中文摘要：

采用流延成膜法制备了以尿素／甲酰胺为复配增塑剂改性的聚乙烯醇（PVA）改性薄膜。采用FTIR研究了复配增塑剂尿素／甲酰胺和PVA之间的相互作用，采用XRD、DSC、TGA和拉伸性能测定对改性后的PVA膜性能进行了测试表征。结果表明，尿素／甲酰胺能与PVA形成氢键作用，破坏PVA的结晶结构，降低PVA膜的结晶度。尿素／甲酰胺的加入降低了PVA的熔点，提高了PVA的热分解温度。改性后的PVA膜的拉伸强度降低，断裂伸长率提高。

英文摘要：

The modified PVA films were prepared by casting method using urea/formamide as a mixed plasticizer. The interaction between urea/formamide and PVA was investigated by FTIR. The properties of urea/formamide plasticized PVA films were studied by XRD, DSC, TGA and tensile property testing. The results showed that the hydrogen bonding in PVA films was formed by the addition of urea/formamide. The crystalline of PVA was destroyed and the degree of erystallinity was reduced. The melting points of PVA films were reduced and the thermal decomposition temperature of PVA films was enhanced with the addition of urea/ formamide. PVA films lowered the tensile strength. The elongation at break was increased.