Fabrication of durable honeycomb-patterned films of poly(ether sulfone)s via breath figures

Honeycomb-patterned porous films of poly(ether sulfone) (PES) are prepared via breath figures (BF), in which dichloromethane (DCM) is used as the solvent, although the solubility of PES in DCM is relatively low. It is found that the use of a DCM suspension of PES as the casting solution and the addition of an amphiphilic block copolymer, poly(styrene-co-maleic acid) partial isobutyl ester (PSME), assist the stabilization of water-droplet arrays during the BF process, contributing to improved pattern regularity, and finally leading to the formation of highly ordered honeycomb-patterned films of PES. A synergetic effect of concentration and humidity on the film morphology is discovered and systematically investigated. Moreover, the resultant films possess enhanced resistance to strong acid and base solutions under heating, indicating their promising applications under harsh conditions. Highly ordered honeycomb-patterned films of poly(ether sulfone) (PES) are fabricated via breath figures by using dichloromethane as the solvent and a block copolymer, poly(styrene-co-maleic acid) partial isobutyl ester (PSME), as the additive. A novel synergetic effect of humidity and concentration on the morphology is investigated and utilized for pattern modulation. These PES films possess enhanced stability under harsh conditions, indicating promising applications with less limitation.