Block copolymers containing poly(aryl ether ketone) unit and different lengths of thermotropic liquid crystalline polyesters(TLCP) segments were synthesized by high temperature solution polymerization. The chemical structure, thermal properties and liquid crystalline behavior of the block copolymers were investigated by FTIR, DSC and PLM respectively. A single glass transition revealed that the two blocks had good a compatibility. The length of TLCP segment had a significant influence on the copolymers′ liquid crystalline behavior. When the molecular weight of TLCP reduced to 2965, liquid crystallinity of copolymer disappeared. The block copolymers showed a typical nematic threaded texture which differed from polyester′s.
以卟啉衍生物为内核,采用可逆加成-断裂链转移(RAFT)聚合法合成了温度敏感性聚己内酯-聚N-异丙基丙烯酰胺。用FT-IR、1 H NMR、GPC、TEM、分子荧光、变温紫外、粒度分布等手段对聚合物进行了表征,并以紫杉醇为模型药物分子,进行了药物释放测试。结果表明,聚合物自组装后,形成了平均直径为100nm左右的胶束。这种内部亲脂外部亲水的核壳结构能够稳定地载药,在温度为15℃的DMF中,12h内释放了37%的药物,而在温度为38℃的DMF中,12h药物释放量为81.4%。这种两亲性大分子聚合材料对紫杉醇的释放具有温度敏感性,有望在抗癌药物的控制释放领域得到广泛应用。
