MULTI-PERFORMANCE SHAPE MEMORY EPOXY RESINS AND THEIR COMPOSITES WITH NARROW TRANSITION TEMPERATURE RANGE

Shape memory epoxy resins are one of the most widely used engineering intelligent polymers, mainly used in aerospace, intelligent bionics, and other fields of active deformation structures. A series of shape memory epoxy resins with a narrow transition temperature range, showing strong inter-segment forces and regular uniform cross-linked networks are designed and synthesized. By adjusting the stoichiometry and cross-linking density, the length of the segments is uniformly controlled. The glass transition temperature range can reach 14-23°C, which improves the efficiency of shape memory action. Besides, the multi-amines crosslinking agents were used to adjust the distribution of the chain segment to achieve the effect of adjusting Tg. Moreover, the addition of epoxy-terminated liquid nitrile rubber (ETBN) composites can toughen the system. The elongation at break can be increased up to 4 times. Furthermore, combing the two-stage curing method, and add the nano-particle high-temperature latent curing agent based on the ETBN toughening system, the super curing effect is achieved, Tg, modulus and strength of composites are improved. The resulting composites are appropriate for shape fixation and recovery temperature with more precision and closer distance between, which can meet the higher requirements of the aerospace field.