Shape memory and thermo-mechanical properties of shape memory polymer/carbon fiber composites

In this study, chopped carbon fiber reinforced trans-1, 4-polyisoprene (TPI) was developed via a proposed new manufacturing process with the aim of improving weak mechanical properties of bulk TPI bulk. Specimens of the developed shape memory polymer (SMP) composites were fabricated with carbon fiber weight fraction of 5%, 7%, 9%, 11% and 13%, respectively. Measured are the effects of chopped carbon fiber and temperature on: (a) shape recovery ratio and rate; (b) stress-strain relationship; (c) maximum tensile stress, strain and Young's modulus; and (d) maximum stress and residual strain under a constant strain cyclic loading. In addition, SEM micrographs were also presented to illustrate the fracture surface. The present experimental results show that the SMP with 7% carbon fiber weight fraction appears to perform best in all the tests. This indicates that the 7% carbon fiber weight fraction could be the optimum value for the SMP developed using the proposed manufacturing process.