Controlled thermal oxidative crosslinking of polymers of intrinsic microporosity towards tunable molecular sieve membranes
Controlled thermal oxidative crosslinking of polymers of intrinsic microporosity towards tunable molecular sieve membranes
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DOI：
10.1038/ncomms5813
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发表时间：
2014-09-01
影响因子：
16.6
通讯作者：
Sivaniah, Easan
中科院分区：
文献类型：
--
作者：
Song, Qilei;Cao, Shuai;Sivaniah, Easan
有机开放框架具有明确的微孔（孔径小于2 nm）结构，是有吸引力的下一代材料的气体吸附，存储，催化和分子水平的分离。聚合物的固有微孔性（PIM）代表了一个范式转变，在概念化的分子筛从传统的有序框架的无序框架与微孔性的非均匀分布。PIM包含具有高气体渗透性但具有损害其分子选择性的异质性水平的微孔的互连区域。在这里，我们报告可控的热氧化交联的PIM的热处理中存在的微量氧气。所得的共价交联网络是热和化学稳定的，机械柔性的，并具有显着的选择性，在渗透率是三个数量级高于商业聚合物膜。这项研究表明，受控的热化学反应可以微妙地调整微孔聚合物内的通道和孔的拓扑结构及其分子筛性能。
Organic open frameworks with well-defined micropore (pore dimensions below 2 nm) structure are attractive next-generation materials for gas sorption, storage, catalysis and molecular level separations. Polymers of intrinsic microporosity (PIMs) represent a paradigm shift in conceptualizing molecular sieves from conventional ordered frameworks to disordered frameworks with heterogeneous distributions of microporosity. PIMs contain interconnected regions of micropores with high gas permeability but with a level of heterogeneity that compromises their molecular selectivity. Here we report controllable thermal oxidative crosslinking of PIMs by heat treatment in the presence of trace amounts of oxygen. The resulting covalently crosslinked networks are thermally and chemically stable, mechanically flexible and have remarkable selectivity at permeability that is three orders of magnitude higher than commercial polymeric membranes. This study demonstrates that controlled thermochemical reactions can delicately tune the topological structure of channels and pores within microporous polymers and their molecular sieving properties.