【摘要】 为获得高韧性环氧树脂,合成了异氰酸酯封端的聚氨酯预聚体,用两端含羟乙基的直链有机硅(PDMS)和二羟甲基丙酸(DMPA)进行扩链改性,得到羟基封端的有机硅改性的含羧基的聚氨酯齐聚物,用此齐聚物作为增韧剂去接枝改性环氧树脂,然后用甲基四氢苯酐进行固化,得到了聚氨酯(PU)/环氧树脂(EP)互穿聚合物网络。用红外光谱和扫描电镜研究了互穿聚合物网络形成的动力学和微相分离行为;用动态力学分析和摆锤冲击实验等考察了不同配比下IPN的力学性能;用热失重分析研究了材料的耐热性。结果表明:PU/EP在一定的配比范围内可以得到冲击强度、模量及耐热性同时得到提高的复合材料。更多还原

【Abstract】 Firstly isocyanate group-terminated polyurethane prepolymer was synthesized by a re-action of a N210with Toluene-2,4-diisocyanate(TDI)and then extended with PDMS and dimethlopropionic acid(DMPA),hydroxyl group-terminated PDMS-modified polyurethane oligomers containing carboxyl groups were obtained.Subsequently,a noveltype of PU/EP IPN was prepared by reaction the oligomers with the epoxy resin,cured by methyl tetrahydrophthalic anhydride(MeTHPA).The kinetics of IPN formation and behavior of microphase separation were analyzed by FTIR and SEM.The mechnical properties with varied PU/EP ratio IPN were investigated by DMA and Izod Impact Strength,heat resistance was also studied by TGA.The experimental results show that at a certain ratio of PU/EP,the synergism of IPN occurred,accordingly the composite ma-terials obtained exhibited excellent compositive properties.更多还原