聚氨酯改性三官能团环氧树脂的性能

Properties of Polyurethane Modified Trifunctional Epoxy Resin

采用4,4'-二苯基甲烷二异氰酸酯(MDI)和聚乙二醇(PEG)为原料,制备端异氰酸酯基聚氨酯(PU)预聚体,用该预聚体对已合成的三官能度环氧树脂(TEP)进行改性。通过红外光谱分析(FT-IR)、扫描电镜(SEM)、热重分析(TG)和动态热力学分析(DMA)表征了交联物(TEP-PU)的基团变化、断面形貌、热性能和动态性能。研究表明:PU链段成功连接到TEP分子链上;当m(PU)∶m(TEP)=5%时,TEP-PU固化物的巴氏硬度为41.4HBa,冲击强度为23.32kJ/m2,玻璃化转变温度有明显提升,改性的TEP断面呈现韧性断裂。

4, 4＇-diphenylmethane diisocyanate （MDI） and polyethylene glycol （PEG） were used as raw materials for synthesis of isocyanate terminated polyurethane （PU） pre-polymer. Then, PU pre-polymer was used to graft trifunctional epoxy resin （TEP） which was synthesis in lab to obtain cross-link TEP-PU. Fourier Transform Infrared spectroscopic analysis （FT-IR） , Scanning Electron Microscope （SEM）, Thermogravimetric analysis （TG） and Dynamic Analysis of thermodynamics （DMA） were used to study postcured of TEP-PU groups changing, morphology thermal properties and dynamic mechanical properties respectively. Results indicated that PU chain grafted onto the TEP chain successfully. When rn（PU） ： m（TEP） was 5%, the Barcol hardness was 41.4 HBa, impact strength was 23.32 kJ/m^2 , glass transition temperature was obviously improved, section of modified TEP presented ductile fracture.