具有可变相互作用强度的模型复杂同膜的玻璃动态由临界盐度量化
Nehil Shreyash1, Maninderjeet Singh1, Karan Kumar Paswan2
1William A. Brookshire, Department of Chemical & Biomolecular Engineering, University of Houston, TX 77204, USA. akarim3@central.uh.edu.
Soft matter
|November 26, 2025
概括
复杂的协体表现出改变的玻璃状动力学与变化的聚合物电荷密度. 增加相互作用强度提高了玻璃过渡温度,但降低了脆弱性,水分作为可塑剂.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物物理 聚合物物理
- 物理化学 物理化学
背景情况:
- 复杂的协体被用于各种行业,包括制造业,食品,个人护理和治疗.
- 虽然相位行为得到了很好的研究,但复杂的同类动物的玻璃状动态在很大程度上仍未被探索.
- 通用理论 (GET) 和模拟表明,聚合物电荷密度影响玻璃过渡温度 (Tg) 和脆弱性 (m).
研究的目的:
- 为了研究聚合物电荷密度对复杂协生物的玻璃动态的影响.
- 确定分子相互作用强度如何影响玻璃过渡温度 (Tg) 和脆弱性 (m).
- 探索湿度对这些材料玻璃状动态的影响.
主要方法:
- 介电光谱检测是在由聚二二二甲基氨基化物 (PDDA) 和三酸氨酸 (ATP) 组成的模型复杂的协膜上进行的.
- 用临界盐度 (csalt) 来衡量分子相互作用强度 (ε).
- 膜被真空回火并测量在一个广泛的温度范围内,接近Tg.
主要成果:
- 发现增加分子相互作用强度 (ε) 会增加玻璃过渡温度 (Tg),同时逐渐降低脆弱性 (m).
- 复杂的凝聚膜在室温 (1 kHz) 时表现出高的表面介电电容率 (> 10 ^ 3).
- 观察到水分可塑化玻璃般的动态,减少Tg.
结论:
- 聚合物电荷密度显著影响复杂协体的玻璃状动态,影响Tg和m.
- 高介电性解释了材料对电场的响应.
- 这些发现可以将其推广到各种应用中的复杂协体,并提供对其物质性质的见解.
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