中文摘要：

以六水合硝酸镁[Mg（NO3）2·6H2O]为增塑剂，采用流延法制备了增塑改性的淀粉-聚乙烯醇（PVA）复合膜，并研究了改性后淀粉-PVA复合膜的性能．研究结果表明，Mg（NO3）2·6H2O与淀粉和PVA发生一定的相互作用，破坏了淀粉和PVA中的结晶结构．因此，Mg（NO3）2·6H2O的加入可提高淀粉与PVA间的相容性，改变了淀粉-PVA复合膜的力学性能，使其拉伸强度下降，断裂伸长率提高．

英文摘要：

The plasticized starch/poly （vinyl alcohol） （PVA） film was prepared by casting method using magnesium nitrate hexahydrate [ Mg（ NO3 ）2· 6H2O] as the plasticizer. The micro morphologies of pure starch/ PVA and Mg （NO3 ）2 · 6H2O plasticized starch/PVA film were observed by scanning electron microscope （SEM）. The interaction between Mg（ NO3）2 · 6H2O and starch/PVA molecule was investigated by Fourier transform infrared （FTIR）. The crystallinity and thermal properties were measured by X-ray diffraction measurement（XRD） and thermogravimetric analysis （TGA）. The mechanical properties were measured by tensile testing and dynamic mechanical analysis（DMA）. It was found that Mg（NO3）2 · 6H2O could form some interaction with starch and PVA molecules. The addition of Mg（ NO3 ）2 · 6H2O could improve the miscibility of starch and PVA. The XRD results showed that Mg（ NO3 ）2 · 6H2O could destroy the crystals of starch and PVA. The TGA results showed that the thermal stability of starctCPVA decreased with the addition of Mg（ NO3 ）2 · 6H2O . Tensile testing showed that Mg（ NO3 ）· 6H2O was highly effective in modifying the mechanical properties of starch/PVA film, making the elongation at break of starch/PVA film largely increased from 8% of pure starch/PVA film to 514% with 60% Mg（NO3 ）2 · 6H2O .