基于硒醚取代环状内酯的多功能集成聚酯合成

Aliphatic polyester has received great attention in recent years because of its good biocompatibility, good mechanical properties, and excellent biodegradability through hydrolysis as well as enzyme catalytic degradation. However, because of the hydrophobic and semi-crystalline nature, low degradability, and especially the lack of functional groups, its biomedical applications are limited. As the result, the introduction of functional groups into these polyester chain is one of hot topic in this fields for the aim of such as increasing the hydrophilicity, adjusting the degradation rate, decreasing the crystallinity etc. Different kinds of reactions have been developed to realize such modification. Typical reactions such as Baeyer-Villiger oxidation, electrophilic substitution reaction, and hybrid polymerization etc. However, the rigid reaction conditions and limited functional groups for one reaction are far from enough for developing high performance materials. .With such situation in mind, the aim of this proposal is focused on developing novel way to solve such difficulty by introducing selenide contained structures onto lactone. Using such selenide-functionalized lactone as novel "synthesis", multifunctional groups could be integrated with polyester main chain through the unique chemical reaction of selenide combining with the click chemistry and hybrid polymerization methods. The current method shows advantages as following: 1) versatile functionalization abilities could be derived from one simple selenide functionalized lactone monomer by adjusting reaction conditions; 2) mild reaction conditions would be favored for non-disturbing sensitive ester structure within main chain of polyester, which could avoid the possible degradation during modification; 3) by the combination of efficient reactions, such as Click reaction and controlled radical polymerization, it offered the ability for synthesis polymers with controlled structures. These advantages would be valuable for developing versatile functional polyester with controlled structures adjustable properties.

本项目针对目前PCL类聚酯存在结构单一，难以实现多功能集成的难题，利用含硒化合物具有的独特化学反应，设计合成含有苯基硒醚功能化的内酯单体，探索将该单体作为“合成子”，结合点击化学、杂化聚合等方法，开展含有功能性基团聚酯结构的可控合成研究，实现聚酯材料的功能集成，为该类聚合物的应用提供灵活、便利的合成方法。与现有改性方法相比，本项目拟采用的方法具有以下优点：1）功能化方式丰富，可以由一种苯基硒醚功能化内酯出发，通过不同的反应途径获得丰富功能化集成的聚酯材料；2）反应条件温和，对主链中敏感的酯基影响甚微，最大程度避免了功能集成过程中可能存在的主链降解问题；3）改性过程中充分运用当前高分子合成中的新型高效反应，对聚合物结构具有优异的可控性，可以实现聚合物的合成设计。

项目针对目前PCL类聚酯存在结构单一，难以实现多功能集成的难题，利用含硒化合物具有的独特化学反应，设计合成含有苯基硒醚功能化的内酯单体，探索将该单体作为“合成子”，结合活性聚合方法，开展含有功能性基团聚酯结构的可控合成研究，实现聚酯材料的功能集成，为该类聚合物的应用研究提供灵活、便利的合成方法。.通过项目的实施，完成了项目预定研究任务，主要取得了以下创新成果：1）探索和建立了硒醚功能化己内酯化合物的便利合成方法，并建立了功能化聚酯的可控合成。利用二苯基二硒醚等常见化合物作为起始原料，通过亲核反应，简便高效的实现了硒醚功能化己内酯的制备。进一步通过优化聚合条件，实现了分子量分控，分子量分布指数窄的功能性聚酯的可控合成。利用硒醚功能基团的氧化还原特性，开展了具有双键、不同侧基和不同主链结构的功能性聚酯的合成。2）探索了硒醚功能化聚酯在抗菌、药物缓释和催化聚合反应等方面的应用。首先通过将聚酯所含的硒醚侧基进行硒鎓离子化，作为抗菌聚合物材料，探索了不同对离子、侧基结构和亲水亲油基团比例等参数与材料抗菌性能的关系，创新构建了最低抗菌浓度可抵达1微克每升的高效含硒可降解抗菌聚合物材料。该材料不仅抗菌浓度低，而且其聚己内酯主链结构赋予材料优异的生物相容性和降解性，为抗菌高分子材料提供了新的思路。其次该类材料还可以催化乙烯基醚的活性阳离子聚合。3）利用硒醚功能聚合物的独特响应性，合成了系列不同结构的功能聚合物，用于光子晶体的制备，实现了折光指数响应的光子晶体构筑，可用于硝基化合物等氧化性物质的检测中。项目研究结构发表研究论文18篇，授权发明专利12件，培养研究生9名。