The origin of size-selective gas transport through polymers of intrinsic microporosity

摘要: An analysis of the diffusivity light gases through Polymers Intrinsic Microporosity (PIMs) shows that smaller H2 and He gas molecules have a transport mechanism is similar to porous materials, whereas larger molecules, CH4, N2, O2 CO2, show activated conventional dense polymers. A typical defining feature PIMs, which differentiates their properties from other high free volume polymers, glassy polymers rubbers, change in slope plot diffusion coefficient as function diameter, with stronger size-selective trend for than H2. Deviation this observed polymer-gas combination strong mutual affinity (i.e. an amine modified PIM CO2). Molecular modelling size selectivity PIMs originates presence bottlenecks between individual elements. For latest generation highly rigid ageing studies differentially reduced thus further enhancing size-selectivity.