Preparation and property of high strength and low friction PVA-HA/PAA composite hydrogel using annealing treatment

PVA hydrogels have desirable characteristics for use as soft tissue substitutes. However, PVA hydrogels are not high strength enough to withstand the demanding in load-bearing environment of human. In this paper, a high strength and low friction PVA-HA/PAA composite hydrogel is obtained by freezing-thawing and annealing method. The microstructure, thermal stability, mechanical and biotribological properties of the hydrogel are studied. Annealing PVA-HA/PAA composite hydrogel has porous structure, interaction occurred between PVA, HA and PAA. HA particles are distributed in PVA matrix and played a role of diffuse strengthening and toughening. Annealing improves the crystallinity and crosslinking of the hydrogel, annealing PVA-HA/PAA composite hydrogel has good thermal stability, strength and mechanical properties. The tensile strength of annealing PVA-HA/PAA composite hydrogel can be up to 3.71 MPa. Annealing PVA-HA/PAA composite hydrogel has favorable lubricating properties, and the friction coefficient is very low.