硫醇-烯烃点击可控制备多功能N-P骨架超支化环氧树脂及性能

Basing on trithiol and diene monomers obtained respectively from isocyanurate and phenylphosphinyl chloride, nitrogen-phosphor backbone hyperbranched epoxy resins (NPHEP) with controllable chemical micro-structures (molecular weight, degree of branching and epoxy value) will be synthesized by Thiol-ene Click Reaction, using secondary amine dithiol and monothiol as branching and linear monomers, respectively, and using glycidyl methacrylate (GMA) as an epoxy monomer. The resulted hyperbranched epoxy resin is expected to have higher toughness, strength, flame-retardance and heat-resistantence compared to conventional diglycidyl ether of bisphenol-A (DGEBA). The degree of branching (DB) and epoxy value (EV) of NPHEP can be controlled by a ratio of branching to linear monomers and the mumber of thiol-ended respectively. Chemical structure, DB and molecular weight will be characterized by NMR, GPC, et al. Effects of NPHEP micro-structures on compatability, phase separation morphology, interfacial interaction between NPHEP and DGEBA, mechanical performance, thermal properties, and flame-retardation performance of NPHEP/DGEBA blends will also be studied. Both TG-FTIR and Cone calorimetry will be used to investigate the thermal decomposition and flame retarding mechanism of NPHEP. Through this research, a novel approach for preparing NPHEP with controllable micro-structures will be obtained. A quantitative relationship between chemical micro-structures of NPHEP and macro-performances of NPHEP/DGEBA will also be elucidated, as well as a relativity between toughening and reinforcing-toughening mechanism of hyperbranched epoxy resins. This work may serve as an important recognition, fundamental theoretical and experimental guidance for developing epoxy resins with solvent-free and high performance.

以异氰脲酸酯和磷酰氯分别制备三元硫醇和二元烯烃，二巯基、单巯基仲胺分别为支化和线形单体，甲基丙烯酸缩水甘油酯为环氧单体，基于硫醇-烯烃点击反应制备微观化学结构（分子量、支化度、环氧值）可控的具有增强、增韧、阻燃和耐热功能的低粘度N-P骨架超支化环氧树脂(NPHEP)。以支化和线形单体的比例控制支化度，端巯基数量控制环氧值。采用NMR、GPC等技术表征产物的结构、支化度、分子量等性质。研究NPHEP微观化学结构对NPHEP/双酚A型环氧树脂复合材料的相容性、相分离形貌、界面相互作用、机械性能、热性能、阻燃性能的影响规律，以热红联用技术和锥形量热仪研究NPHEP的热分解和阻燃机理。将获得微观结构可控NPHEP的制备工艺，解明NPHEP的微观结构与复合材料宏观性能的定量关系和原因，明确超支化环氧树脂增韧与增韧增强机理之间的相关性，对环氧树脂的无溶剂化、高性能化提供规律性认识和理论及实验指导。

针对超支化环氧树脂的微观化学结构难于精确控制及其增强增韧机理研究困难的关键科学问题。本项目通过硫醇-烯烃点击反应设计制备了微观化学结构（分子量、环氧值和支化度）精准可控的超支化环氧树脂，研究了微观结构对宏观性能的影响规律和原位增强增韧机理。发明了超支化环氧树脂微观结构可控的高效绿色制备关键技术，弄清了超支化环氧树脂的微观结构对其宏观性能的影响规律，对环氧树脂的绿色制备、高性能化提供规律性认识和理论及实验指导。主要研究内容如下：（1）支化度可控超支化环氧树脂的设计制备及其性能。设计合成了三巯基单体、双乙烯基磷酸酯单体、支化单体和线性单体。通过硫醇-烯烃点击反应制备了支化度可控的端羟基超支化聚合物、端巯基超支化聚合物和N-P骨架超支化环氧树脂（NPEHP-n）。实验的支化度与它们的理论设计值接近，实验测试的分子量与理论设计值也接近，证实了超支化环氧树脂的支化度和分子量精准可控。支化度对NPEHP-n/DGEBA杂化材料性能的影响研究表明，支化度高的超支化聚合物具有较高的冲击强度，支化度低的超支化聚合物具有较高的拉伸强度和弯曲强度，支化度为1的超支化环氧树脂能提高DGEBA的拉伸强度、弯曲强度和冲击强度分别为43%、76%和298%。（2）环氧值可控的超支化环氧树脂的合成及其性能。利用端羟基超支化聚合物与巯基丙酸制备巯基可控的超支化聚酯，再与烯丙基缩水甘油醚进行点击反应制备环氧值不同的超支化环氧树脂（EHBP-n）；随着EHBP-n环氧值的增加，EHBP-n/DGEBA杂化材料的机械性能先增加后降低，中等环氧值的超支化环氧树脂能提高DGEBA的拉伸强度、弯曲强度和冲击强度分别为39%、54%和208%。（3）硫醇-烯烃点击反应制备环氧树脂的新方法。设计制备了多种官能度环氧树脂和超支化环氧树脂，反应时间仅为5-10分钟，产率高于95%。