新型聚六氢三嗪树脂的设计合成及其在可循环回收碳纤维增强复合材料的应用

Carbon fiber reinforced thermosetting resin matrix advanced composite materials demonstrate good comprehensive properties and are widely used in high-tech fields. However, their recycling process easily encounters such followed difficulties: surface damage of carbon fiber, fiber and fiber bundle arrangement disorder, damage of their braided structures, unrecyclable matrix, etc. With the aim to solve these bottleneck problems starting from the source, this project intends through the green design to synthesize novel poly(hexahydrotriazine) thermosetting resins, make them possess the advantages of high performance, long life and easy recycling etc. After the resins combining with carbon fibers to manufacture of composite materials, it can realize to controllably completely degradate and recover the main raw materials (aromatic amines) under special conditions by utilizing the acid-catalyzed hydrolysis property of this hexahydrotriazine carbon-nitrogen heterocyclic structure, then carbon fibers can be undamagely recovered and the whole composite materials can recycle and reuse. It will study systematically the resin molecular design, synthesis mechanism and methods, curing process, interface processing and composite material preparation technology, the resin depolymerization mechanism, depolymerization kinetics, etc and establish the green recoverd process route of the advanced composite materials. Their safety use range will be determined and the contradiction between the use stability and recycling will be solved. The theoretical design framework and application technology of recyclable advanced composite materials will also be illuminated. This project has the advantages of novel design, reasonable research contents, feasible technology route and solid preliminary work basis. So, it will be able to provide scientific basis for improving advanced composite materials' comprehensive performance, prolonging their service life and endowing their environmental friendliness.

针对碳纤维增强热固性树脂基先进复合材料废弃物回收过程中，容易导致纤维表面受损、扰乱丝束排列秩序、破坏编织结构等问题，本项目拟从源头出发，通过绿色化设计，合成新型聚六氢三嗪树脂，使之兼具高性能、长寿命和易于循环回收等优点；该树脂与碳纤维复合后，可利用其结构中六氢三嗪碳氮杂环在特殊条件下的酸催化水解特性，实现基体合成主要原料的可控全降解和回收，进而无损回收碳纤维，循环利用整体复合材料。将系统研究树脂分子设计、合成机理和方法、固化工艺、界面处理、复合材料制备技术、树脂解聚机理、解聚动力学等，建立先进复合材料绿色回收再利用工艺路线，明确其安全使用范围，平衡材料可循环回收利用与使用稳定性之间的矛盾，阐明可循环回收利用的复合材料设计理论框架和应用工艺。本项目构思新颖，研究内容设置合理，技术路线可行，前期工作基础扎实，将能为提高纤维复合材料综合性能、延长使用寿命且赋予其环境友好性提供科学依据。

碳纤维增强热固性树脂基先进复合材料废弃物回收过程中，容易出现纤维表面受损、扰乱丝束排列秩序、破坏编织结构等问题，本项目从源头出发，通过绿色化设计，合成了一类含有新型动态共价键结构的聚六氢三嗪树脂和全芳香结构聚亚胺树脂，使之兼具高性能、长寿命和易于循环回收等优点；该类树脂与碳纤维复合后，利用其结构中六氢三嗪碳氮杂环和芳香亚胺键在特殊条件下的酸催化水解特性，实现了基体合成主要原料的可控全降解和回收，进而无损回收碳纤维，循环利用整体复合材料。系统研究了树脂分子结构设计、合成机理和方法、固化工艺、界面处理、复合材料制备技术、树脂解聚机理、解聚动力学等，深入探讨了树脂结构对憎水、导热、耐热、力学等性能的影响规律和作用机制。研究发现所制备树脂均具有良好的耐酸、碱、盐、油、氧化剂、溶剂等化学药品性能，通过调整酸性降解溶液溶度参数、提高降解溶液在树脂表面浸润效果，可实现树脂在较温和条件下的快速降解。建立了先进复合材料绿色回收再利用工艺路线，测定了复合材料耐化学药品性能，明确了其安全使用范围，平衡了材料可循环回收利用与使用稳定性之间的矛盾，阐明了可循环回收利用的复合材料设计理论框架和应用工艺。采用本项目技术路线所制备的复合材料，具有优异的力学、耐热、耐化学药品等性能，且通过较温和回收工艺，可以无损回收碳纤维和基体树脂主要合成原料。本项目构思新颖，研究内容设置合理，技术路线可行，为提高纤维复合材料综合性能、延长使用寿命且赋予其环境友好性提供了科学依据。