Of .pvp / Pva Gel Cartilage Repair Material Preparation And Performance

Hydrogel composite is a promising articular cartilage repairing material. In this dissertation, PVP/PVA gel composite was prepared with freezing/thawing method. The micro-morphology an and structure were characterized by many experimental techniques such as SEM, FTIR. The hydrophilicity, mechanical and biotribological properties of PVP/PVA composite were studied. The main contents and results are as follows:1. PVP/PVA gel composite has good hydrophilicity. With the content of PVP increasing, hydrophilic properties of gel composite improved, along with the rise of water content and the fall of contact angle. For example, compared with pure PVA hydrogel, water content of PVP/PVA composite with the PVA content of 15% increases from 72.8% to 82.3% after adding 4wt% PVP, while the contact angle decreases from 36.3°to 26°. With the increasing of PVA content and freezing/thawing cycle times, water content decrease.2. The change behaviors of tensile and compressive stress of the gel composite with the strain are accorded with non-linear characteristics. Both tensile strength and compressive strength of the composite increase with the rise of freezing/thawing cycle times. The tensile and compressive strength firstly increase and then tend to reducing with the increasing of PVP content. While PVA content is 15% and PVP content is 1%, the tensile and compressive strength attain their maximum values. The tensile modulus and compressive modulus of the composite increase with the rise of strain.3. The friction coefficient of the gel composites increases with the rise of load and decreases with rise of radium of stainless steel ball and sliding speed. The friction coefficient decreases firstly and then increases with the rise of PVP content. The minimum value is 0.028 while PVP content is 1%. The friction coefficient of the gel composites is lower under bovine serum lubrication than that under distilled water and physiological saline lubrication.4. For the PVP/PVA gel composites used as an articular cartilage, the optimum preparation process of PVP/PVA gel composites is15wt% PVA and 4wt% PVP by 5 freezing/thawing cycle times.