Analysis of thermal‐active bending and cyclic tensile shape memory mechanism of UHMWPE/CNT composite

Abstract The exploitation of shape memory ultra‐high‐molecular‐weight polyethylene (UHMWPE) can expand the application field as an intelligent material; however, low shape recovery ratio limits its further practical application. Herein, carbon nanotubes (CNT) are used to improve shape memory property of UHMWPE. Interestingly, after analyzing the bending and cyclic tensile shape memory properties of UHMWPE/CNT composite, it is found that bending shape memory property of UHMWPE/CNT composite is improved dramatically, while cyclic tensile shape memory property is not. The optimal bending shape memory property with shape fixity ratio of more than 95% and shape recovery ratio of about 94% can be obtained at 115°C. However, the shape recovery ratio in cyclic tensile shape memory test is only changed from 62.72% to 65.63%, and the shape fixity ratio is reduced from 85.82% to 82.83%. The main reason for this phenomenon is the possible difference in thermal‐active bending and cyclic tensile shape memory mechanism: CNT engender forced deformation in bending shape memory, while it does not exhibit in cyclic tensile shape memory. The outstanding bending shape memory property of UHMWPE/CNT composite make it possible for more promising applications.