JOURNAL OF NON-CRYSTALLINE SOLIDS
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2025
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IF 3.5
Han Zeng,Maoqiang Bi,Zhonghe Tong,Yingtai Du,Xi Chen,Tianyan Jiang
In this study, the enhancement mechanism of SiO 2 modified by different silane coupling agents (SCA) on the moisture resistance, thermal properties and electrical insulation properties of epoxy resin (EP) composites is discussed. Through the combination of experimental tests and molecular dynamics (MD) simulations, the performance differences of five systems (EP, SiO 2 -EP, KH550 / SiO 2 -EP, KH560 / SiO 2 -EP, KH570 / SiO 2 -EP) in water absorption, glass transition temperature ( T g ) and volume resistivity are analyzed. The changes of free volume fraction (FFV), interaction energy, number of hydrogen bonds and diffusion behavior of water molecules are revealed from the microscopic point of view. The experimental results show that the introduction of modified SiO 2 significantly improves the moisture resistance, thermal properties and electrical properties of EP. Among them, KH550 modified SiO 2 has the best effect, T g increases by 12.3 %, volume resistivity increases by 22.1 %, and water absorption rate decreases by 21.9 % at 60 °C. MD simulations further confirm that the nano-SiO 2 modified by SCA can effectively limit the diffusion of water molecules and reduce the effect of temperature on the mean square displacement (MSD) of the system. The KH550 / SiO 2 -EP system has the smallest free volume and the highest number of hydrogen bonds, which effectively inhibits the diffusion of water molecules and the movement of molecular chains. This study provides a theoretical basis and material design strategy for the application of epoxy composites in hygrothermal environments.
研究领域:
高分子材料科学
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复合材料工程
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电气绝缘技术
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材料化学
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纳米功能材料
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高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2022
·Vol. 57
·期 2
·1156-1173
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IF 4.682
Feng Zhiqiang,Liu Xiaohong,Zhang Wenchao,Zeng Juanjuan,Liu Jiaming,Chen Bifang,Lin Jiaming,Tan Liqin,Liang Liyan
The field of microelectronic devices and 5G communication has an increasing demand for polymer composites with low dielectric constant, low dielectric loss, and good hydrophobicity. However, traditional polymer composites cannot simultaneously satisfy them, which severely hinders their application. In this work, a liquid crystal epoxy resin (LCE 4 ) consisted of a flexible chain and rigid mesogenic unit was prepared and cured with methylhexahydrophthalic anhydride (MHHPA). And the mechanism of the curing reaction and the phase structure of the liquid crystal epoxy resins were investigated. In addition, dielectric hydrophobic liquid crystal epoxy nanometer composite materials were successfully prepared with functionalized mesoporous silica (SBA-15) as a filler. The results showed that pure LCE 4 exhibited excellent dielectric properties and thermal stability. Compared with pure LCE 4 , the composite material for SBA-15 modified with KH560 displayed lower dielectric constant, lower dielectric loss, higher glass transition temperature, and better hydrophobicity. For example, with a 0.5 wt% SBA-15, the dielectric constant and dielectric loss of the composite material were as low as (2.35, 0.025) compared with pure LCE 4 (3.25, 0.036) that was reduced by 24.7% and 31%. In addition, the glass transition temperature and water contact angle are increased by 16 °C and 14°, respectively. Composites also showed good thermal stability and mechanical properties. The reasons may mainly be derived from the internal structure of LCE 4 , the effective modification of mesoporous SBA-15 by KH560, and the excellent dispersion of organic and inorganic phases. Graphical abstract
研究领域:
材料科学
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高分子化学
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电气工程
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纳米技术
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DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2023
·
IF 13.1
Li Zhang,Qian Zhang,Weihong Cao,Zhenghong Guo,Zhengping Fang,Juan Li,Peng Chen
A phosphorous-silicon (SiP) precursor was synthesized using p-phthalaldehyde, (3-aminopropyl) triethoxysilane and 9,10-dihydro-9-oxa-10-phosphaphenantrene-10-oxide. The SiP was used to fabricate a phosphorous-silicon hybrid microsphere (SiP-M) via the sol-gel method. The SiP-M was employed to enhance the flame retardancy of poly (butylene adipate-co-terephthalate) (PBAT). The results indicate that PBAT containing 0.1 wt% of SiP-M displays a UL-94 V0 rating and a limiting oxygen index (LOI) value of 26.5 vol%. Meanwhile, PBAT containing 1.0 wt% SiP-M exhibits a UL-94 V0 rating and a LOI value of 29.8 vol%, and some reductions in peak heat release rate , total heat release, and total smoke production. The SiP-M functions in both the gas phase and condense phase in the PBAT blend, and the former is predominant. In addition, a coupling agent KH560 was used to modify the interface adhesion between PBAT and SiP-M. The tensile strength and elongation at the break of PBAT blends are enhanced by an appropriate amount of KH560. This work provides an efficient method for preparing flame-retardant PBAT without deteriorating its mechanical properties .
