Polymers
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2020
·Vol. 12
·期 3
·534
·
IF 3.426
Jingyu Wang,Hui Shi,Pinlie Zhu,Yuanjie Wei,Jianwei Hao
A zeolite imidazole framework (ZIF-67) was assembled onto the surface of ammonium polyphosphate (APP) for preparing a series multifunctional flame-retardant APP-ZIFs. The assembly mechanism, chemical structure, chemical compositions, morphology, and specific surface area of APP-ZIFs were characterized. The typical APPZ1 and APPZ4 were selected as intumescent flame retardants with dipentaerythritol (DPER) because of their superior unit catalytic efficiency of cobalt by thermogravimetric analysis. APPZ1 and APPZ4 possessed 6.8 and 92.1 times the specific surface area of untreated APP, which could significantly enhance the interfacial interaction, mechanical properties, and migration resistance when using in ethylene-vinyl acetate (EVA). With 25% loading, 25% APPZ4/DPER achieved a limiting oxygen index value of 29.4% and a UL 94 V-0 rating, whereas 25% APP/DPER achieved a limiting oxygen index value of only 26.2% and a V-2 rating, respectively. The peak of the heat release rate, smoke production rate, and CO production rate respectively decreased by 34.7%, 39.0%, and 40.1%, while the char residue increased by 91.7%. These significant improvements were attributed to the catalytic graphitization by nano cobalt phosphate and the formation of a more protective char barrier comprised of graphite-like carbon.Keywords:zeolite imidazole framework;APP;interface assembly;flame retardant
研究领域:
材料科学
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化学工程
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高分子科学
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消防安全工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2025
·
IF 2.8
Xue Tao,Fangfang Gong,Wenzeng Wang,Jingyu Wang,Lijun Qian,Jianwei Hao
In recent years, ammonium polyphosphate (APP) based intumescent flame-retardant systems (IFR) were widely used in ethylene-vinyl acetate copolymer (EVA). However, APP-based IFR have poor water and migration resistance. This paper introduced metal alginates to improve flame retardant efficiency and water resistance of IFR intramolecularly. The alginates IFR(IMA) with three sources and one synergistic agent were prepared by acid source and gas source (APP) and carbon source dipentaerythritol (DPER). IMA were APP/DPER assembled by sodium alginate, cobalt alginate and silane coupling agent. IMA significantly improved flame retardant, smoke suppression and migration resistance of EVA. Compared with 25%APP/DPER, the LOI values of 25%ICA increased obviously, UL 94 increased from no grade to V-0, the peak of heat release rate value and total smoke produce value decreased by 36.1% and 16.8%, respectively. The reason was that the transition metal cobalt promotes the efficiency of carbonization and graphitization, and reduces the ratio of CO and aromatic compounds in the gas phase thermal decomposition products. None significant mechanical properties changed after adding the flame retardant The weight loss rate was significantly reduced by immersion in hot water at 70°C. The improvement of water resistance was related to the increase of water contact angle of ICA flame retardants.
研究领域:
高分子科学
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材料工程
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消防安全工程
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阻燃材料
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DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2025
·
IF 8
Zhipeng Zhang,Yao Yin,Kai Liang,Ranzhao Shen,Xu Fan,Bihe Yuan
The high flammability and severe dripping behavior of ethylene-vinyl acetate (EVA) limit its widespread application. It remains a persistent challenge to enhance the flame retardancy and smoke suppression performance of EVA composites while maintaining their tensile properties. In this study, a microencapsulated P/N/B-based flame retardant, referred to as MBPAPP, was synthesized via a one-pot method. The flame retardant consists of a melamine-boric acid composite (MA-BA, shell) and piperazine pyrophosphate (PAPP, core). At a loading of 20 wt% MBPAPP, EVA/MBPAPP composite achieves a UL-94 V-0 rating without dripping. In the cone calorimetry test, compared with EVA/PAPP, EVA/MBPAPP exhibits reductions in the peak heat release rate (50.5 %), total heat release (16.9 %), total smoke production (17.1 %), and the peak of CO content (52.5 %). This is attributed to the fact that EVA/MBPAPP forms a boron-containing char layer composed of B-O and B-N structures, contributing to the enhancement of compactness and thermal stability. Moreover, compared with PAPP, microencapsulation enhances the compatibility between modified MBPAPP and EVA, mitigating the deterioration of tensile properties in the composite.
