Preparation And Properties Of PVA Based Gel With γ Irradiation As Repairing Material For Articular Cartilage

The injury of articular cartilage is a common form of the joint pain,and it's a common disease in clinical orthopedics.There is an impetus for the development of an ideal material for articular cartilage repairing for a long time.Polyvinyl alcohol(PVA) hydrogel is a hydrogel not only with normal gel performance,but with low toxicity and good mechanical properties,high water absorption and the advantages of good biocompatibility.It's a promising artificial cartilage repairing material.In order to improve the properties of PVA hydrogel as artificial cartilage repairing materials,the PVA/PVP gel composite was prepared combining the methods of freezing-thawing andγ-irradiation cross-linking.We prepared PVA/PAAM gel composite with freezing-thawing methods and investigated its the feasibility of it as artificial cartilage repairing materials.The micro-morphology and structure were characterized by many experimental techniques such as SEM and FTIR.The hydrophilicity,mechanical and biotribological properties of PVA/PVP gel composite were systemically studied.The hemolytic property of PVA/PVP gel composite was tested.The main contents and results are as follows:1.The PVA/PVP gel composite prepared by a combination of freezing-thawing andγ-irradiation methods had a porous structure similar to natural articular cartilage.Afterγ-irradiation,the toughness of PVA/PVP gel composite surface was improved and the internal network structure was strengthened,so the wear could be reduced.2.The hydrophilicity of PVA/PVP gel composite was studied.We also tested the hemolytic property of PVA/PVP gel composite as biomedical material.The result showed its good biocompatibility.3.The change behavior of tensile and compressive stress with the changes of strain shows a non-linear relationship.Both tensile strength and compressive strength of the composite increased firstly and then decreased with the rise of irradiation dose,increase with the rise of freezing-thawing cycle times.The tensile and compressive strength had the maximum value when the irradiation dose was 100kGy.The tensile and compressive modulus of the composite increased with the increase of strain.4.The biotribological properties of PVA/PVP gel composite under different conditions were studied.The factor such as irradiation dose,freezing-thawing cycle times,load,degree of PVA polymerization,addition of PVP and different wear counterparts all affected the gel's properties.Friction coefficient had some changes after irradiation.Friction coefficient was relatively small when irradiation dose was 100kGy.And friction coefficient was increased alone with the increase of freezing-thawing cycle times.The friction coefficient of the gel composites was lower in bovine serum than that in distilled water and physiological saline.5.The preparation,mechanical and biotribological properties of PVA/PAAM gel composite were studied,and the feasibility of this composite as articular cartilage repairing material was explored.6.PVA/PVP gel composite had the mechanical and biotribological properties similar to natural cartilage.It's a promising articular cartilage repairing material.