A tough PVA/HA/COL composite hydrogel with simple process and excellent mechanical properties

Designing a hydrogel that matches natural cartilage in composition, structure, and properties has been challenging. In this study, polyvinyl alcohol (PVA), hyaluronic acid (HA) and collagen (COL) were used as raw materials to prepare composite hydrogels by the freezing-thawing method. The microcosmic characterization was characterized by scanning electron microscopy (SEM), Fourier transforms infrared (FTIR) and X ray diffractometer (XRD), respectively. A three-dimensional network structure similar to that of natural articular cartilage was observed in the composite hydrogels. The mechanical properties were investigated by tensile test and sliding friction test, illustrating that the 15%PVA-0.05%HA-1%COL hydrogel displays excellent tensile strength and elongation, reaching up to 1.62 MPa and 532%, respectively. Furthermore, the friction properties of the composite hydrogels are significantly better than that of the pure PVA hydrogel, and the average friction coefficient is less than 0.13. Thus, it is believed that this work provides a tough PVA/HA/COL composite hydrogel with simple process and excellent mechanical properties for cartilage tissue engineering as candidate materials.