| Space deployable structure technology is an effective way to construct large-scale spatial structure and reduce the spatial launch volume and the launch cost. Shape memory thermoset resin composite is the ideal material for spatial deployable structure.It can be fold on the ground and be deployed on the orbit when heating. A kind of shape memory epoxy resin was developed and its performance, shape memory mechanics and reaction condition was discussed in this research. In view of the existed problem of the prepared epoxy resin, the modification of this resin system was carried out and two-stage rigidization technology was proposed.The glass transition temperature of the resin system was characterized by differential scanning calorimeters (DSC). Fold deformation was carried on above Tg and the best resin proportion that can show shape memory effect was determined. The variation of the storage modulus and loss tangent along with the temperature for the resin system was determined by dynamic mechanics analysis (DMA). The cross-linking degree of resin system was calculated and the condition of shape memory effect existing was analyzed. The fold-deployment and the stretch-contraction shape memory testing of the resin system was carried out. The influence of cross-linking degree on shape fold strain, the influence of deformation recovery temperature on deformation recovery time and the influence of shape deform cycle-index on the shape memory property and mechanical property was discussed. The shape memory mechanism of epoxy resin was analyzed.Low molecular weight aliphatic epoxy and nano-silicon dioxide was used to modify the shape memory epoxy resin separately. The tensile performance testing indicated that the resin system yielded when the low molecular weight aliphatic was added in epoxy EPG-18. This system performed an outstanding shape memory property and scanning electricity microscope (SEM) showed it was gliding fracture. The toughness of the epoxy resin system modified with the nano-SiO2, as a result, has not effectively improved due to agglomerate of nanometer granule. The shape memory property and the inter-level the shearing strength (ILSS) of aramid fiber/epoxy shape memory composites were studied. The influence of the fiber content to the shape memory property of composites was analyzed. The result showed that the composites'shape memory property was weaken with the increases of fiber content. The best weight percent of the fiber must be controlled between 20% to 40%.The mechanics strength of shape memory epoxy resin reduces after being heated. In order to solve this problem, the UV initiation and heat initiation two-stage rigidization technology was proposed. The results showed that, for EPG-18 system, Tg was increased by 20℃, cross-linked degree was increased 6.7 times, and tensile strength was increased 95.9% after the UV two-stage rigidization. For EP-60 system, Tg was increased 107℃, cross-linked degree was increased 20.2 times, that is 6.57×10-3 mol·cm-3. It was feasible for two-stage rigidization technology to improve the thermal properties and mechanical strength of the thermosetting shape memory epoxy resin effectively.
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