基于氨基酸-N-羧基-环内酸酐开环聚合诱导自组装制备多肽基双嵌段共聚物胶束

Synthesis of well-defined polypeptide-based diblock copolymer nanomicelles via amino acid-N-carboxyl-cyclic anhydride ring-opening polymerization-induced self-assembly

采用氮氧稳定自由基聚合方法(NMP)合成了一系列不同相对分子质量的端氨基聚苯乙烯(PS-NH2),并以其为大分子引发剂进行氨基酸-N-羧基-环内酸酐开环聚合诱导自组装(NCA-PISA),合成了结构明确的两亲性双嵌段共聚物并制备了不同形貌的纳米粒子。通过动态光散射、原子力显微镜研究了嵌段共聚物的自组装行为。研究结果表明,体系固含量和链段比例对聚合物纳米粒子形貌具有重要影响,固含量由10%增加到20%时,聚合物纳米粒子的形貌由球状转变为针状;保持固含量20%不变,大分子引发剂的聚合度由20增加到50,纳米粒子的形貌又从针状转变为球状。

Amine-terminated polystyrenes(PS-NH 2)with different molecular weights were synthesized by nitroxide-mediated radical polymerization(NMP),which were then used as the macromolecular initiator for ring-opening polymerization of amino acid-N-carboxyl-cyclic anhydride(NCA-PISA)to give well-defined amphiphilic diblock copolymers and nano-micelles with different morpholog through self-assembly.Dynamic light scattering and atomic force microscopy were used to study the self-assembly behavior of block copolymers.The results showed that the content of solid and ratios of chains exhibited obvious influence on the morphology of nanomicelles.With increasing the solid content from 10%to 20%,the morphology of nanomicelles was changed from spherical to needle-like.With the polymerization degree of the macromolecular initiator increasing from 20 to 50,the morphology of the nanomicelles changed from needle-like to spherical.