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Abstract
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This study aimed to obtain a compound with superior shape memory properties and a transfer temperature close to human body temperature. Therefore, by precise adjusting the combination of polypropylene carbonate (PPC), polycaprolactone (PCL) and graphene nanoplatelets (GNPs), an attempt was made to reach a transfer temperature of 37 0C.To improve the dispersion and performance of graphene nanoplatelets, its chemical modification with polyethylene glycol (PEG) was considered. X-ray energy diffraction spectroscopy analysis (EDX), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) was used to confirm the surface modification of nanoparticles. PCL/PPC blends and their nanocomposites were prepared via solution casting with different ratios (PCL/PPC: 10/90, 15/85, 20/80 w/w) in the presence of 0.5, 1, 1.5 phr of modified GNPs. Various techniques such as differential scanning calorimetry (DSC), scanning electron microscope (SEM), and dynamic mechanical thermal analysis (DMTA) were used to characterize samples. A traction device equipped with a temperature-controlled chamber was used to induce shape memory. The shape memory behavior of these blends was discovered to be highly dependent on their components. Samples containing 10 wt% PCL with 0.5 to 1 phr of modified GNPs achieved an optimal shape fixing ratio ( Rf) and recovery ratio ( Rr) with a memory transfer temperature close to human body temperature.
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