nanowires@boron nitride nanosheet (AgNWs@BNNS) thermally conductive fillers. The thermally conductive AgNWs@BNNS/ANF composite films are obtained by the method of "suction filtration self‐assembly and hot‐pressing". When the mass fraction of AgNWs@BNNS is 50 wt%, AgNWs@BNNS/ANF composite film presents the optimal thermal conductivity coefficient of 9.44 W/(m ⋅ K) and excellent tensile strength of 136.6 MPa, good temperature‐voltage response characteristics, superior electrical stability and reliability, which promise a wide application potential in 5G electronic devices. [ABSTRACT FROM AUTHOR]

Inspired by shape‐morphing organisms in nature, researchers have developed various hydrogels with stimuli‐responsive swelling, shrinking, bending, folding, origami, rolling, twisting, or locomotion. These smart hydrogels are usually created by patterning or 4D printing. The shape morphing of hydrogels allows the fabrication of helixing, twisting, and rolling microstructures, all of which are hard to reproduce directly by ordinary techniques. More importantly, under external stimuli (e.g., solvent, humidity, temperature, light, pH, and electric/magnetic fields), many hydrogels exhibit recoverable shape morphing and thus find promising applications in grippers, sensors, valves, soft robotics, etc. Since shape morphing determines the functions of hydrogels in a great number of cases, herein, recent advances of stimuli‐responsive hydrogels are summarized, with their types, shape‐morphing mechanisms, fabrication methods, shape‐morphing modes, and extensive applications covered. The conclusion and perspectives are also presented to guide the design and fabrication of functional hydrogels. [ABSTRACT FROM AUTHOR]

Multifunctional wearable electronic devices based on natural materials are highly desirable for versatile applications of energy conversion, electronic skin and artificial intelligence. Herein, multifunctional wearable silver nanowire decorated leather (AgNW/leather) nanocomposites with hierarchical structures for integrated visual Joule heating, electromagnetic interference (EMI) shielding and piezoresistive sensing are fabricated via the facile vacuum‐assisted filtration process. The AgNWs penetrate the micro‐nanoporous structures in the corium side of leather constructing highly‐efficient conductive networks. The resultant flexible and mechanically strong AgNW/leather nanocomposites exhibit extremely low sheet resistance of 0.8 Ω/sq, superior visual Joule heating temperatures up to 108 °C at low supplied voltage of 2.0 V due to efficient energy conversion, excellent EMI shielding effectiveness (EMI SE) of ≈55 dB and outstanding piezoresistive sensing ability in human motion detection. This work demonstrates the fabrication of multifunctional AgNW/leather nanocomposites for next‐generation wearable electronic devices in energy conversion, electronic skin and artificial intelligence, etc. [ABSTRACT FROM AUTHOR]

Electromagnetic interference (EMI) shielding materials with excellent flexibility and mechanical properties and outstanding thermal conductivity have become a hot topic of research in functional composites. In this study, the "sol–gel‐film conversion technique" is used to assemble polyetherimide‐functionalized Ti3C2Tx nanosheets (f‐Ti3C2Tx) with poly(p‐phenylene‐2,6‐benzobisoxazole) (PBO) nanofibers (PNFs), followed by dialysis and vacuum drying to prepare f‐Ti3C2Tx/PNF films with lamellar structures. When the loading of f‐Ti3C2Tx is 70 wt%, the f‐Ti3C2Tx/PNF film presents optimal comprehensive properties, with an EMI shielding effectiveness (SE) of 35 dB and a specific SE/thickness ((SSE, SE/density)/t) of 8211 dB cm2/g, a tensile strength of 125.1 MPa, an in‐plane thermal conductivity coefficient (λ) of 5.82 W/(m K), and electrical conductivity of 1943 S/m. After repeated folding for 10,000 cycles, the EMI SE and the tensile strength of f‐Ti3C2Tx/PNFs films still remain 33.4 dB and 116.1 MPa, respectively. Additionally, the f‐Ti3C2Tx/PNF film also shows excellent thermal stability, flame retardancy, and structural stability. This would provide a novel method for the design and fabrication of multifunctional composite films and considerably expand the applications of MXene‐ and PNF‐based composites in the fields of EMI shielding and thermal management. [ABSTRACT FROM AUTHOR]

