脂肪族聚酯vitrimer动态交联网络的构建和流变性能的研究

Vitrimer based on dynamic covalent bonds is a new polymer material, which combines the advantages of thermosetting polymers with covalently cross-linked networks and thermoplastic polymers that can be reprocessed. It has attracted great interest in the field of polymer chemistry and new polymer development. Although aliphatic polyesters have attractive biocompatibility and biodegradability, the poor mechanical properties and thermal stability have limited their application as medical polymer. Based on the good performance of vitrimer and intrinsic advantage of aliphatic polyesters in vitrimer preparation, the project introduce dynamic covalent bonds into the cross-linked network of polyesters to develop novel polyester vitrimer with dynamic cross-linked topological structure, aiming to enhance the mechanical and processing performance. Despite the covalent network, vitrimer still can be reprocessed. The curing kinetics, viscoelastic properties, thermal properties and mechanical properties of vitrimer can be adjusted by changing the functional groups in the reactants, catalysts and synthesis methods and so on. In addition, this project not only provide a new method for the modification of aliphatic polyesters, but also reveal the characteristic viscoelastic properties of vitrimer under dynamic shearing by studying the rheological properties of polyester vitrimer. The project will provide theoretical foundation and experimental basis for the development of aliphatic polyester vitrimer with high performance.

基于动态共价键的vitrimer是一种新兴的高分子材料，它兼具热固性聚合物的交联网络结构和热塑性聚合物可再加工的特点，在聚合物改性和新材料研究中引起广泛的关注。脂肪族聚酯具有良好的生物相容性和生物可降解性，但其机械性能和热稳定性的不足限制了其作为医用高分子材料的应用。本项目结合vitrimer优良的性能和脂肪族聚酯制备vitrimer的优势，在聚酯的交联网络中引入动态共价键，形成具有动态交联网络结构的脂肪族聚酯vitrimer，在改善性能的同时仍赋予其可再加工性。通过改变催化剂、交联剂、合成方法以及反应物官能团修饰来精准调控vitrimer的粘弹性能、热性能和机械性能等。结合脂肪族聚酯vitrimer线性和非线性流变性能的研究，构建交换反应动力学和材料流变性能之间的调控机制，揭示vitrimer的流变指纹特征，为高性能脂肪族聚酯vitrimer的研发和加工提供理论依据和实验基础。

基于动态共价键的vitrimer是一种新兴的高分子材料，它兼具热固性聚合物的交联网络结构和热塑性聚合物可再加工的特点，在聚合物改性和新材料研究中引起广泛的关注。脂肪族聚酯具有良好的生物相容性和生物可降解性，但其机械性能和热稳定性的不足限制了其作为医用高分子材料的应用。本项目结合vitrimer优良的性能和脂肪族聚酯制备vitrimer的优势，在聚酯的交联网络中引入动态共价键，形成具有动态交联网络结构的脂肪族聚酯vitrimer，在改善性能的同时仍赋予其可再加工性。通过改变催化剂、交联剂、合成方法以及反应物官能团修饰来精准调控vitrimer的粘弹性能、热性能和机械性能等。结合脂肪族聚酯vitrimer线性和非线性流变性能的研究，构建交换反应动力学和材料流变性能之间的调控机制，揭示vitrimer的流变指纹特征，为高性能脂肪族聚酯vitrimer的研发和加工提供理论依据和实验基础。