文献类型：期刊文献

英文题名：Synthesis and Self-Assembly Behavior of Six-Armed Block Copolymers with pH- and Thermo-Responsive Properties

作者：Huang, Xiujuan[1];Xiao, Yan[1];Lang, Meidong[1]

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

年份：2011

卷号：19

期号：2

起止页码：113

外文期刊名：MACROMOLECULAR RESEARCH

收录：;EI(收录号：20111113755871);WOS:【SCI-EXPANDED(收录号:WOS:000289239100003)】；

基金：This research was supported by the Fundamental Research Funds for the Central Universities, "Shu Guang" Project of Shanghai Municipal Education Commission, Shanghai Leading Academic Discipline Project (B502) and Shanghai Key Laboratory Project (08DZ2230500).

语种：英文

外文关键词：ring-opening polymerization; atom transfer radical polymerization; self-assembly; star copolymers; cyclotriphosphazene

摘要：A series of amphiphilic six-armed copolymers, containing poly(e-caprolactone) (PCL)and poly(2-(diethylamino) ethyl methacrylate) (PDEAEMA or PDEA) as the arm and cyclotriphosphazene as the core, were obtained by a combination of ring-opening polymerization (ROP) and atom transfer radical polymerization (ATRP). The star block S(PCL-b-PDEAEMA) copolymers were characterized by H-1 NMR spectroscopy and size exclusive chromatography (SEC). These copolymers could self-assembly into micelles in an aqueous solution at low pH with a low critical aggregation concentration (CAC) in the range of 2 to 10 mg/L, which depend on the composition of the copolymers. The original aggregates could further form larger micelles and/or vesicles by adjusting the external stimulus, which was examined by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The lower critical solution temperature (LCST) of the star copolymers were determined to be 49.7 and 26.3 degrees C at pH 6.5 and 7.4, respectively, demonstrating a pH-dependent thermo-response.