高回复力低密度新型航天高温形状记忆材料

Recovery stress is crucial for the shape memory materials during function and the low recovery stress of shape memory polymer(SMP)limits their practical applications greatly, whereas the shape memory alloy(SMA)with high recovery stress needs complex and difficult processing technology. Herein, the shape memory polyimide with high recovery stress(SMPI-HRS)is easily prepared by reinforcing SMPI with carbon fiber cloth, and it possesses recovery stress of 130 MPa, glass transition temperature of 303 ℃ and low density of 0.98×10³ kg/m³. Its recovery stress is comparable to those of some high temperature shape memory alloys(HTSMA)and far higher than those of other SMPs, meantime its density is less than one sixth of that of HTSMA. The SMPI-HRS can overturn metal sheet about 170 times heavier than its own weight during shape recovery, and it has great potentials in a broad range of applications such as high temperature adapter sleeve, automatic tail bolt and elastic wings.