Electro-induced tensile deformation of over-braiding composite tube with carbon fiber reinforced shape memory polyurethane filament

2D shape memory composite tubes, which has excellent flexibility and high durability, have been widely used in intelligent material design. Here we report fabrication of an over-braiding pure shape memory polyurethane (SMPU) and continuous carbon fiber reinforced SMPU (CCF/SMPU) braided tubes with different braided layers (L1, L2, L3). The dynamic thermomechanical behaviors, tensile properties, shape memory behaviors and tensile recovery forces had been investigated. Tensile shape recovery force was recorded to find effects of recovery temperature, applied voltage on the shape memory behaviors. We found that the tensile load, shape recovery ratio and recovery force increase with the braided layers increased. The maximum shape recovery ratio could be reached to 98.8% and shape recovery force of over-braiding CCF/SMPU composite tube was up to 14.825 N. The infilling of carbon fibers could improve the tensile strength and shape memory behaviors simultaneously. Such an effect could be benefit to explore applications of braided composite structures both with high strength and deformation recovery capacity.