文献类型：期刊文献

英文题名：Thermally robust nanocellular thin films of high-Tg semifluorinated block copolymers foamed with supercritical carbon dioxide

作者：Zhang, Rui[1]; Dutriez, Cedric[2]; Sugiyama, Kenji[3]; Ishizone, Takashi[4]; Yokoyama, Hideaki[5,6]

机构：[1] State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China; [2] Glaizer Group, 32 rue Guy Moquet, 92240 Malakoff, France; [3] Department of Chemical Science and Technology, Hosei University, Tokyo 184-8584, Japan; [4] Department of Organic and Polymeric Materials, Tokyo Institute of Technology, Tokyo 152-8552, Japan; [5] Department of Advanced Materials Science, Graduate School of Frontier Sciences, University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa Chiba 277-8561, Japan; [6] Precursory Research for Embryonic Science and Technology [PRESTO], Japan Science and Technology Agency, 3-5, Sanbancho, Chiyoda-ku Tokyo 102-0075, Japan

年份：2011

卷号：7

期号：8

起止页码：4032

外文期刊名：Soft Matter

收录：EI(收录号：20111513904024)

语种：英文

外文关键词：Glass transition - Supercritical fluid extraction - Thin films - Carbon films - Styrene - Block copolymers

摘要：Nanoscopic porous and cellular materials with high thermal stability are demanded for a variety of applications. We fabricated thermally robust nanocellular thin films using block copolymer templated carbon dioxide foaming (BCTCF). We synthesized semi-fluorinated block copolymers having a CO 2-philic fluorine containing block and high glass transition temperature (Tg) blocks, such as poly[4-(1-adamantyl)styrene-b- perfluorooctylethyl methacrylate] (P(AdSt-FMA)) and poly[α-methylstyrene- b-perfluorooctylethyl methacrylate] (P(AMSt-FMA)). In particular, PAdSt has a Tg close to 250 °C due to the bulky adamantyl group attached to the polystyrene backbone. Although high-Tg blocks (polymers) lack processability in general, CO2 effectively plasticizes and reduces the Tg of the high-Tg blocks, swells the fluorinated block domains, and leaves empty nanocells in the fluorinated block domains after CO2 was removed. We optimized process conditions, such as saturation temperature (Ts), CO2 pressure and depressurization temperature (Td), to introduce nanoscopic cells in such high-T g matrices, and achieved porosities as high as 0.25, average diameter about 20 nm and remarkable thermal robustness up to more than 200 °C. ? The Royal Society of Chemistry 2011.