聚乙烯醇薄膜改性及应用进展

Progress in Modification and Application of Polyvinyl Alcohol Film

由于聚乙烯醇(PVA)具有可生物降解的特性,使其受到了全世界的关注,但PVA分子中含有大量的羟基基团,熔融温度和分解温度十分接近,导致其难以热塑加工,在一定程度上限制了其应用和推广。文章综述了PVA热塑加工改性的方法,来克服对PVA结构、加工上存在的限制。主要介绍了增塑改性和共混改性2种改性方法,其中,增塑改性着重介绍了普通、复配及新型增塑剂增塑改性PVA,使其熔点、结晶温度降低,热稳定性提高等,而共混改性主要介绍了PVA与淀粉、壳聚糖(CS)、纤维素(CE)3种天然可降解高分子的共混以及与聚乳酸(PLA)、聚己内酯(PCL)、聚羟基烷酸酯(PHA_(X))3种合成可降解高分子的共混,并介绍了改性PVA的相容性、力学性能、生物降解性等性能。在此基础上,文章还重点综述了改性PVA作为薄膜材料的应用。

The environmental protection characteristics of biodegradable polyvinyl alcohol(PVA)have been widely recognized all over the world.However,PVA molecules contain a large number of hydroxyl groups,its melting temperature and decomposition temperature are very close,which makes it difficult to thermoplastic processing,which limits its promotion and application to a certain extent.In view of this problem,the processing modification methods of PVA were reviewed to overcome the limitations on the structure,processing and unique properties of PVA.Two kinds of modification methods were introduced:one is plasticizing modification,which focuses on the common,compound and new plasticizers to plasticize PVA,so as to reduce its melting point,crystallization temperature and improve its thermal stability;another one is blending modification,which mainly introduces the blending of PVA with three natural degradable polymers of starch,chitosan(CS)and cellulose(CE),and the blending of PVA with three synthetic degradable polymers of polylactic aci(PLA),polycaprolactone(PCL)and polyhydroxyalkanoate(PHA_(X)).The compatibility,mechanical properties and biodegradability of the modified PVA were emphasized.In addition,the application of modified PVA as film material was introduced.