Water‐soluble triply‐responsive homopolymers of N,N‐dimethylaminoethyl methacrylate with a terminal azobenzene moiety |
| |
Authors: | Xinde Tang Xiaochao Liang Longcheng Gao Xinghe Fan Qifeng Zhou |
| |
Institution: | 1. Institute of New Materials, Shandong Jiaotong University, Jinan 250023, China;2. Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Department of Polymer Science and Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China |
| |
Abstract: | Novel water‐soluble triply‐responsive homopolymers of N,N‐dimethylaminoethyl methacrylate (DMAEMA) containing an azobenzene moiety as the terminal group were synthesized by atom transfer radical polymerization (ATRP) technique. The ATRP process of DMAEMA was initiated by an azobenzene derivative substituted with a 2‐bromoisobutyryl group (Azo‐Br) in the presence of CuCl/Me6TREN in 1,4‐dioxane as a catalyst system. The molecular weights and their polydispersities of the resulting homopolymers (Azo‐PDMAEMA) were characterized by gel permeation chromatography (GPC). The homopolymers are soluble in aqueous solution and exhibit a lower critical solution temperature (LCST) that alternated reversibly in response to Ph and photoisomerization of the terminal azobenzene moiety. It was found that the LCST increased as pH decreased in the range of testing. Under UV light irradiation, the trans‐to‐cis photoisomerization of the azobenzene moiety resulted in a higher LCST, whereas it recovered under visible light irradiation. This kind of polymers should be particularly interesting for a variety of potential applications in some promising areas, such as drug controlled‐releasing carriers and intelligent materials because of the multistimuli responsive property. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2564–2570, 2010 |
| |
Keywords: | atom transfer radical polymerization (ATRP) azo polymers azobenzene lower critical solution temperature photoresponsive pH‐responsive single‐electron transfer living radical polymerization stimuli‐responsive polymer stimuli‐sensitive polymers thermoresponsiv water‐soluble polymers |
|
|