Particulate 45S5 Bioglass with an average size of 46 microm was incorporated into a high density polyethylene (HDPE) for potential medical applications. Composites with Bioglass volumes of 10, 20, and 40% were produced by a manufacturing process consisting of blending, compounding, powdering, and compression molding. The Bioglass particles were well dispersed, and their homogeneous distribution in the polymer matrix, achieved after compounding, was retained during subsequent composite processing. The Young's modulus and microhardness of the composites increased with an increase in Bioglass volume while the tensile strength and fracture strain decreased. Fourier transform infrared spectra, obtained from Bioglass/HDPE samples exposed for 20 h at 37 degrees C to a simulated body fluid (SBF-9), demonstrated that composites of all the compositions examined developed the surface biological apatite layer equivalent to that for bulk Bioglass.