Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Cerro Blanco No. 141, Col. Colinas del Cimatario, C.P. 76090 Santiago de Querétaro, QRO, Mexico; Centro de Desarrollo de Productos Bióticos del Instituto Politécnico Nacional, Km 8.5, Carretera Yautepec-Jojutla, Colonia San Isidro, Apartado Postal 24, 62731 Yautepec, MOR, Mexico.
Centro de Desarrollo de Productos Bióticos del Instituto Politécnico Nacional, Km 8.5, Carretera Yautepec-Jojutla, Colonia San Isidro, Apartado Postal 24, 62731 Yautepec, MOR, Mexico.
Carbohydr Polym. 2015;127:195-201. doi: 10.1016/j.carbpol.2015.03.074. Epub 2015 Mar 28.
This study considered the effect of amylose content (30% and 70%), montmorillonite (MMT) fraction (5 and 15%) and preparation method on mechanical and barrier properties of starch/clay nanocomposites prepared by casting. In Method 1, (30% w/w) glycerol was incorporated before starch gelatinization and MMT addition, while in Method 2 after gelatinization and MMT addition. Nanocomposites with higher amount of MMT showed the highest tensile strength and Young's modulus for both preparation methods. Method 1 favored nanocomposite properties of films with less amylose content, meanwhile Method 2 favored nanocomposites properties with higher amylose content. Water vapor permeability did not decrease significantly in starch films with different amylose content with the two different preparation methods. X-ray diffraction of the starch films indicated intercalated structures. Higher melting temperature (Tm) was found for nanocomposites with Method 2, indicating more ordered structures. Films with 70% amylose content have higher Tm than films with 30% amylose.
本研究考察了直链淀粉含量（30%和 70%）、蒙脱土（MMT）含量（5%和 15%）和制备方法对铸膜法制备的淀粉/粘土纳米复合材料的力学性能和阻隔性能的影响。在方法 1 中，在淀粉糊化和加入 MMT 之前加入（30%w/w）甘油，而在方法 2 中则在淀粉糊化和加入 MMT 之后加入。对于两种制备方法，含有较高 MMT 含量的纳米复合材料表现出最高的拉伸强度和杨氏模量。方法 1 有利于低直链淀粉含量薄膜的纳米复合材料性能，而方法 2 有利于高直链淀粉含量的纳米复合材料性能。用两种不同的制备方法，不同直链淀粉含量的淀粉膜的水蒸气透过率并没有显著降低。淀粉膜的 X 射线衍射表明存在插层结构。方法 2 制得的纳米复合材料的熔融温度（Tm）较高，表明其结构更有序。直链淀粉含量为 70%的薄膜的 Tm 高于直链淀粉含量为 30%的薄膜。
