基于Diels-Alder反应的热可逆交联聚醚胺的制备和表征

Preparation and Characterization of Thermal Reversible Polyetheramine Based on Diels-Alder Reaction

首先利用聚乙二醇缩水甘油醚(PEG-DE)、乙二醇二缩水甘油醚(EG-DE)与呋喃甲胺(FMA)进行预聚反应,合成了分子链上含有呋喃基团的聚醚胺预聚物(Pre-PEA),然后采用DielsAlder反应,以双马来酰亚胺(BMI)交联该聚醚胺预聚物,制得交联聚醚胺(PEA)。通过拉伸测试系统地分析了PEA的力学性能及其影响因素。结果表明,经过对分子链结构的设计及交联密度的调节,PEA的性能完成了从"软而韧"到"强而韧"的转变。制得的PEA具有很好的自修复性能,表面裂痕可以在120℃以下完全自修复。采用超声重塑法与热压重塑法对制得的PEA进行重塑加工,2次重塑后其断裂强度至少能达到原始样品的70%,断裂伸长率至少能达到原始样品的80%。

Polyethyleneglycol diglycidyl ether(PEG-DE)and ethyleneglycol diglycidyl ether(EG-DE)were used to react with 2-furylmethylamine(FMA)to synthesize a series of prepolymers of polyetheramines(Pre-PEA)grafted with furan groups.With Bismaleimide(BMI)as the crosslinking agent,a series of polyetheramine(PEA)samples were synthesized via Diels-Alder reaction.The mechanical properties of PEA samples and the influence factors were studied by a series of tensile measurements.It was shown that the chain structure and crosslinking density could have significant impacts on the mechanical performances of the PEA.As the two factors changed,PEA changed from flexible to rigid,equipping the PEA with outstanding thermal plastic reprocessing ability.Self-healing tests were conducted on the PEA samples to discuss the range of the healing temperature during the self-healing process.When the temperature was raised up to 120℃,the cracks on the surfaces of the samples were recovered.Importantly,the reversible Diels-Alder reaction endued the remolding and self-healing abilities to the PEA.Two remolding approaches were conducted and studied in this system.The mechanical properties of the regenerated PEA were studied by a series of tensile measurements.After remolding for two generations,the regenerated PEA sample maintained above 70%of the original breaking strength and above 80%of the original the elongation at break.To be concluded,this series of PEA samples exhibited great performance on self-healing and remolding properties.