Nanostructures and surface hydrophobicity of self-assembled thermosets involving epoxy resin and poly(2,2,2-trifluoroethyl acrylate)-block-poly(ethylene oxide) amphiphilic diblock copolymer.
Nanostructures and surface hydrophobicity of self-assembled thermosets involving epoxy resin and poly(2,2,2-trifluoroethyl acrylate)-block-poly(ethylene oxide) amphiphilic diblock copolymer.
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DOI：
10.1021/jp8082198
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发表时间：
2009-01
期刊：
影响因子：
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通讯作者：
Fangping Yi;Sixun Zheng;Tianxi Liu
中科院分区：
文献类型：
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作者：
Fangping Yi;Sixun Zheng;Tianxi Liu
以2,2,2-三氟丙烯酸乙酯为链转移剂，采用可逆加成-断裂转移聚合法制备了聚（2,2,2-三氟丙烯酸乙酯）-嵌段聚（环氧乙烷）（PTFEA-b-PEO）两亲性二嵌段共聚物。将两亲二嵌段共聚物掺入环氧树脂中制备纳米结构环氧热固性树脂。采用原子力显微镜、小角x射线散射和动态力学分析等手段对纳米结构进行了研究。根据固化反应前后嵌段共聚物与环氧树脂亚链的混相性判断，纳米结构的形成遵循自组装机制。静态接触角测量结果表明，含PTFEA-b-PEO二嵌段共聚物的纳米结构热固性材料表面疏水性明显增强，表面自由能明显降低。表面性能的改善归因于两亲二嵌段共聚物的含氟亚链（即PTFEA嵌段）在纳米结构热固性材料表面的富集，表面原子力显微镜和能量色散x射线光谱证明了这一点。
Poly(2,2,2-trifluoroethyl acrylate)-block-poly(ethylene oxide) (PTFEA-b-PEO) amphiphilic diblock copolymer was synthesized via the reversible addition-fragmentation transfer polymerization of 2,2,2-triffluroethyl acrylate with dithiobenzoyl-terminated poly(ethylene oxide) as a chain-transfer agent. The amphiphilic diblock copolymer was incorporated into epoxy resin to prepare the nanostructured epoxy thermosets. The nanostructures were investigated by means of atomic force microscopy, small-angle X-ray scattering, and dynamic mechanical analysis. In terms of the miscibility of the subchains of the block copolymer with epoxy after and before curing reaction, it is judged that the formation of the nanostructures follows the mechanism of self-assembly. The static contact angle measurements indicate that the nanostructured thermosets containing PTFEA-b-PEO diblock copolymer displayed a significant enhancement in surface hydrophobicity as well as a reduction in surface free energy. The improvement in surface properties was ascribed to the enrichment of the fluorine-containing subchain (i.e., PTFEA block) of the amphiphilic diblock copolymer on the surface of the nanostructured thermosets, which was evidenced by surface atomic force microscopy and energy-dispersive X-ray spectroscopy.