The objective was to find and characterise alternative grades of polyethylene in articulating surfaces of joint endoprostheses. Plates made of UHMW-PE (ultra high molecular weight polyethylene), strict linear Phillips-polyethylene and blends of both materials were sintered and subsequently crosslinked via electron beam irradiation (10 MeV, 50-150 kGy) in nitrogen atmosphere. Half of the specimens were annealed at 150°C in nitrogen for 2.5 hours. The level of crystallinity was determined with Differential-Scanning-Calorimetry. The solubility was measured in TCB with 0.03% BHT with cubical samples at a temperature of 160°C. The ratio of swelling and the crosslinking density were determined in p-xylene at 130°C with a swelling device. The molar mass and molar mass distribution was quantified by Size-Exclusion-Chromatography, at a temperature of 135°C and TCB as a solvent. The crystallinity of Phillips-PE was higher than that of UHMW-PE; no significant change concerning crystallinity could be observed due to irradiation; annealing over the melting point led to a decrease in crystallinity. The solubility after low dosages decreased significantly when UHMW-PE was added. This also led to a remarkable increase of the cross-link density. Higher irradiation rates led to lower solubilities; a complete cross-linking wasn't possible neither for the blends nor the neat PE. The SEC-measurement showed, that the addition was homogenous and the high molecular fraction was still detectable.