The integration of intrinsic thermal conductivity and intrinsic flame retardancy of epoxy resins shows wider application prospects in electricals and electronics. Discotic liquid crystal epoxy (D‐LCE) is synthesized from pyrocatechol, 2‐allyloxyethanol, and 3‐chloroperoxybenzoic acid. P/Si synergistic flame‐retardant co‐curing agent (DOPO‐POSS, DP) is synthesized from p‐hydroxybenzaldehyde, 9, 10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene 10‐oxide (DOPO), and amino terminated polysilsesquioxane (POSS). Finally, D‐LCE is cured within liquid crystal range with 4, 4′‐diaminodiphenyl methane (DDM) and DP, to obtain intrinsic highly thermal conductive/flame‐retardant epoxy resins (D‐LCERDP). D‐LCERDP‐10.0 (10.0 wt% DP) synchronously possesses excellent intrinsic thermal conductivity and intrinsic flame retardancy, with thermal conductivity coefficient in vertical and parallel direction (λ⊥ and λ∥) of 0.34 and 1.30 W m−1 K−1, much higher than that of general bisphenol A epoxy resin (E‐51, λ⊥ of 0.19 W m−1 K−1, λ∥ of 0.65 W m−1 K−1). The limiting oxygen index (LOI) value of D‐LCERDP‐10.0 reaches 31.1, also better than those of E‐51 (19.8) and D‐LCER (21.3). [ABSTRACT FROM AUTHOR]

The thermal conductivity of bulk polymers is usually very low, which is due to the amorphous domains where chains are randomly entangled, improving the degree of the chain alignment and forming a continuous thermal conduction network are expected to enhance the thermal conductivity. A series of liquid crystalline monomer‐poly (vinyl alcohol) dispersion (MDLC) films with high thermal conductivity containing microscopic‐ordered structure were prepared by introducing a highly ordered liquid crystalline monomer (LCM) exhibiting Smectic phase. The thermal conductivity of MDLC films was strongly related to the amount of LCM, which firstly increased and then decreased with the increase of LCM content. The thermal conductivity of MDLC film reached up to 1.20 W m−1 K−1 when the content of LCM was 15 wt% and rapidly decreased to 0.85 W m−1 K−1 as the content of LCM further increased to 25 wt%. LCM with low content (1–15 wt%) showed good fluidity, dispersity and interfacial compatibility in PVA molecular chains, which further increases the regularity of molecular chains alignment. [ABSTRACT FROM AUTHOR]

Major disadvantages of black phosphorus (BP) are its poor air‐stability and poor solubility in common organic solvents. The best way to solve this problem is to incorporate BP into a polymer backbone or a polymer matrix to form novel functional materials that can provide both challenges and opportunities for new innovation in optoelectronic and photonic applications. As a proof‐of concept application, we synthesized in situ the first highly soluble conjugated polymer‐covalently functionalized BP derivative (PDDF‐g‐BP) which was used to fabricate a resistive random access memory (RRAM) device with a configuration of Au/PDDF‐g‐BP/ITO. In contrast to PDDF without memory effect, PDDF‐g‐BP‐based device exhibits a nonvolatile rewritable memory performance, with a turn‐on and turn‐off voltages of +1.95 V and −2.34 V, and an ON/OFF current ratio of 104. The current through the device in both the ON and OFF states is still kept unchanged even at 200th switching cycle. The PDDF/BP blends show a very unstable memory performance with a very small ON/OFF current ratio. [ABSTRACT FROM AUTHOR]

Three different dopants are used to fabricate electrospun dopants/polystyrene (dopants/PS) composite fibers from PS solution and PS sol. The relative humidity and the influence of the dopants on the morphologies, diameter, porous structures, and dopant distribution of electrospun PS fibers are investigated. Compared to those obtained from PS solution, electrospun dopants/PS composite fibers from PS sol with hollow-porous and multichannel hollow-porous structures present significant advantages due to the multi-stage degree of interfacial structure and diversity of the internal environment. In comparison to coaxial electrospun PS fibers, the electrospun dopants/PS composite fibers from PS sol obtained in one step have an improved yield and a simplified technological process simultaneously, leading to significant competitiveness in fields such as catalysis, fluidics gas storage, and sensing. [ABSTRACT FROM AUTHOR]

Quartz fibers (QFs) and two polyhedral oligomeric silsesquioxane (POSS) (epoxy-POSS and hydroxy-POSS) are performed to regulate the dielectric properties, heat resistance, and mechanical properties of cyanate ester (CE) resins. With the introduction of POSS, the dielectric constant and dielectric loss tangent values of the POSS/QFs/CE laminated composites are decreased obviously. The heat resistance properties and flexural strength values of the laminated composites are increased, but the interlaminar shear strength values of the laminated composites are decreased slightly. The EP-POSS/QFs/CE laminated composites have relatively better dielectric, heat resistance, and mechanical properties than those of HO-POSS/QFs/CE laminated composites. POLYM. COMPOS., 36:2017-2021, 2015. © 2014 Society of Plastics Engineer [ABSTRACT FROM AUTHOR]

