本文以4种玉米淀粉（waxy、normal、G50、G80）制备淀粉-壳聚糖交联薄膜，利用扫描电子显微镜（SEM）、红外光谱分析仪（FTIR）、X-射线衍射仪（XRD）、接触角仪（CA）及热重分析仪（TGA）探讨了不同淀粉-壳聚糖交联薄膜的结构和性质差异。结果表明，壳聚糖自交联薄膜的断面易产生孔洞，而淀粉-壳聚糖交联薄膜断面中无孔洞结构；随着直链淀粉含量升高，交联薄膜断面的粗糙形貌更加明显。在交联体系中，壳聚糖与淀粉分子形成新的氢键，G50、G80自交联薄膜在2θ=17.36°附近弱衍射峰消失，4种淀粉-壳聚糖交联薄膜整体均呈无定型态；壳聚糖自交联薄膜的水接触角CA=76.57°±1.35°，不同链/支比淀粉与壳聚糖交联后，淀粉-壳聚糖交联薄膜的接触角均增大，且支链淀粉含量越高，薄膜的亲水性越强；同时，淀粉-壳聚糖交联薄膜的热稳定性低于壳聚糖或淀粉自交联薄膜。以上结果可为淀粉-壳聚糖交联薄膜在食品包装中的合理应用提供参考。

Starch-chitosan crosslinking films were prepared by starch with different amylose/amylopectin ratios (waxy, normal, G50 and G80). Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction technology (XRD), Contact angle meter (CA) and Thermal gravimetric analysis (TGA) were applied to characterize the morphology, multi-scale structures and thermal property discrepancies of starch-chitosan crosslinking films. The results showed that cavities were formed in the film prepared by the self-cross linkage of chitosan. When chitosan was crosslinked with starch, holes disappeared and homogenous fractured surface were newly formed in the film, and with the increase of amylose content, the roughness of cross-linked film was more obvious. In the meanwhile, new hydrogen-bonds were newly formed by crosslinking of chitosan and starch, the weak diffraction peaks around at 2θ=17.36° of G50 and G80 self-crosslinking films disappeared, and the interactions promoted amorphous structures formation in all chitosan-starch crosslinking films. The contact angle of chitosan self-crosslinking film was 76.57°±1.35°, when chitosan was crosslinked with starch with different amylose/amylopectin ratio, the contact angles of all starch-chitosan crosslinking films were increased, and films with higher amylopectin content showed stronger hydrophilia. The cross-linkage of chitosan and starch accelerated the depolymerization and decomposition of macromolecules, leading to lower thermal stabilities compared with the films by self-crosslinking of starch and chitosan. The results could provide reasonable utilization of starch-chitosan crosslinking film in the field of food packaging.

大学生创新创业训练计划(201811819039)，东莞理工学院高层次人才（创新团队）科研启动项目（KCYCXPT2017007）