Shape memory effect in polyimide-based composites with multiple driving methods

Abstract

Shape memory polymers and composites have potential in many application fields as a kind of smart materials with excellent shape memory properties. Herein, two shape memory polyimides (SMPIs) were prepared via thermal imidization process. Furthermore, shape memory composites (SMPCs) were obtained via solution impregnation and compression molding methods using SMPI as the polymer matrix and carbon plain weave fabric as the reinforcement. These polyimides and composites possessed superior shape memory behavior (shape memory recovery ratio, Rr, of SMPI 1 and HO-SMPC-40%: 99.1% and 90.6%). Remarkably, both of these samples maintained stable cyclic and bending shape memory performances. In addition, the composites were endowed with electrical-induced shape memory characteristics owing to their great conductivity. The SMPCs work effectively as deformable lightweight devices, which they could produce shape memory effect in different degrees reflecting to different applied power levels (Rr of HO-SMPC-40% under the power of 10 W and 20 W: 33% and 72%, respectively). These smart SMPIs and SMPCs exhibit flexible deformation properties that extend the potential use of polyimides and their composites to applications such as lightweight deformable sensors for the exploration industry.