Formation of honeycomb‐patterned microporous films based on a fluorinated poly(siloxane imide) segmented copolymer

The preparation of honeycomb‐patterned microporous films from a soluble fluorinated poly(siloxane imide) segmented copolymer (PSI) by means of water‐droplet templating is reported first in this article. The fluorinated PSI was synthesized from 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride, 2,2‐bis[4‐(4‐aminophenoxy)phenyl]hexafluoropropane, and diamine‐terminated poly(dimethyl siloxane) by condensation polymerization. The obtained copolymer had good solubility in chlorinated solvents (chloroform, dichloromethane, and 1,2‐dichloroethane), good thermal stability, and a microphase‐separated amorphous structure. The effects of the copolymer concentration, atmospheric humidity, and solvent properties on the pattern formation were investigated. The results show that the film fabricated from the copolymer solution with chloroform as the solvent at a humidity of 90% and a concentration of 0.5 g/L had the most regular honeycomb‐patterned micropores. We could tailor the pore shape and size by changing the copolymer concentration or the atmospheric humidity. The prepared regular honeycomb‐patterned microporous PSI films have potential applications in cell culture and tissue engineering. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011