Improving the compatibility of polycarbonate/UHMWPE blends through gamma-ray irradiation

Gamma-ray irradiation treatment in air has been used as an alternative to the common surface treatment of ultrahigh molecular weight polyethylene (UHMWPE) powders to induce some oxygen-containing groups onto the molecular chain of UHMWPE to enhance its compatibility with polycarbonate (PC). The effect of gamma-ray irradiation on the structure and properties of UHMWPE was studied by FTIR, gel content measurement, mechanical property testing, and melt flow rate measurement. The mechanical properties and compatibility of polycarbonate/gamma-ray irradiated UHMWPE (gamma-UHMWPE) blend were also studied. The experimental results show that gamma-ray irradiation partly causes oxidative degradation of UHMWPE and the content of oxygen-containing groups increases with irradiation dose. The surface hydrophilicity of UHMWPE is improved due to the presence of oxygen-containing groups. SEM observation of the fractured surface of the PC/UHMWPE blends indicates the compatibility is improved through gamma-ray irradiation. Meanwhile, improved fracture toughness and mechanical strength can also be achieved; both yield and notched impact strength of PC/gamma-UHMWPE blends are greatly increased from 39.7 MPa and 9.9 kJ/m(2) to 49.2 MPa and 24.9 kJ/m(2), respectively, compared with the PC/UHMWPE (85/15) blend. Gamma-ray irradiation treatment is efficient for enhancing the compatibility of polycarbonate/UHMWPE blends.