Morphologies and Structures of Waxy Corn Starch Dispersed in a 1-Allyl-3-Methylimidazolium Chloride/Water Binary Blend System
Article
Figures
Metrics
Preview PDF
Reference
Related
Cited by
Materials
Abstract:
In this study, the effect of the ionic liquid 1-allyl-3-methylimidazolium chloride (AMIMCl) and a AMIMCI/water binary blend system on the morphologies, thermal properties, crystalline structures, and related properties of waxy corn starch granules were systematically studied. A hot-stage microscope was used to monitor the morphological changes of starch granules in the ionic liquid/water binary blend system at room temperature and during the heating process. The thermal behavior and crystallinity of the ionic liquid-treated starch sample were characterized by differential scanning calorimetry (DSC) and X-ray diffraction. The results showed that the AMIMCl/water blend system had a significant impact on the morphology and crystalline structure of starch granules; these properties were closely related to the AMIMCI content. When the AMIMCl content in the solution was less than 50%, the temperature range for the disappearance of the cross-polarization of starch increased with increasing AMIMCI content, consistent with the observation that the endothermic peak in DSC was shifted to the high-temperature side. When the gelatinization temperature was increased to 84 ℃, the strengths of the intramolecular and intermolecular forces of starch increased. When the AMIMCl content in solution was more than 50%, the gelatinization temperature and enthalpy decreased to 62 ℃ and 12.45 J/g, respectively. At the same time, the interchain structures of starch were destroyed, the stability of starch molecules decreased, and starch dissolution and gelatinization occurred simultaneously. In pure AMIMCl, because of the absence of water, only starch dissolution occurred and became more apparent with increasing storage time.