| abstract |
Polyparaxylylene (PPX) polymer films that can be expanded into porous articles that have a node and fibril microstructure are provided. The fibrils contain PPX polymer chains oriented with the fibril axis. The PPX polymer may contain one or more comonomer. PPX polymer articles may be formed by applying PPX to one or both sides of a substrate, such as by vapor deposition. The nominal thickness of the PPX polymer film(s) is less than about 50 microns. The PPX polymer film(s) may be removed from the substrate to form a free-standing PPX polymer film(s), which may then be stretched into a porous article. |