Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 03, 2023 - September 06, 2023
The purpose of this study is to elucidate the boundary lubrication mechanism of the cooperation of hyaluronic acid (HA) and phospholipids (DPPC) between articular cartilages. As the cartilage tissue model, polyvinyl alcohol (PVA) hydrogel, which has similar water content and elasticity. PVA hydrogel was prepared as follows; PVA powder was solved into deionized water completely, then set in an environmental tester for repeat freezing and thawing to grow physical crosslinks. A rotational rheometer was used for the friction test since this apparatus could realize the evaluation in wide sliding velocity, between 10-5 to 103 mm/s. As a result, characteristic frictional behavior was observed, friction coefficient increased in the boundary lubrication range with sliding velocity. Comparing PBS, adding HA and DPPC changed the friction behavior. Especially, 0.02wt% of DPPC solution indicated a significant friction reduction, with or without HA. And in the case of 0.01wt% of DPPC, friction decreased with HA concentration. These results implied that the roles of HA and DPPC for the friction were different and the appropriate ratio of them would exist to minimize friction.
