Federal University of Sao Carlos, Graduate Program in Materials Science and Engineering, Rodovia Washington Luiz, Km 235 SP-310, 13565-905 São Carlos, SP, Brazil.
Federal University of Sao Carlos, Graduate Program in Materials Science and Engineering, Rodovia Washington Luiz, Km 235 SP-310, 13565-905 São Carlos, SP, Brazil; Federal University of Paraiba, Department of Chemical Engineering, 58059-900 João Pessoa, PB, Brazil.
Carbohydr Polym. 2023 Jul 1;311:120733. doi: 10.1016/j.carbpol.2023.120733. Epub 2023 Feb 23.
Cross-linking has been used as a strategy to improve the mechanical properties of starch films. However, the concentration of the cross-linking agent and the cure time and temperature determine the structure and properties of the modified starch. This article, for the first time, reports the chemorheological study of cross-linked starch films with citric acid (CA) through monitoring the storage modulus as a function of time G'(t). In this study, a CA concentration of 10 phr showed a pronounced increase of G'(t) during the cross-linking of starch, followed by a constant plateau. Analyses of infrared spectroscopy validated the result chemorheological. In addition, the mechanical properties showed a plasticizing effect of the CA at high concentrations. This research demonstrated that chemorheology is a valuable tool in the study of starch cross-linking, which becomes a promising technique to evaluate the cross-linking of other polysaccharides and cross-linking agents.
交联已被用作提高淀粉薄膜机械性能的策略。然而，交联剂的浓度、固化时间和温度决定了改性淀粉的结构和性能。本文首次报道了通过监测储能模量随时间的变化来研究柠檬酸（CA）交联淀粉薄膜的化学流变学。在这项研究中，CA 浓度为 10 phr 时，淀粉交联过程中 G'（t）明显增加，随后趋于恒定平台。红外光谱分析验证了化学流变学的结果。此外，机械性能显示 CA 在高浓度下具有增塑作用。这项研究表明，化学流变学是研究淀粉交联的一种有价值的工具，它成为评估其他多糖和交联剂交联的有前途的技术。
