Polymers of Intrinsic Microporosity: Copolymers, improved Synthesis and Applications as Membrane Separation Material
AbstractIntrinsic microporosity is one of the most important properties of high free volume polymers. If one arranges all known polymers by increasing free volume in a continuous line, at the endpoint, merely a very few polymers with extremely high free volume of above 20% can be named. Today, only some polyacetylenes (best known polytrimethylsilylpropyne (PTMSP)), Teflon copolymers (Teflon® AF-types, Hyflon® AD), one silylated polynorbornene and PIM polymers are identified. PIM polymers, known since 2004 , are ladder type polycondensates composed of flat dioxane rings and sites of contortion. Their exceptional basic properties as membrane separation materials have been recovered recently .