ABSTRACT A series of highly soluble aromatic polyimides with excellent thermal properties were fabricated by traditional two-step polycondensation reaction of dianhydride monomer 4,4′-(4,4′-isopropylidenediphenoxy)bis(phthalic anhydride) or 4,4-(hexafluoroisopropylidene)diphthalic anhydride with diamine monomer 1,3-bis(4-aminophenoxy)benzene or 1,3-bis(3-aminopropyl) tetramethyldisiloxane in N,N-dimethylacetylamide solvent. Results revealed that copolyimide of PI-4 containing trifluoromethyl and tetramethyldisiloxane possessed excellent solubility and remarkable thermal properties. PI-4 could dissolve well in common low boiling point solvents such as THF of up to 80 mg/mL and acetone of 40 mg/mL. Moreover, the 10% weight loss temperature of the PI-4 was 539°C and the Tg value of the PI-4 was 311°C. PI-4 might be easily cast into flexible and tough films applied in optoelectronic devices. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41713. [ABSTRACT FROM AUTHOR]

NaCl-added mesoporous silica SBA-15 was prepared by a simple grind method which needs low energy cost. Humidity sensing property was studied. Study results indicated that Na Cl-added material possesses higher humidity sensitivity. Its impedance changed more than four orders of magnitude when the relative humidity changed from 11% RH to 95% RH. From the viewpoint of economy, Na Cl-added SBA-15 material which possesses high sensitivity and needs low energy cost is more suitable to be a promising humidity sensing material. Complex impedance spectra, the corresponding equivalent circuit, and bode diagrams were carefully analyzed to explore sensing mechanism. [ABSTRACT FROM AUTHOR]

The volume fraction of functionalized graphene nanoplatelets (GNPs) influencing on the thermal conductivities of GNPs/polyphenylene sulfide (GNPs/PPS) composites are investigated. Results reveal that a great improvement of the thermal conductivities with the addition of functionalized GNPs, and the thermal conductivity of the GNPs/PPS composite is 4.414 W/mK with 29.3 vol% functionalized GNPs, 19 times higher than that of the pure PPS matrix. The significantly high improvement of the thermal conductivities is ascribed to good thermal transmission through GNPs networks in the PPS matrix, following a thermal percolation behavior. Meantime, the GNPs have strong ability to generate continuous thermally conductive chains, and the formation of thermally conductive networks becomes much easier. POLYM. COMPOS., 35:1087-1092, 2014. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A novel 'three-step approach' of methanesulfonic acid/γ-aminopropyl triethoxy silane/GlycidylEthyl polyhedral oligomeric silsesquioxane (MSA/KH550/POSS) was proposed to functionalize the surface of high modulus poly ( p-phenylene-2,6-benzobisoxazole) (HMPBO) fibers. Results indicated that GlycidylEthyl POSS was successfully grafted on the surface of HMPBO fibers and the surface roughness of HMPBO fibers was increased obviously. The single fiber pull-out strength of POSS- g-HMPBO/epoxy resin microcomposite was improved to 1.19 MPa, better than that of native HMPBO/epoxy resin microcomposite. POLYM. COMPOS., 35:611-616, 2014. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Grafting polymerization of vinyltriethoxysilane (VTES) onto styrene-butadiene rubber (SBR) was firstly carried out in latex, using potassium persulfate (KPS) as initiator. The grafted SBR was further reinforced with silica produced by sol-gel reaction of tetraethoxysilane (TEOS). The grafted of VTES onto SBR was characterized and confirmed by ATR-FTIR and 1H-NMR. Results revealed that the addition of VTES could considerably improve the content of silica, bound rubber in SBR and utilized efficiency of TEOS. Meanwhile, the curing characteristics and mechanical properties of the vulcanized in situ reinforced SBR- g-VTES were also investigated and compared with that of the silica-reinforced SBR prepared by mechanical mixing. The delta torque, tensile, and tear strength of in situ reinforced SBR- g-VTES were higher than that of silica-reinforced SBR. Dynamic mechanical analysis showed that the interaction between silica and SBR of in situ reinforced SBR- g-VTES was also better than that of the silica-reinforced SBR. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013 [ABSTRACT FROM AUTHOR]

