Wear Properties and Mechanical Properties of Slightly Cross-linked Ultra-high Molecular Weight Polyethylene crystallized under Uniaxial Compression
Makoto OHTA, Suong-Hyu HYON, Yu-Bong KANG, Masanori OKA, Sadami TSUTSUMI, Syozo MURAKAMI, and Shinzo KOHJIYA
Abstract:In order to improve the wear properties of artificial joints, a slightly cross-linked ultra high molecular weight polyethylene (UHMWPE) was compressed at molten state and crystallized by cooling to room temperature. The molecular chain of the UHMWPE was orientated to the direction of deformation. Density and melting point of the mold article were increased in accordance with compression ratio. The ac peak of loss modulus was shifted to higher temperature compared with the non-compressed sample. And it was also revealed that the weight loss of the compressed UHMWPE was remarkably less than that of a non-compressed sample from the result of the pin-on-disc wear test. Key Words:Slightly cross-link, Artificial joint, Wear resistance, Dynamic modulus, Compression ratio