pH值响应性超支化多臂共聚物的合成及其自组装行为研究  

SYNTHESIS AND SELF-ASSEMBLY OF A pH-SENSITIVE HYPERBRANCHED MULTIARM COPOLYMER

作　　者：钟玲[1] 贺小华[2] 周永丰[1] 颜德岳[1] 潘才元[3] 

机构地区：[1]上海交通大学化学化工学院,上海200240 [2]华东师范大学化学系,上海200062 [3]中国科学技术大学高分子科学与工程系,安徽230026

出　　处：《高分子学报》2007年第10期986-992,共7页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号50503012;50633010);国家重点基础研究发展计划(项目号2005CB623803;2007CB808000)资助项目

摘　　要：以超支化双硫酯为链转移剂,偶氮二异丁腈(AIBN)为引发剂,采用可逆加成-断裂链转移(RAFT)活性自由基聚合方法,合成了以超支化聚酯(Boltorn H20)为核,聚丙烯酸为臂的两亲性超支化多臂共聚物(H20-star-PAA),并通过紫外分光光度计、动态光散射(DLS)和透射电子显微镜(TEM)对它在水溶液中的pH响应的自组装行为进行了研究.结果表明,在稀溶液条件下,H20-star-PAA始终以单分子胶束的形式存在,随着溶液pH的降低,胶束的PAA壳层会逐步塌缩,导致胶束尺寸减小;而在浓溶液条件下,当溶液的pH较低时,单分子胶束会进一步聚集形成多分子胶束.Reversible addition-fragmentation fractionated hyperbranched polyester （Bolton transfer （RAFT） polymerizations H2O） based macroRAFT agent of acrylic acid were conducted using to obtain a hyperbranched multiarm copolymer of H2O-star-PAA. Phase transition and serf-assembly behavior of H2O-star-PAA at different solution pH were also studied by using dynamic light scattering （DLS） and transmission electron microscopy （TEM）. The results show that at lower polymer concentrations, the hyperbranched macromolecules exist as unimolcular core-shell nanostructures with hydrophobic BoltornH2O as the core and swollen poly（acrylic acid） （PAA） as the shell, and the PAA shells will collapse on the surface of the micelles with decreasing the solution pH. While in high concentrations of the polymer, H2O-star-PAA self-assemble into large multimolecular micelles due to the secondary aggregation of unimolecular micelles stabilized by the intermolecular hydrogen bonding.

关 键 词：可逆加成-断裂链转移 超支化 丙烯酸 自组装 

分 类 号：O631.3[理学—高分子化学]