title: Directional photomanipulation of breath figure arrays.
abstract: Porous polymeric films are of paramount importance in many areas of modern science and technology. However, processing methods typically based on direct writing, imprint, and lithography techniques have low throughput and are often limited to specific fabricated shapes. Herein, we demonstrate the directional photomanipulation of breath figure arrays (BFAs) formed by an azobenzene-containing block copolymer to address the aforementioned problems. Under the irradiation of linearly polarized light, the round pores in the BFAs were converted to rectangular, rhombic, and parallelogram-shaped pores in 30 min, due to the anisotropic mass migration based on the photo-reconfiguration of the azobenzene units. Through a secondary irradiation after rotating the sample by 90°, the transformed pores were apparently recovered. Therefore, this non-contacted, directional photomanipulation technique in conjunction with breath figure processing opens a new route to nano/microporous films with finely tuned features.
authors.affiliation: Shanghai Key Laboratory of Advanced Polymeric Materials, Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237 (China).
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Can
authors.initials: C
authors.lastname: Du
authors.forename: Xiaofan
authors.initials: X
authors.lastname: Wang
authors.forename: Xiaohua
authors.initials: X
authors.lastname: He
authors.forename: Jiaping
authors.initials: J
authors.lastname: Lin
authors.forename: Lei
authors.initials: L
authors.lastname: Li
authors.forename: Shaoliang
authors.initials: S
authors.lastname: Lin
keywords: block copolymers; breath figures; microarrays; photomanipulation; thin films