The effect of ultra-high molecular weight polyethylene fiber on the mechanical properties of acrylic bone cement

Abstract

The effects of the addition of ultra-high molecular weight polyethylene fiber (UHMWPE) on the mechanical properties of standard surgical Simplex-P radiopaque bone cement have been investigated. It was found that the tensile strength and tensile modulus were apparently not improved by the incorporation of UHMWPE in the acrylic bone cement. The results of bending strength and bending modulus indicated that a reinforcing effect is obtained at UHMWPE contents as low as 1 wt%, and then levelled off with increasing UHMWPE contents. When the UHMWPE contents as low as 2 wt%, the values of compressive strength and modulus seemed approximate the same; whereas the values of compressive strength and modulus decreased with increasing UHMWPE contents. From the results of dynamic mechanical analysis (DMA), the values of dynamic storage modulus of bone cement increased at UHMWPE fiber as low as 2 wt%, but beyond that UHMWPE content the value of the dynamic storage modulus decreased with increasing UHMWPE contents. The same results were also found for the dynamic loss modulus. When methyl methacrylate was grafted onto UHMWPE by plasma and UV irradiation treatment, it was found that by adding the treated UHMWPE fiber in acrylic bone cement had a significant reinforcing effect on the mechanical properties of bone cement.