自组装制备聚(丙烯酸叔丁酯-b-甲基丙烯酸二甲胺基乙酯)壳交联胶束

以1-氯代乙苯为引发剂、氯化亚铜/N,N,N′,N″,N″-五甲基二乙撑三胺(PMDETA)为催化体系、丁酮-异丙醇为混合溶剂,通过原子转移自由基聚合法制备不同分子量的大分子引发剂聚丙烯酸叔丁酯(1-PECl)及不同嵌段比的两亲性嵌段共聚物聚(丙烯酸叔丁酯-b-甲基丙烯酸二甲胺基乙酯)(P(tBA-b-DMAEMA))。通过1H-NMR表征了P(tBA-b-DMAEMA)的结构,GPC测试了其分子量及分子量分布。P(tBA-b-DMAEMA)在选择性溶剂中自组装形成核-壳结构的胶束,引用了乙烯基乙二醇二碘醚(BIEE)为交联剂与链段PDMAEMA发生化学交联反应从而得到稳定的壳交联胶束结构,并通过马尔文粒径仪研究了自组装所得胶束的温度及pH敏感性。

Synthesis of Poly(t-butyl acrylate-b-2-dimethylamino ethyl methacrylate) and Preparation of Shell Cross-Linked Micelles via Self-assembly

Poly(t-butyl acrylate-b-2-dimethylamino ethyl methacrylate)S(P(tBA-b-DMAEMA))with different proportions of two monomers were prepared by atom transfer radical polymerization(ATRP) using 1-chlorophenylethane(1-PECI)as initiator and CuCl/N,N,N',N",N"-pentamethyldiethylenetriamine(PMDETA)as catalyst in a mixture solvent of butanone and 2-propanol.The structures of P(tBA-b-DMAEMA)were characterized by ~1H-NMR.The molecular weights and polydispersity indexes(PDI)of the block copolymers were determined by gel permeation chromatography(GPC).The amphiphilic block copolymers P(tBA-b-DMAEMA)self-assemble into micelles in a selective solvent.Shell cross-linked "knedel"(SCK)micelles were synthesized using a bifunctional cross-linker,1,2-bis-(2-iodoethoxy)ethane (BIEE).The sizes of micelles were changed with different contents of cross-linker agent,and the temperature-pH-sensitive behavior of SCK micelles were investigated by DLS.