Study On Properties Of High Temperature Resistant Shape Memory Epoxy Resin Matrix Composites

The shape memory epoxy resin matrix composite is an ideal material for space deployment structures.And the research of high performance epoxy resin matrix has becoming increasingly popular.Due to the shortcomings of the general epoxy resin,such as high brittleness and insufficient heat resistance,its application is limited.In this paper,a series of novel high performance shape memory epoxy resins were prepared by introducing phthalein Cardo structure into molecular chains.A novel phthalide-containing aromatic amine(PBMI-DDE)was synthesized and five kinds of DGEBA/PBMI-DDE/DDE resin systems were prepared with the PBMI-DDE/DDE blends in different molar ratios as curing agents.The curing behavior,thermal and mechanical properties,and shape memory performance of the cured resins were characterized and analyzed in detail.The results show the initial decomposition temperature increases while the glass transition temperature is reduced as PBMI-DDE content increases.The flexural strength and impact strength of the cured compounds increase first and then decrease with the proportion of PBMI-DDE,and the epoxy resin with an equal molar ratio of PBMI-DDE/DDE has a maximum mechanical strength.The shape memory performance of these fully cured epoxy networks is improved with PBMI-DDE content.The shape recovery ratio of each system is above 96%,and the shape fixity ratio is about 95%.A novel glycidylamine epoxy resin containing phthalide Cardo structure(TGMP)was synthesized using a three-step procedure.The curing kinetics of TGMP/MNA/EMI-24 resin system was studied by differential scanning calorimetry,combined with Friedman method and model fitting analysis.It is proved that the autocatalytic kinetic equation can be used to describe the curing reaction of TGMP/MNA/EMI-24 resin system.Dynamic mechanical analysis showed that the TGMP/MNA/EMI-24 resin system has excellent heat resistance and the glass transition temperature is up to 345 °C.The comprehensive mechanical properties of carbon fiber reinforced composites are excellent.Multiple thermal cycle tests show that the material has good shape memory performance with the shape fixity ratio above 95%.