文献类型：期刊文献

英文题名：Self-assembly and photo-responsive behavior of novel ABC₂-type block copolymers containing azobenzene moieties

作者：Wang, Yingying[1];Lin, Shaoliang[1];Zang, Minghui[1];Xing, Yaohui[1];He, Xiaohua[2];Lin, Jiaping[1];Chen, Tao[1]

机构：[1]E China Univ Sci & Technol, Shanghai Key Lab Adv Polymer Mat, Key Lab Ultrafine Mat, Minist Educ,Sch Mat Sci & Engn, Shanghai 200237, Peoples R China;[2]E China Normal Univ, Dept Chem, Shanghai 200062, Peoples R China

年份：2012

卷号：8

期号：11

起止页码：3131

外文期刊名：SOFT MATTER

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000300571600013)】；

基金：This work was supported by National Natural Science Foundation of China (51103044, 21174038 and 50925308) and by Natural Science Foundation of Shanghai (10ZR1407800). Support from Projects of Shanghai Municipality (11QA1401600) and Fundamental Research Funds for the Central Universities (20100074120001 and WD0914031) is also appreciated.

语种：英文

摘要：The self-assembly behavior and photo-responsive properties of novel azobenzene based copolymers poly(ethylene oxide) monomethyl ether-block-polystyrene-block-{poly[6-(4-methoxy-azobenzene-4'-oxy) hexylmethacrylate]}(2) [MPEO-b-PS-b-(PMMAZO)(2)] with various block lengths of PMMAZO segments in aqueous media were studied by means of transmission electron microscopy (TEM), scanning electron microscopy (SEM), laser light scattering (LLS) and UV-Vis spectrophotometry. It was found that the critical water content for the aggregate formation increases with the PMMAZO weight fraction. By tailoring the molecular structure and copolymer concentration, various self-assembled aggregates were obtained. At a lower concentration, all the copolymers self-assembled into simple vesicles. With increasing the polymer concentration, large compound vesicles were formed. The photo-sensitive properties of the formed aggregates were also studied. Upon irradiation with a polarized light, the aggregates were elongated. Large compound vesicles were found to deform into compact spindles with a very large axial ratio.