PHB 及 mPEG-PHB 嵌段共聚物的合成与表征

摘要

以β-丁内酯（BL）为单体、萘钾-冠醚为引发剂通过阴离子开环聚合合成聚（β-丁内酯）（PHB），研究了反应时间对 PHB 分子量的影响。在萘钾-冠醚引发体系的基础上制备聚乙二醇甲醚-钾大分子引发剂（mPEG-K），采用 mPEG-K 引发β-丁内酯开环聚合合成两亲性嵌段共聚物聚乙二醇甲醚-聚（β-丁内酯）（mPEG-PHB），并通过1 HNMR、FTIR、DSC 对其进行表征。通过分子自组装技术制备了 mPEG-PHB 共聚物的纳米粒子，采用 SEM、TEM、DLS 对纳米粒子进行表征。结果表明，在一定时间内 PHB 的分子量随反应时间的延长而增大。DSC 结果表明，无定形的 PHB 明显降低了结晶性 mPEG 的结晶能力。mPEG-PHB 纳米粒子为粒径在100 nm 左右的具有核壳结构的纳米微球。%Usingβ-butyrolactone(BL)as monomer,naphthalene potassium-crown ether as initiator,poly(β-butyrolactone)(PHB)was synthesized by anionic ring-opening polymerization.The effect of reaction time on molecular weight of PHB was studied.Poly(ethylene glycol)methyl ether-potassium macroinitiators(mPEG-K) was synthesized based on naphthalene potassium-crown ether.Amphiphilic poly(ethylene glycol)methyl ether-poly(β-butyrolactone)(mPEG-PHB)was prepared by ring-opening polymerization of BL initiated by mPEG-K. Copolymer was characterized by 1 HNMR,FTIR,DSC.The copolymer nanoparticles were prepared by the mo-lecular self-assemble technology.These nanoparticles were characterized by SEM,TEM,DLS.The results showed that the molecular weight of PHB increased with reaction time in a certain time.The DSC results showed that amorphous PHB reduced the crystallization ability of mPEG significantly.These nanoparticles were core-shell structure nanospheres with size of 100 nm.