writer：Lei Li*, Caikang Chen, Aijuan Zhang, Xinyu Liu, Ku
keywords：POROUS FILM; BLOCK COPOLYMER; BLOCK-COPOLYMERS; BREATH FIGURES; THIN-FILMS; TEMPLATES; ARRAYS; POLYSTYRENE; ASSEMBLIES; MEMBRANES
source：期刊

Highly ordered honeycomb films are prepared by breath-figure method using an amphiphilic diblock copolymer of polystyrene-block-polyacrylic acid (PS-b-PAA). By simply cross-linking PS matrix via deep ultraviolet (UV) irradiation, both the solvent and thermal stability of the porous films was significantly improved while retaining the three-dimensional (3D) structures. The film surface wettability was changed from hydrophobicity to hydrophilicity by the formed polar groups during the photochemical process. After 6 h UV cross-linking, the honeycomb structures could be preserved up to 320 degrees C, an increase of more than 200 K as compared to the non-cross-linked films. (C) 2008 Elsevier Inc. All rights reserved.