Patterned porous polymeric product and process

摘要

Porous polymeric structures are formed from a polymeric sheet by sequential contact of the sheet with a solvent for the sheet and then a non-solvent for the sheet. All or a portion of each non-porous sheet surface is masked to prevent a portion of a surface of the sheet from contacting the solvent. The structure can be porous through all or a portion of its thickness.