【摘要】 以丙烯酸六氟丁酯(HFBA)为疏水单体、N-异丙基丙烯酰胺(NIPAM)为亲水单体、偶氮二异丁腈(AIBN)为引发剂、S,S′-二(α,α′-甲基-α″-乙酸)三硫代碳酸酯为链转移剂,采用可逆加成-断裂链转移聚合法(RAFT)合成系列温敏性两亲三嵌段聚合物PNIPAM-PHFBA-PNIPAM,采用透光率法测定其温敏性、表面张力法测定其自组装性能,以苏丹红Ⅵ作为模型药物研究PNIPAM-PHFBA-PNIPAM胶束的载药性能。研究结果表明,由于含氟嵌段的引入,合成的两亲共聚物保持了良好的温敏性,低临界相转变温度(LCST)最高达33.5℃。聚合物易发生微相分离,能在较低浓度下自组装为稳定均匀的纳米级胶束,临界胶束浓度(CMC)在0.006 mg/mL左右。胶束具有良好的药物负载能力。更多还原

【Abstract】 A series of well-defined thermosensitive triblock copolymers PNIPAM-PHFBA-PNIPAM were prepared. The copolymers consisting of two blocks of PNIPAM and one block of PHFBA at different ratio were synthesized via reversible addition-fragmentation chain transfer(RAFT) polymerization. The structures of the copolymers were characterized by ~1H-NMR. The thermosensitivity of the polymers was determined by transmittance method and the self-assembly properties were studied by surface tension method. The results show that the synthesized amphiphilic copolymers maintain the good thermosensitivity and the lower critical solution temperature is as high as 33.5 ℃. The copolymers could self-assemble into stable and uniform nano micelles at the low concentration of about 0.006 mg/mL because of the introduction of fluorine-containing blocks. The micelles have the good drug loading capacity.更多还原