| Shape memory polymer and its composite materials have the characteristics of lightweight,low cost,large deformability,diverse driving types and adjustable thermal transition temperature,showing great application prospects in the aerospace field.Bisphenol E cyanate ester and polybutadiene epoxy resin were co-cured to prepare CE/EHTPB shape memory resin system.SiO2@MWCNT nanocomposite filler was prepared by sol-gel method,which was used to strengthen and toughening CE/EHTPB shape memory resin system.To meet the requirements of aerospace structural materials,shape memory composites were further prepared by compounding two resin systems with carbon fiber plain weave fabric.（1）The curing temperature of CE/EHTPB shape memory resin system is lower than that of CE monomer.The initial thermal decomposition temperature of CE/EHTPB shape memory resin system is above 325℃,and the water absorption rate is less than 1.612%,showing good thermal stability and moisture resistance.With the increase of EHTPB content,the toughness of CE/EHTPB shape memory resin system increases,while the tensile strength,Young’s modulus and bending strength decrease,and the elongation at break and impact strength increase.The glass transition temperature of CE/EHTPB shape memory resin system can be adjusted in the range of 164℃to 259℃.After ten cycles of testing,the shape fixity ratio and shape recovery ratio of CE/EHTPB shape memory resin system are both above 97.5%.（2）The dispersibility of SiO2@MWCNT nanofillers prepared by sol-gel method is improved.The addition of SiO2@MWCNT has no obvious effect on the heat resistance of SiO2@MWCNT/CE/EHTPB shape memory composites,but can reduce the water absorption and enhance the strength and toughness of shape memory composites.When the content of SiO2@MWCNT is 0.9 wt%,the mechanical properties of the composites are the best.After ten cycles of testing,the shape fixity ratio and shape recovery ratio of the shape memory composite are both above 98%.（3）CF/CE/EHTPB and CF/SiO2@MWCNT/CE/EHTPB show better moisture resistance than that of pure resin.The mechanical properties of both are excellent,with tensile strength of 675 MPa and 765 MPa,Young’s modulus of 43 GPa and 47 GPa,flexural strength of 817 MPa and 875MPa,flexural modulus of 45 GPa and 48 GPa,and shear strength of 49MPa and 56 MPa.After ten cycles of testing,the shape fixity ratio and shape recovery ratio of both remained above 96%and 97%,respectively,and the recovery time was 41 s and 35 s,respectively. |
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