研究领域:
材料科学
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高分子科学
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消防安全工程
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化学工程
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
·
IF 5.518
Meng Liu,Xinyu Tan,Xinyi Li,Jialin Geng,Mengmeng Han,Ke Wei,Xiaobo Chen
Superhydrophobic coatings have aroused increasing interest in many fields. However, the low light transmittance , poor mechanical robustness, and unsatisfactory chemical stability greatly limit the practical application of superhydrophobic coatings. Herein, a robust transparent superhydrophobic coating was prepared through a facile two-step dipping treatment. The coated glass displays good transparency with transmittance about 87 % in the wavelength range of 500–900 nm, remarkable superhydrophobic performance with a water contact angle of 158.8° and a sliding angle less than 1.0°. After a series of durability tests, including grit impact, etching in acidic and alkaline environments, and long-term outdoor exposure, the obtained coating can still maintain good superhydrophobic and transparency, which confirms the obtained coating has good mechanical robustness and chemical stability. Moreover, the coating exhibits good anti-icing property with a longer icing time and can maintain superhydrophobicity after 80 icing/de-icing cycles. It can be believed that such transparent superhydrophobic coating can be applied in many fields, owing to its low-cost and environmentally friendly fabrication method and its good performances in mechanical robustness and chemical stability.
研究领域:
材料科学
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表面工程
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DOI
高影响因子
OPTICAL MATERIALS
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2022
·
IF 3.754
Jintong Lu,Shuangping Yi,Yixuan Zhou,Pengfei Xu,Zhengfa Hu,Weiren Zhao,Yinhai Wang
Metal halide perovskite nanocrystals have excellent prospects in solid-state lighting, flexible display, sensing, and other optoelectronic applications due to their superb photoelectric properties (high quantum efficiency and fast carrier diffusion speed). However, they are susceptible to environmental factors such as ultraviolet radiation and polar solvents. Especially in a water environment, poor stability seriously restricts the application of perovskite optical devices . In this paper, a kind of porous polymer (ethylene-vinyl acetate copolymer , EVA) and perovskite nanocrystals were mixed to form perovskite nanocrystals-EVA composites. The obtained composites were aged in water for 21 days, and the fluorescence enhancement was 170 times. Even in a strongly acidic environment, the fluorescence enhancement was 91 times. The information encryption mode of the composite material can effectively encrypt information in a wet environment due to the change of light wavelength, making a white light-emitting diode (w-LED). This metal halide perovskite nanocrystals-EVA composite will unleash a wide variety of solid-state lighting and flexible display possibilities that are limited by the use of existing methods in humid and strongly acidic environments.
研究领域:
材料科学
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光电技术
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纳米技术
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光子学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
·
IF 15.1
Yuhang He,Zeen Zhang,Hua Ke,Yangcheng Lu
Ethylene content in ethylene–vinyl acetate copolymers (EVA) is a key factor that determines its further usage. While conventional batch reactor for EVA synthesis faces the problem of heterogeneous reaction environment and temperature control. A microflow system was designed to avoid these problems and facilitate the synthesis of EVA with controlled ethylene content. Continuous flow synthesis of EVA by solution free radical copolymerization was realized homogeneously based on this microflow system. 13 C NMR spectra indicate that EVA obtained in microflow system has less ethylene concentrated sequence than EVA obtained in batch reactor. By operating the microflow system in a stop-flow method, we developed a simple kinetic model of copolymerization and measured the reactivity ratios of ethylene and vinyl acetate copolymerization in tert -butyl alcohol and dimethyl carbonate. The microflow system is demonstrated to be a powerful tool in kinetic and mechanism study and engineering application of copolymerization processes involving monomers which are gas phase under conventional condition.
