文献类型：期刊文献

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

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

机构：[1]Univ Tokyo, Grad Sch Frontier Sci, Dept Adv Mat Sci, Chiba 2778561, Japan;[2]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[3]Glaizer Grp, F-92240 Malakoff, France;[4]Hosei Univ, Dept Chem Sci & Technol, Tokyo 1848584, Japan;[5]Tokyo Inst Technol, Dept Organ & Polymer Mat, Tokyo 1528552, Japan;[6]Japan Sci & Technol Agcy, Precursory Res Embryon Sci & Technol PRESTO, Chiyoda Ku, Tokyo 1020075, Japan

年份：2011

卷号：7

期号：8

起止页码：4032

外文期刊名：SOFT MATTER

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000289173500050)】；

基金：This work has been financially supported by PRESTO-JST. The GISAXS experiments were performed at Photon Factory with the approval numbers of 2007G126 and 2009G149.

语种：英文

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 CO2-philic fluorine containing block and high glass transition temperature (T-g) blocks, such as poly[4(1-adamantyl)styrene-b-perfluorooctylethyl methacrylate] (P(AdSt-FMA)) and poly[alpha-methylstyrene-b-perfluorooctylethyl methacrylate] (P(AMSt-FMA)). In particular, PAdSt has a T-g close to 250 degrees C due to the bulky adamantyl group attached to the polystyrene backbone. Although high-T-g blocks (polymers) lack processability in general, CO2 effectively plasticizes and reduces the T-g of the high-T-g 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 (T-s), CO2 pressure and depressurization temperature (T-d), 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 degrees C.