论文标题
粒状复合材料的两个天然多糖的自分散
Self-dispersion of Two Natural Polysaccharides for Granular Composites
论文作者
论文摘要
我们设想,在介质上的两种聚合物材料之间的分散会产生新的复合材料,其特性比单独的组件要优越得多。在这里,我们阐明了两种最丰富的天然多糖,淀粉和壳聚糖之间的色散,它们形成了可能有助于许多应用的中尺度复合材料。通过使用X射线显微镜成像,小角度X射线散射以及差扫描量热法,我们能够表征壳聚糖和淀粉在中尺度复合材料中的相互作用。从淀粉颗粒的简单混合物中,该复合材料的形态要复杂得多,其大小为几微米和数百微米的壳聚糖微管。这种独特的形态只能通过淀粉颗粒基质中壳聚糖的可混杂性来解释。可以证明,壳聚糖中的氨基组与淀粉颗粒中的羟基之间存在离子相互作用。尽管壳聚糖在水中的溶解度有限,但这种离子相互作用允许在淀粉悬浮液中拆卸壳聚糖微管。结果是由两个生物相容性和可生物降解的多糖聚合物形成的化学更强,更稳定的颗粒复合材料。壳聚糖分散在淀粉颗粒中的机制对壳聚糖在水和其他溶剂中的应用有影响。
We envision that dispersion between two polymeric materials on mesoscales would create new composites with properties that are much more superior to the components alone. Here we elucidate the dispersion between two of most abundant natural polysaccharides, starch and chitosan, which form mesoscale composites that may promise many applications. By using X-ray microscopic imaging, small-angle X-ray scattering, and differential scanning calorimetry, we were able to characterize the interactions of chitosan and starch in the mesoscale composites. The morphology of the composite is far more complex from the simple mixture of starch granules with a nominal size of a few micrometers and chitosan microbundles of tens and hundreds of micrometers. This unique morphology can only be explained by the enhanced miscibility of chitosan in a starch granular matrix. It is evidenced that there is a possible ionic interaction between the amino group in chitosan and the hydroxyl groups in starch granules. Despite the limited solubility of chitosan in water, this ionic interaction allows for the disassembly of chitosan microbundles within the starch suspension. The result is a chemically stronger and more stable granular composite formed by two biocompatible and biodegradable polysaccharide polymers. The mechanism of chitosan to disperse throughout starch granules has implications for the application of chitosan in water and other solvents.