研究领域:
化学工程
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高分子科学
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2025
·
IF 2.8
Huijie Qin,Tongwei Zhang,Lihong Bao,Bo Dang,Jianxi Li
In this research, iron tetroxide (Fe₃O₄) nanoparticles were in situ synthesized on the surface of molybdenum disulfide (MoS 2 ) via a radiation technique to fabricate a MoS₂@Fe₃O₄ hybrid. Notably, the tensile strength and elongation at break of ethylene vinyl acetate (EVA)/magnesium hydroxide (MH) composites were enhanced by 62.5% and 59.1%, respectively, with the addition of one part of the MoS₂@Fe₃O₄ hybrid, attributed to its excellent reinforcing effect. Simultaneously, the peak heat release rate (pHRR) and total heat release of the EVA/MH composite decreased by 45.9% and 14.4%, respectively, while the residue content increased to 43.4%. Furthermore, EVA/MH/MoS₂@Fe₃O₄ composites with one part of the MoS₂@Fe₃O₄ hybrid generated significantly fewer toxic gases (such as CO) compared to EVA/MH composites, demonstrating enhanced fire safety. This study underscores the potential of creating noble metal-free layered composites by integrating cost-effective and eco-friendly Fe₃O₄ co-catalysts, such as MoS₂@Fe₃O₄ hybrids, to improve the fire safety of EVA composites.
研究领域:
材料科学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2025
·
IF 9.7
Cengceng Zhao,Yong Yang,Yanyan Lin,Chao Wang,Xianfeng Wang,Jianyong Yu,Bin Ding
Hypothesis Conventional nanofiber membrane materials exhibit opacity owing to substantial light loss inherent to their structural characteristics, resulting in the invisibility of the face in their product applications, such as masks. In addition, the absence of moisture transfer channels promotes moisture accumulation. To address these limitations, electrospinning technology combined with selective interfiber thermal melting for pore formation has the potential to effectively improve transparency and construct effective mass transfer channels, thereby mitigating structural defects and potentially addressing these performance issues. Experiments Electrospun nanofiber membranes consisting of ethylene vinyl acetate (EVA) and polyacrylonitrile (PAN) nanofibers with physically interlocking structures were fabricated. The selective melting of the EVA nanofiber at 80 °C formed mass transfer channels. Additionally, the composite performance of three-dimensional mass transfer channels with transparency, filtration, and moisture permeability properties was analyzed by validating the structural characterization and mass transfer mechanism studies. Findings The selective fusion of EVA nanofibers formed an optimized light path and achieved the transparency of the nanofiber membranes. Concurrently, EVA and PAN nanofibers established a layered coarse-fine gradient filtration system and moisture-transfer channels. This effectively resolves the traditional performance trade-offs among transparency, protection, and moisture management in nanofiber membranes. The prepared nanofiber materials exhibited a light transmittance of 84.14 % at 550 nm, filtration efficiency of 94.18 % (85 L/min) for PM 0.3 particles, moisture permeability of 5.52 g m −2 h −1 , and air permeability of 119.59 mm s −1 .
