Superior nanoporous polyimides via supercritical CO2 drying of jungle-gym-type polyimide gels
Superior nanoporous polyimides via supercritical CO2 drying of jungle-gym-type polyimide gels
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DOI：
10.1002/marc.200600587
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发表时间：
2007-01-05
影响因子：
4.6
通讯作者：
Horie, Kazuyuki
中科院分区：
文献类型：
--
作者：
Kawagishi, Ken;Saito, Hirornu;Horie, Kazuyuki
我们报告了一种新型的纳米多孔聚酰亚胺，由丛林健身房型刚性聚酰亚胺凝胶通过超临界CO2干燥形成。利用超临界CO2干燥避免纳米结构的坍塌，孔隙率达到90 vol.-%以上。在50-800 nm范围内，我们发现了多种多样的纳米孔结构，如脆片、微小网络和高度连接的珠状结构。这些特征结构是凝胶化过程中端交联和热亚酰化两种化学反应引起的液液相分离和结晶的竞争过程形成的。
We report novel nanoporous polyimides formed from jungle-gym-type rigid polyimide gels by supercritical CO2 drying. By virtue of supercritical CO2 drying to avoid the collapse of nanostructure, porosity above 90 vol.-% was achieved. We found a rich variety of nanoporous structures in the range of 50-800 nm such as crisp fragments, minute network, and highly-connected beads. These characteristic structures were formed by the competitive progress of liquid-liquid phase separation and crystallization induced due to the two chemical reactions of end-crosslinking and thermal imidization during gelation.