在不同的甘油水系统下,研究各种粉分子的链段运动
Liping Mei1, Zhijie Zhu1, Caihong Wang1
1Anhui Engineering Laboratory for Agro-Products Processing, School of Tea & Food Science and Technology, Anhui Agricultural University, Hefei 230036, Anhui, China.
International journal of biological macromolecules
|January 10, 2024
概括
电子偏磁共振 (EPR) 光谱显示了粉分子运动在糖-水系统. 甘油度影响粉链的动态,粘度较高的减速运动,而性玉米粉显示出增加的移动性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 生物物理学的生物物理.
背景情况:
- 粉的分子动力学对其应用至关重要.
- 了解基于粉的材料在不同溶剂中的行为至关重要.
- 糖是一种常见的塑化剂,影响了聚合物特性.
研究的目的:
- 为了研究糖醇和水混合物中粉的分子运动.
- 为了阐明糖醇度对粉链动态的影响.
- 为了比较不同类型的粉的行为 (玉米粉,状玉米粉,高粉玉米粉).
主要方法:
- 用4-氨基-TEMPO对粉基组进行旋转标记.
- 电子磁共振 (EPR) 光谱检测分子运动.
- 福利埃变换红外 (FTIR) 和1H核磁共振 (1H NMR) 光谱用于确认.
- 标签后结晶性变化的分析.
主要成果:
- 在所有类型中,Spin标签显著降低了粉晶度.
- 在粉-甘油-水系统中,EPR确定了快速和缓慢的分子运动组件.
- 在20%的甘油中,减速运动消失了,表明链段旋转速度更快.
- 增加的甘油 (50-80%) 导致由于较高的粘度导致运动减慢.
- 状玉米粉由于其分支结构而表现出增强的链流动性.
结论:
- 甘油度动态影响粉分子运动.
- 这项研究提供了对粉-水-甘油系统动态的直接见解.
- 玉米粉的独特结构影响其与糖醇和水的相互作用.
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