研究领域:
材料科学
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高分子化学
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消防安全工程
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高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2023
·
IF 4.6
Shizhen Jia,Hui Cao,Xiangchao Liang,Shuang Wu,Rong Zeng,Mei Tu
Medical sponges are widely used in wound management, however the adhesion of bacterial or wound tissue to them may cause infection or secondary damage to patients. In this work, anti-bioadhesive polyvinyl alcohol-formaldehyde sponges with zwitterionic coating were prepared by the dip-coating process using the reactive zwitterionic phosphorylcholineated polyvinylamine (PVAm-PC) and commercial silane coupling agent KH560 at different mass ratios, and their structure, physicochemical, biocompatible and anti-bioadhesive properties were investigated. As compared to pristine sponges, the PVAm-PC-KH560 (PPK) modified sponges with the interconnected pore structure had almost unchanged water vapor transmission rate but decreased swelling degree to a certain extent possibly due to the formation of rigid Si– O –Si networks in the sponges. In vitro biological evaluation confirmed that PVAm-PC-KH560 modified sponges were not cytotoxic and had good resistance to bacteria adhesion with only ∼16% and ∼11% relative bacterial adhesion rate for E. coli and S. aureus respectively. And the optimized PPK-2 sponge showed the best comprehensive bacterial adhesion inhibition properties. Further adhesion assay of L929 fibroblasts showed that PPK-2 sponge could significantly reduce the adhesion of L929 fibroblasts. The results strongly suggested that dip-coating with zwitterionic PVAm-PC and KH560 may provide a promising and facile method to construct an anti-bioadhesive surface for biomedical applications.
研究领域:
生物医学工程
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材料科学
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生物材料
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组织工程
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高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2024
·Vol. 35
·期 30
·1-12
·
IF 2.8
Liu Wei,Zhang Weichao,Shen Fenglei
In this paper, 3-glycidyl ether oxypropyltrimethoxysilane (KH560) was incorporated into the reaction product of polyether amine (2-APPG) and polyethylene glycol diglycidyl ether (PEDGE) to create an organic-inorganic hybrid polymer. The hybrid polymer underwent the catalytic hydrolysis of a hydrochloric acid-ethanol solution and was then swelled in the liquid electrolyte containing lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) to form the novel hybrid polymer electrolyte (GPE). The TGA results indicate that the samples underwent a 4% mass loss within the temperature range of 25 °C to 280 °C. The electrochemical test results show that the conductivity of the GPE reaches 1.57 × 10 −3 S/cm at room temperature, and the lithium-ion transference number (t + ) reaches 0.22. In addition, electrochromic devices prepared with APK-1 as the electrolyte exhibit good light density change (∆ (OD) = 0.134), coloring efficiency of 153.3 cm 2 /C, and stability with 400 stable cycles within the voltage range of -2.5 V to 2.5 V. The above tests demonstrate the enormous potential of the proposed GPEs in the application of electrochromic devices.
研究领域:
材料科学
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电化学
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高分子科学
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电致变色器件
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DOI
高影响因子
危险品化学品经营许可证（带存储）