[Crosslinking modification of ultra high molecular weight polyethylene during joint arthroplasty]
Gang Tong1, Hua Tian2, Caimei Wang
1Department of Orthopedics, Peking University Third Hospital, Beijing 100191, China.
Objective:
To explore the optimal condition of crosslinking modification of ultra high molecular weight polyethylene (UHMWPE) by gamma ray irradiation.
Methods:
The hip and knee joint samples of UHMWPE were tested with regards to friction and wear performance at different doses of (60)Co radiation and heat treatment. And the optimal condition of crosslinking was determined by wear performance and physicochemical properties.
Results:
Under the condition of 75 kGy irradiation and 150 °C heat treatment, crosslinked UHMWPE showed the best performance. Acetabular sample wear rate decreased 63.24% and knee sample wear rate decreased 59.95% compared with conventional UHMWPE. The modified material had excellent mechanical properties of impact strength 83 kJ/m², tensile strength 50.32 MPa, yield strength 21.83 MPa and elongation at break 312%. Also the material showed excellent antifatigue and reliable chemical properties.
Conclusion:
The optimal condition of crosslinking modification of UHMWPE is 75 kGy irradiation after 150 °C heat treatment.
