杂化共聚制备新型生物可降解高分子及其应用

Biodegradable polymer is widely applied to biomedical, agricultural and packaging, which is one of promising strategies to solve environmental pollution by waste polymer. This project intends to synthesize novel biodegradable polymer by hybrid copolymerization of cyclic esters with vinyl monomers, namely one-step insertion of biodegradable ester bond into polymer main chain. We will examine the mechanism of hybrid copolymerization catalyzed by phosphazene；optimize the polymerization conditions to achieve controlled hybrid copolymerization; synthesize polyester copolymers containing pendant functional groups, such as carboxylic acid, hydroxyl and amine, by the hybrid copolymerization of cyclic esters with related functional vinyl monomers and study their degradation properties; we will also synthesize cationic polymeric vector containing ester bond in its main chain and study its cytotoxicity and gene tranfection efficiency. By means of in-depth investigation of the possibility of hybrid copolymerization of cyclic esters with vinyl monomers, it will expand the scope of hybrid copolymerization and offer unique methods for the preparation of novel biodegradable polymer and functional polyesters.

生物可降解高分子可应用于生物医学﹑农业和包装材料，是解决废弃高分子材料污染的最佳途径。在本项目中，我们将通过磷腈催化环酯类单体与乙烯基单体的杂化共聚制备新型生物可降解高分子，即一步法将可降解的酯键嵌入高分子主链。研究磷腈催化杂化共聚的机理，优化聚合条件实现可控杂化共聚；通过环酯类单体与含官能团乙烯基单体的共聚制备含羧基﹑羟基和胺基等功能性侧基的聚酯共聚物并研究其降解性能；研究主链含酯键的阳离子高分子载体的细胞毒性及基因转染效率。通过深入研究各种环酯与乙烯基单体进行杂化共聚的可能性，可扩展杂化共聚的应用范围，从而为合成新型生物可降解高分子和功能性聚酯提供新途径。

生物可降解高分子可应用于生物医学﹑农业和包装材料，是解决废弃高分子材料污染的最佳途径。本项目预期是通过磷腈催化环酯类单体与乙烯基单体的杂化共聚制备新型生物可降解高分子，即一步法将可降解的酯键嵌入高分子主链。在本课题的资助下，我们系统研究了磷腈催化己内酯(CL), 丙交酯(LA), 乙交酯(GA)和三亚甲基碳酸酯(TMC)等环酯类单体与含功能性基团乙烯基单体甲基丙烯酸N,N-二甲基胺基乙酯(DMAEMA)的均聚和共聚反应研究。基于磷腈催化聚合的结果，我们还研究了路易斯酸催化剂三(五氟苯基)硼烷(B(C6F5)3)催化己内酯(CL)，环酯类单体及乙烯基单体的均聚和共聚。此外，我们还合成了新型共聚物并研究了其在多相乳液（multiple emulsions）中的应用。对于CL与DMAEMA的杂化共聚物，我们发现随CL含量的增加能显著降低共聚物的细胞毒性而不降低基因转染效率。我们还发现B(C6F5)3可以催化β-丁内酯与苯乙烯的杂化共聚。