Key words: polymers, porosity, supercritical fluids, carbon dioxide
Previously developed by authors two-stage method for creating a desired porosity is applied to several polymeric materials, such as polytetrafluoroethylene, ultra high-molecular weight polyethylene, polyether ether ketone, polyaryl ether ketone 11, polyamide 6, shock-resistant polystyrene, acrylonitrile-butadiene-styrene co-polymer, and polyvinylchloride. It consists of polymer treatment with carbon dioxide in supercritical state and subsequent heating at atmospheric pressure. It is demonstrated that the method gives different results being applied to crystalline and amorphous polymers: no porosity is formed in crystalline materials, whereas substantial porosity (up to 0.9 cm3·g-1) is formed in polymers, in which amorphous domains dominate.