Characterization of UHWPE-TiO₂ Composites Produced by Gelation/Crystallization Method

Abstract

In this study, ultra-high molecular weight polyethylene (UHMWPE) - TiO2 composites reinforced with TiO2 particles with weight ratios of 0.5, 1 and 2% were produced by gelation/crystallization method in decalin+antioxidant solution of UHMWPE at 150 degrees C, for 40 min by using magnetic stirrer. The gel mixture was cooled in an aluminum tray embedded in iced water under ambient conditions and dried in an oven at 130 degrees C for 90 min to remove any residual trace of decalin. Distribution and elemental analyses of TiO2 particles in polymer matrix was examined by SEM-EDS. Crystallization behavior was investigated by differential scanning calorimetry (DSC). Based on the results, TiO2 particles in the UHMWPE have accelerated the crystallization, acting as nucleating agents, with increment from 56% for UHMWPE to 63.5% for UHMWPE-2 wt% TiO2. The present bond types in composites were analyzed by Raman spectroscopy and the results are in good agreement with literature. Uniaxial tensile tests were performed to determine Young's modulus of UHMWPE-TiO2 composites. It was found that Young's modulus of UHMWPE was increased from 52 MPa to 800 MPa with the addition of TiO2 particles.