淀粉/壳聚糖复合膜的制备、性能及抗菌改性研究

Study on Fabrication,Performance and Antibacterial Modification of Starch/Chitosan Composite Films

以淀粉为原料,采用壳聚糖(CTS)和经十二烷基苯磺酸钠(SDS)表面改性的纳米二氧化钛(M-Nano-TiO_(2))为填充相,以共混法制备了不同比例的淀粉/壳聚糖复合膜(淀粉/CTS)及M Nano-TiO_(2)填充的淀粉/壳聚糖三组分复合膜(淀粉/CTS/M-Nano-TiO_(2)).利用红外光谱(FTIR)、扫描电子显微镜(SEM)、X射线衍射仪(XRD)对复合膜的微观结构及性能进行表征分析,测试薄膜的力学性能和透光性能.结果表明:淀粉糊化液和壳聚糖溶液体积比为4∶3,纯固体分质量比为1∶1时薄膜抗拉强度最高,为28.62 MPa,断裂伸长率达3.2%,透光率随CTS含量的增加而提高,两类复合膜各组分均相容良好,结晶性能相较单一淀粉膜有所下降,微观表面平整光滑.加入了M-Nano-TiO_(2)的复合膜有较好的抗菌性能,对大肠杆菌和金色葡萄球菌的抑菌率分别提高了7.9%和5.9%.

Starch is used as raw material.Chitosan(CTS)and titanium dioxide(M-Nano-TiO_(2))nano particle modified by sodium dodecylbenzene sulfonate(SDS)are served as filling phases.Starch/chitosan blend com-posite films(starch/CTS)with different proportions and starch/chitosan three-component composite films(starch/CTS/M-Nano-TiO_(2))filled with M-Nano-TiO_(2)are prepared by a blending method.The microstructure and properties of the composite films are characterized and analyzed by using infrared spectroscopy(FTIR),scanning electron microscopy(SEM),and X-ray diffraction(XRD).The mechanical properties and light transmittance of the films are also tested.The results show that when the volume ratio of starch gelatinizing solution and chitosan solution is 4∶3,and the mass ratio of pure solids is 1∶1,the tensile strength of the film is the highest to 28.62 MPa.and the elongation at break is 3.2%.The light transmittance is enhanced with the increase of CTS content.The components of the two types of composite films are well compatible,and the crystallinity is decreased as comparison to that of the single starch film.The micro surface is smooth.The composite film added with M-Nano-TiO_(2)has good antibacterial properties,the antibacterial rates against Escherichia coli and Staphylococcus aureus are increased by 7.9%and 5.9%,respectively.