研究领域:
材料科学
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纳米技术
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高分子科学
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光学性质
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膜技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2025
·
IF 7.4
Ping Wang,Hongyu Tian,Yiyang Zhou,Tongtong Zhang,Shi Dong,Longen Cheng,Wenbin Luo,Li Yang,Wenxiu Liu,Tian Cao,Mingdi Yang,Daosheng Sun
Developing high-performance composites for maglev train cables that combine excellent flame retardancy, mechanical properties and fatigue resistance is currently a significant challenge in special cable industry. Herein, a multifunctional reactive phosphorus nitrogen flame retardants (UPMDM) with flame retardant and filler surface modification functions was synthesized, and it was employed to control the polymer matrix-filler interactions and the microstructure of ethylene-vinyl acetate copolymer (EVA)-based composite during melt blending. Phosphorus-nitrogen composite flame retardant (MH@UPMDM) could be preformed before melt blending or formed in-situ during melt blending by the reaction between the isocyanate group (-NCO) of UPMDM and the hydroxyl group on the surface of magnesium hydroxide (MH), and the effect of processing type (physical blending/chemical grafting/in-situ reaction) on dispersion kinetics of MH in EVA matrix was investigated. The results indicate preformed MH@UPMDM can play a role in rigid crosslinkers to construct organic-inorganic hybrid network, thus effectively control the dispersion kinetics of the fillers and the filler-matrix interaction in the EVA matrix. Compared with EVA/MH composites, the elongation of EVA/MH@UPMDM composites is increased by nearly 2.2-fold, while it also exhibits an excellent fatigue-resistance under 1.0 × 10 4 th cycles. Furthermore, MH@UPMDM can significantly enhance the flame retardant properties of the composites, the limiting oxygen index (LOI) of EVA/MH@UPMDM composite reaches 33.6%, while its peak heat release rate (PHRR) and total heat release (THR) decreases to 277.82 kW/m 2 and 74.71 MJ/m 2 from 436.66 kW/m 2 and 88.67 MJ/m 2 compared to EVA/MH composites, which may be attributed to the multi-phase synergistic flame retardant mechanism of UPMDM.
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DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 33
·期 14
·2213398
·
IF 19
Congyuan Zhang,Heng Xie,Yu Du,Xiaolong Li,Weilong Zhou,Ting Wu,Jinping Qu
The heat accumulation caused by the high power consumption of continuously upgrading electronic devices puts forward more requirements for the adaptability and durability of the flame retardant materials. Herein, inspired by the soil reinforcement effect of the shelter forest roots nearby the river and shoal, a superhydrophobic flame-retardant ethylene-vinyl acetate (EVA)/aluminum trihydroxide (ATH) composite with root-soil interlocked micro/nanostructure (MEA/PGCC) is prepared by combining the micro-extrusion compression molding and spray coating. The homogeneously dispersed ATH and the EVA with sufficient mechanical strength provide durability for the long-term work of the MEA/PGCC composite. The root-soil interlocked micro/nanostructure provides robust superhydrophobicity with a water contact angle of 156 ± 1.0° and a rolling angle of 4 ± 1.0° for the MEA/PGCC composite which is beneficial to improve acid and alkali tolerance, thermic resistance, and de-icing performance. The synergism of interface and surface function prominently improves the flame retardancy of the MEA/PGCC composite, which presents a limit oxygen index of 42%, and remarkable reduction in peak heat release rate of 64%, total heat release of 23%, and peak smoke production rate of 47%. The proposed method is a promising candidate for the mass production and practical application of the superhydrophobic flame retardant composite.
研究领域:
材料科学
·
化学工程
·
高分子科学
·
消防安全工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2023
·
IF 8.7
Xiaoming Qi,Wenjun Wang,Hongbo Dai,Yaofeng Zhu,Yubing Dong,Shao-Yun Fu,Qingqing Ni,Yaqin Fu
Shape memory polymer fibers (SMPFs) coated with conductive layers are attracting increasing attention in soft robots and wearable electronics. However, the thickness and poor stretchability of the conductive layer hinder its applications. Here, the multifunctional two-way shape memory reduced graphene oxide (RGO)/ethylene–vinyl acetate copolymer (EVA) composite yarn is designed following the “swelling-ultrasonicating” and one-step twisting procedures. These RGO/EVA composite fiber conductive paths connected with each other by constructing the helical conductive network. The RGO/EVA composite yarn presents excellent electro-thermal conversion performance and outstanding load-bearing capability, enabling controlled electro-driven reversible strain (more than 10% reversible strain) and high energy density (72.5 J/kg). Additionally, the composite yarn has great stretchability (130% strain), high strain sensing sensitivity (gauge factor of 7.3), large linear working range (up to 70% strain). This work provides an innovative manufacturing strategy for the RGO/EVA composite yarn with two-way shape memory, electro-driven actuation, and strain sensing performance.
研究领域:
材料科学
·
机器人技术
·
可穿戴技术
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复合材料
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机电系统
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）