Formation and Photoresponsive Properties of Giant Microvesicles Assembled from Azobenzene-Containing Amphiphilic Diblock Copolymers

• Published in: Macromolecular chemistry and physics Vol. 208; no. 9; pp. 955 - 963
• Main Authors: Su, Wei, Han, Kuo, Luo, Yanhua, Wang, Zhong, Li, Yinmei, Zhang, Qijin
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 04.05.2007; WILEY‐VCH Verlag; Wiley
• Subjects: amphiphilic diblock copolymers; Applied sciences; azobenzene; Exact sciences and technology; H-aggregation; photo-induced deformation; Physicochemistry of polymers; self-assembly; Vesicle; photo-induced deformation; H-aggregation; azobenzene; Acrylic acid copolymer; Deformation; amphiphilic diblock copolymers; Photoinduced effect; Experimental study; Azo compound; Monodispersed polymer; self-assembly; Free radical polymerization; Chain transfer; Side chain; Preparation; Diblock copolymer; Radiation effect; Light sensitive copolymer; Ultraviolet visible spectrum; Acrylate copolymer; Molecular aggregation; Aqueous solution; Amphiphilic polymer
• ISSN: 1022-1352; 1521-3935
• DOI: 10.1002/macp.200600628

Diblock copolymers composed of poly(acrylic acid) and poly{6‐[4‐(4‐methylphenylazo)phenoxy]hexyl acrylate} (PAA‐block‐PAzoM) were synthesized by RAFT polymerization. In a mixture of H2O and THF, PAA‐block‐PAzoM self‐assembled into giant spherical microvesicles, which were dispersed in the mixture. Using UV‐vis spectroscopy and optical microscopy, it is demonstrated that the spherical shape of the vesicles results from a framework composed of the azobenzene H‐aggregate skeleton. A plausible structural model of the microvesicles is proposed, and a discussion on the formation of H‐aggregates and the photoresponsive properties is presented.