The Preparation And Property Of Starch/PVA Membrane For Guiding Tissue Regeneration

Starch is natural polymer with good biocompatibility and biodegradability, but poor mechanical properties. PVA is synthetic polymer with good mechanical properties but poor biodegradability. Starch/PVA membrane which combined the advantages of natural polymer and synthetic polymer was prepared in this study. Starch and PVA composites are studied in many fields, but starch/PVA membrane was studied in guiding tissue regeneration for the first time. The porous starch/PVA membrane was prepared by freeze-drying, the membrane's precessing conditions were investigated. And its surface topography, fracture surface morphology, mechanical properties, porosity and water absorption, biocompatibility and degradation were characterized in this study. The following conclusions:Starch/PVA membrane with different porous structure was prepared directly by freeze-drying. The surface morphology was investigated through adjusting the concentration, pre-freezing temperature, the mass ratio of starch and PVA. The thickness of the starch/PVA membrane is difficult to control and the thickness was unevenly distributed.The preparing process of starch/PVA membrane was improved, through solution casting and drying in room temperature, soaking in water, freeze-drying. Its thickness could be controlled and the relatively uniform thickness was controlled in 0.05-0. 1mm. The properties of starch/PVA membrane were studied through adjusting concentration, pre-freezing temperature, the mass ratio of starch and PVA. The conclusion is following: the pore size of starch/PVA membrane surface was 1-50μm, and internal interconnected pore structure was formed, mechanical strength was 12-26MPa, porosity was 60%-70%, water absorption was above 250%, no cytotoxicity, L929 cells and MC3T3 cells could adhere on the material surface, and the mass loss after a month was 14%-28%.Starch/PVA/HA membrane was prepared by adding HA in the starch and PVA mixture. HA has good biocompatibility and biological activity. The surface topography and fracture surface morphology, mechanical properties, biocompatibility were characterized. The conclusion is following:the pore size in the starch/PVA/HA membrane surface is less than 1μm, internal interconnected pore structure was formed, starch/PVA/HA membrane has better mechanical properties than starch/PVA membrane in drying state, their mechanical properties is similar in wet state, starch/PVA/HA membrane has good biocompatibility.