可用于人工关节润滑的水凝胶蠕变缓释性能及理论模型

Aiming at the problems of difficult quantitative supply of the lubricant in artificial joint, resulting in serious wear of prosthesis surface a method for supplying and preserving joint lubricant by using hydrogel to simulate the structure of articular capsule is proposed, experimental exploration and theoretical verification are carried out. Firstly, the hyaluronic acid agar hydrogel is prepared, and the unconfined compression creep release test is carried out in the saline immersion environment. The relationship curves between creep volume, medium release and pressure are obtained, and the conversion formula between creep volume and medium release is obtained. Then, based on the structure and properties of hydrogels, a constitutive model of coupled diffusion and large deformation theory is established, under the given pressure condition, the creep curve of hydrogel can be obtained through the model. Finally, the release rate of gel medium can be deduced from the transformation formula obtained from the experiment. A finite element inverse method technology combining the test results with the finite element modeling and optimization method is used to obtain the material parameters of the experimental sample, which are used to simulate the creep behavior under different pressures, the results show that the creep release volume of hyaluronic acid agar hydrogel under constant pressure is proportional to the creep volume. Under the given pressure and action time, the coupled diffusion and large deformation theoretical models can quantitatively predict the release quantity of hyaluronic acid agar hydrogel within the permissible range of error. The research results can provide references for future hydrogel as artificial joint capsule for quantitative lubrication of artificial joints.