Magnetic polyimide hybrid thin films were synthesized from pyromellitic dianhydride (PMDA), 4,4′-oxydianiline (ODA), and Fe3O4 magnetic nanoparticles via thermal imidiazation in nitrogen environments. The magnetic polyimide hybrid thin films were analyzed and characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The magnetic properties of magnetic nanoparticles and polymer hybrid thin films were assessed using a vibrating sample magnetometer (VSM), and the physical properties of hybrid thin films were tested. Results revealed that the magnetic polyimide hybrid thin films had superparamagnetic behavior and excellent mechanical properties. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Boron nitride (BN) micro particles modified by silane coupling agent, γ-aminopropyl triethoxy silane (KH550), are employed to prepare BN/epoxy resin (EP) thermal conductivity composites. The thermal conductivity coefficient of the composites with 60% mass fraction of modified BN is 1.052 W/mK, five times higher than that of native EP (0.202 W/mK). The mechanical properties of the composites are optimal with 10 wt% BN. The thermal decomposition temperature, dielectric constant, and dielectric loss increase with the addition of BN. For a given BN loading, the surface modification of BN by KH550 exhibits a positive effect on the thermal conductivity and mechanical properties of the BN/EP composites. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The silicon carbide whisker (SiCw) and silicon carbide particle (SiCp) were employed to prepare polystyrene/silicon carbide whisker/silicon carbide particle (PS/SiCw/SiCp) thermal conductivity composites, and the titanate coupling reagent of NDZ-105 was introduced to functionalize the surface of fillers. The thermal conductive coefficient λ improved from 0.18 W/mK for native PS to 1.29 W/mK for the composites with 40% volume fraction of SiCw/SiCp (volume fraction, 3 : 1) hybrid fillers. Both the thermal decomposition temperature and dielectric constant of the composites increased with the addition of SiCw/SiCp hybrid fillers. At the same addition of SiCw/SiCp hybrid fillers, the surface modification of hybrid fillers by NDZ-105 could improve the thermal conductivity and the mechanical properties of the composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Graft polymerization of vinyltriethoxysilane (VTES) onto styrene‐butadiene rubber (SBR) was carried out in latex using benzoic peroxide (BPO) as an initiator. The concentration of VTES effecting on vulcanization characteristics, mechanical properties and thermal properties of VTES‐grafted SBR (SBR‐g‐VTES) were investigated. The grafting of VTES onto SBR and its pre‐crosslinking were confirmed by attenuated total teflectance‐Fourier transform infrared reflectance and proton nuclear magnetic resonance. The mechanism of graft polymerization was studied. The results revealed that the minimum torque, optimum cure time, tensile strength, thermal decomposition temperature, and glass transition temperature (Tg) all increased with the increasing concentration of VTES. But the grafting efficiency of VTES, rate of vulcanization, and elongation at break of the SBR‐g‐VTES decreased. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Rational manipulation of composition and microstructure design is recognized as an effective pathway to realize multifunctional high‐performance microwave absorber. In this work, necklace‐like hollow polyacrylonitrile (PAN)/carbon nanofibers are designed and constructed through a simple continuous electrospinning‐carbonization‐etching route. Specifically, by varying the carbonization temperature, the ratio of PAN to carbon content of necklace‐like hollow PAN/carbon nanofibers can be effectively regulated, resulting in tunable electromagnetic parameters and conductive loss capacities. After that, the hollow structure is further introduced to improve the feature of lightweight, impedance‐matching characteristics, and interfacial polarization loss ability. Accordingly, the necklace‐like hollow PAN/carbon nanofibers exhibited a frequency bandwidth of 6.60 GHz and a minimum reflection loss of −44.73 dB at 1.76 mm. Both the experimental and theoretical simulation results indicated that the obtained necklace‐like hollow PAN/carbon nanofibers possessed the high chemical stability and excellent microwave absorbing performance, endowing them as the excellent candidates for microwave absorbers in the extreme conditions. Therefore, the findings not only offered a simple pathway to rationally manipulate composition and microstructure but also provided a novel technique to make the most of hollow engineering for strengthening interface polarization loss. [ABSTRACT FROM AUTHOR]

The demand for low‐frequency microwave absorption materials is becoming more and more urgent. Novel shape anisotropy chain‐like CoNi is fabricated using polyvinylpyrrolidone as a shape‐directing agent via solvothermal method, which is then mixed with polydimethylsiloxane (PDMS) to prepare corresponding multifunctional chain‐like CoNi/PDMS composite films. Shape anisotropy and strong magnetic coupling effect of chain‐like CoNi enhance natural resonance and magnetic loss capability. The minimum reflection loss (RLmin) is −50.5 dB and low‐frequency effective absorption bandwidth (EAB) is 1.04 GHz (2.64–3.68 GHz) at 3.9 mm for chain‐like CoNi. The corresponding 18 vol% chain‐like CoNi/PDMS composite films present optimal low‐frequency microwave absorption performance with RLmin of −56.7 dB and low‐frequency EAB of 1.04 GHz (2.96–4.00 GHz) at 4.1 mm, which is far superior to 18 vol% spherical CoNi/PDMS composite films with RLmin of −9.5 dB. Meantime, the in‐plane and inter‐plane thermal conductivity coefficients of 18 vol% chain‐like CoNi/PDMS composite films are 2.05 and 0.61 W m−1 K−1, about 1.5 times higher than 18 vol% spherical CoNi/PDMS composite films (1.36 and 0.42 W m−1 K−1), also 220% and 190% higher than pure PDMS (0.64 and 0.21 W m−1 K−1). This composite films with low‐frequency microwave absorption and thermal conductivity can broaden applications in 5G communications and flexible electronics. [ABSTRACT FROM AUTHOR]