EUROPEAN POLYMER JOURNAL
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2021
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IF 4.598
Li Fan,Qiuxia Peng,Wen Yuan,Xian Li,Huan Hu,Jiajun Ma,Yawen Huang,Junxiao Yang
Low dielectric UV-curable resins are compatible with photolithography and 3D printing technique, and have great potential for use in inter-layered packaging and antenna. However, it is still a challenge to construct photoactive structure which combines low dielectric properties. In the present work, we propose a new type of low dielectric UV-curable resins by employing photoactive silacyclobutene groups. This low dielectric resins were prepared by UV/thermally curing of siloxane-benzocyclobutene oligomers (SBCOs). Oligomeric SBCOs were prepared by the simple hydrolysis-polycondensation of 1,1-dichlorosilacyclobutane followed by termination of the benzocyclobutene groups. In this way, silaycyclobutene and benzocyclobutene groups were simultaneously introduced into the resins to enable UV and thermally curing of SBCOs. The molecular weight of SBCOs were tuned by the ratio of 1,1-dichlorosilacyclobutane and benzocyclobutene-containing monomer. The cured siloxane-benzocyclobutene resins were thermostable, mechanically strong, and had low dielectric properties.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
POLYMER
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2019
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IF 3.771
Yankuan Jing,Hui Niu,Yang Li
This article demonstrates an effective in-situ method for the preparation of ethylene-propylene rubber/silica composites (EPR/SiO 2 ) via continuous process with two stages: in the first stage, functional olefin monomers containing trichlorosilane group (CSO) are designed and the terpolymerization of ethylene/propylene/CSO catalyzed by metallocene catalyst is implemented; in the second stage, by dispersing the SiO 2 directly into the unterminated polymerization solution , the copolymer chains are anchored to the SiO 2 particles via the reaction between the hydroxyl on SiO 2 surface and pendant chlorosilane groups on the EPR chains. The CSO content in the copolymers was tailored in relatively wide range from 0.71 mol% to 4.68 mol%, which provided various chlorosilane groups for the anchoring reaction on SiO 2 surface. Thus a series of EPR/SiO 2 chemical composites (with the SiO 2 content of 13 wt% ∼ 85 wt%) were prepared via the highly efficient elimination reaction between Si-Cl and Si-OH groups. The dispersing morphology and stability of SiO 2 in EPR/SiO 2 composites were compared with that of the physically blended EPR/SiO 2 systems. Owing to the covalent bonding between polymer chains and SiO 2 particles, the problem of compatibility between the rubber and the filler was fundamentally solved.
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
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2022
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IF 9.879
Qianqian Wang,Pengwu Xu,Weijun Yang,Tianxi Liu,Martin Hoch,Piming Ma
The current cross-link method in rubber industry is suffering from the utilization of toxic curing packages and the release of volatile organic compounds (VOCs). In this work, we propose a green cross-link route to make robust rubber materials. To prove this concept, ethylene-vinyl acetate-glycidyl methacrylate copolymer (EVM-GMA) functionalized with silane groups, i.e., EVM-Si(OC 2 H 5 ) 3 as a model rubber was firstly designed by solvent-free compounding. Then, the silane groups of EVM-Si(OC 2 H 5 ) 3 rubber are hydrolyzed and cross-linked with water molecules. The cross-link density, tensile strength and hardness of the EVM-Si(OC 2 H 5 ) 3 rubber increased gradually with temperature up to 200 °C. Subsequently, the water cross-linked EVM-Si(OC 2 H 5 ) 3 rubber was reinforced with silica (SiO 2 ) that created a secondary network via an in situ interfacial reaction between the –OH groups of SiO 2 and the silane groups of EVM-Si(OC 2 H 5 ) 3 . As a consequence, the SiO 2 nanoparticles could be evenly dispersed in the rubber matrix with strong interfacial bonding . The tensile strength and elongation at break of the EVM-Si(OC 2 H 5 ) 3 /SiO 2 nanocomposites reached to 10.0 MPa and 800%, respectively at a SiO 2 loading of 30 phr. Thus, the new cross-link strategy addressed here may promote the development and application of rubber industry in some environmental-friendly domains.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
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2011
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IF 2.78
Shiguo Chen,Shaojun Chen,Song Jiang,Yangmiao Mo,Junxuan Luo,Jiaoning Tang,Zaochuan Ge
Antibacterial agents receive a great deal of attention around the world due to the interesting academic problems of how to combat bacteria and of the beneficial health, social and economic effects of successful agents. Scientists are actively developing new antibacterial agents for biomaterial applications. This paper reports the novel antibacterial agent siloxane sulfopropylbetaine (SSPB), which contains reactive alkoxysilane groups. The structure and properties of SSPB were systematically investigated, with the results showing that SSPB contains both quaternary ammonium compounds and reactive siloxane groups. SSPB has good antibacterial activity against both Escherichia coli ( E. coli , 8099 ) and Staphylococcus aureus ( S. aureus , ATCC 6538 ). The minimal inhibition concentration is 70 μmol/ml SSPB against both E. coli and S. aureus . In addition, the SSPB antibacterial agent can be used in both weak acid and weak alkaline environments, functioning within the wide pH range of 4.0–9.0. The SSPB-modified glass surface killed 99.96% of both S. aureus and E. coli organisms within 24 h. No significant decrease was observed in this antibacterial activity after 20 washes. Moreover, SSPB does not induce a skin reaction and is nontoxic to animals. Thus, SSPB is an ideal candidate for future applications as a safe, environmentally friendly antibacterial agent.
研究领域:
材料科学
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化学
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生物技术
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）