Determination of Shape Fixity and Shape Recovery Rate of Carbon Nanotube-filled Shape Memory Polymer Nanocomposites

Shape memory polymers (SMP) feature the ability of the polymers to recover their original/permanent shape from deformed/temporary shape with the presence of stimulus such as heat, light, or vapor. Shape Memory Polyurethane (SMPU) reinforced with multi-walled carbon nanotubes (MWNTs) were fabricated with through mixing and injection molding with the purpose to improve the shape memory properties of the polymer at low filler content. Variables such as shape fixity and recovery have been measured to evaluate the effect of nanotube fillers on the shape memory behavior of the prepared composites. Thermomechanical test were performed and the shape fixity and shape recovery rate were analyzed. Additions of nanotube fillers increase the relative shape fixity of the polymer nanocomposites while the experimental results demonstrate that the presences of nanotube fillers reduce the shape recovery rate. The shape recovery of the polymer nanocomposites were decreased due to the limited movement of polymer chains by the MWNTs. (C) 2012 The Authors. Published by Elsevier Ltd. Selection and/or peer-review under responsibility of the Centre of Humanoid Robots and Bio-Sensor (HuRoBs), Faculty of Mechanical Engineering, Universiti Teknologi MARA.