纳米SiO_(2)对淀粉/壳聚糖膜性能的影响

Nano-SiO_(2) Effect on Performance of Starch/Chitosan Edible Film

为了提高可食性膜的应用价值,将淀粉(料液比3%)充分搅拌糊化后,加入壳聚糖/丙酸钙混合液、甘油增塑剂及纳米SiO_(2)(0.5%~3.5%悬浮液),50℃恒温水浴下搅拌30 min,采用流延法制得可食性膜。主要研究了表面处理前后纳米SiO_(2)对膜力学性能、透水量和热降解性能的影响。结果表明,当表面处理后纳米SiO_(2)含量为2.5%时,复合膜拉伸强度可以达到26.87 MPa,与未添加时相比,拉伸强度提高了43.92%,断裂伸长率可达36.65%,降低了0.56%;最低水蒸气透过量为154 g/(m^(2)·d),降低了26 g/(m^(2)·d);相同温度下,纳米SiO_(2)改性后的样品热降解残留量明显增多。

In order to confer good application value on edible film,after mixing starch with distilled water(3%material-liquid ratio),added into the chitosan/calcium propionate mixed liquid and plasticizer,nano-SiO_(2)(0.5%~3.5%)suspension was added then.The mixture was stirred in a water bath at 50℃for 30 min,the edible packaging film was prepared by casting method.The mechanical properties,water permeability and thermal degradation performance of the film were investigated respectively.The results showed that the tensile strength were 26.87 MPa when the composite film modified by 2.5%nano-SiO_(2),the tensile strength increased by 43.92%.Compared with not joined nano-SiO_(2),the elongation at break was 36.65%,decreased by 0.56%,and the lowest water permeability was 154 g/(m^(2)·d),decreased by 26 g/(m^(2)·d),the thermal degradation residue increased significantly at the same temperature.