应浙江加州国际纳米技术研究院、bwin必赢、中国硅酸盐学会溶胶凝胶分会邀请,日本溶胶凝胶学会副理事长、日本京都大学化学系Kazuki Nakanishi副教授来我校访问并举行学术报告。
报告题目:Polyorganosiloxane Macroporous Monoliths for Heat-Insulation, Separation Media and Supported Metal Nanoparticles
报告时间:2016.04.06(周三)上午09:30~11:00
报告地点:紫金港校区•纳米楼330室
邀请人:杨辉、樊先平、郭兴忠
报告摘要:
Organic-inorganic hybrids derived from partially substituted alkoxysilane precursors can offer a variety of monolithic porous materials via a sol-gel process when their hydrolysis-polycondensation reactions are appropriately controlled to parallel the polymerization-induced phase separation. Some of our recent developments are described below.
1. Poly(methylsilsesquioxane) Aerogels: Using methyltrimethoxysilane, MTMS, as a single precursor, monolithic poly(methylsilsesquioxane), PMSQ gels are prepared in the presence of surfactants via acid-base one pot reaction route. Through the preparation optimized for low-density, pure PMSQ aerogels are obtained to exhibit comparable properties with those of tranditional silica aerogels. Moreover, the monolithic PMSQ aerogels can reversibly recover to the original size when uniaxially compressed. Utilizing this “spring-back” property, PMSQ aerogels can be prepared by drying at ambient conditions.
K. KANAMORI et al., Chem. Soc. Rev., 40, 754-770 (2011) and J. Mater. Chem. A, 2, 6525-6531 (2014).
2. Marshmallow-like Macroporous Monoliths. As an extension of PMSQ monoliths, a co-polymerization of MTMS with dimethyldimethoxysilane, DMDMS, was attempted. With an increase of DMDMS/MTMS ratio, the Young’s modulus drastically decreased to give very soft reversibly deformable monolith (marshmallow-like monolith) with larger macropores. Due to its inherent surface hydrophobicity, the marshmallow-like monolith can selectively absorb nonpolar liquid from a physical mixture of oil/water.
G. HAYASE et al., Angew. Chem. Int. Ed., 52 (7), 1986-1989 (2013) and 52(41), 10788–10791 (2013).
3. Hydrogen-silsesquioxane Monoliths. The simplest silsesquioxane, hydrogen silsesquioxane HSQ, has been studied for a long time. Using the polymerization-induced phase separation technique, we have succeeded to prepare monoliths with well-defined continuous macropores while preserving all the Si-H bonds contained in the precursor. Liquid-phase contact of noble metal ions onto the Si-H resulted in an instantaneous formation of metal nanoparticles firmly immobilized in the mesopores of HSQ monoliths. An application of embedded noble metal nanoparticles to various catalytic reactions has proven excellent efficiency and recyclability.
N. MOITRA et al., Adv. Func. Mater., 23, 2714-2722 (2013); Langmuir, 29, 12243-12253 (2013); New J. Chem. 38, 1144-1149 (2014)..
Kazuki Nakanishi副教授简介:
Kazuki Nakanishi, Associate Professor, Department of Chemistry, Graduate School of Science, Kyoto University. He is engaged in sol-gel derived porous materials. He is the author of >260 publications with >6500 total citations, the holder of >50 patents, and the co-author of 20 books. He has been serving as a co-editor of Journal of Sol-Gel Science and Technology since April 2009. He is the member of the American Ceramic Society, Materials Research Society, Board Members of Japanese Sol-Gel Societies, and also the member of several other Japanese societies related to materials and analytical chemistry.
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浙江加州国际纳米技术研究院
bwin必赢
中国硅酸盐学会溶胶凝胶分会
2016年03月30日