在非异酸聚氨酸中结构-玻璃过渡关系
Konstantinos N Raftopoulos1, Izabela Łukaszewska1, Sebastian Lalik2
1Department of Chemistry and Technology of Polymers, Cracow University of Technology, Warszawska 24, 31-155 Kraków, Poland.
Molecules (Basel, Switzerland)
|September 14, 2024
概括
这项研究研究了非异酸盐多酸氨 (PHU),发现基于聚乙烯的二环碳酸盐显著影响了玻璃过渡. 特性氨基还通过结构和键影响了这种过渡.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 非异酸盐聚氨酸 (PHU) 为传统聚氨酸提供了更安全的替代品.
- 了解分子动力学和玻璃过渡对于定制PHU特性至关重要.
- 特定的胺结构和聚碳酸盐特征对PHU行为的影响需要详细调查.
研究的目的:
- 研究由聚乙烯基二环碳酸盐 (P-CCs) 和各种二胺合成的PHUs的分子动力学和玻璃过渡.
- 阐明特征性氨基结构,摩尔比率和P-CC特性对材料热和动态行为的影响.
- 在这些PHU系统中,将分子移动性与电荷传输特性相关联.
主要方法:
- 均等多元加法反应合成PHUs.
- 红外光谱 (IR) 用于化学结构分析.
- 微分扫描热量计 (DSC) 用于热量计玻璃过渡.
- 宽带介电光谱 (BDS) 用于动态玻璃过渡 (α放松) 和分子放松 (β放松).
主要成果:
- 基于聚乙烯的二环碳酸盐 (P-CC) 被确定为玻璃过渡温度的主要决定因素.
- 由于其体积庞大的结构,自由体积引入和结合,特有的胺影响了玻璃过渡.
- 电荷移动性与分子移动性直接相关,由直流电导率和α放松频率之间的比例表示.
- 碳基单元波动 (β放松) 对局部环境变化表现出较小的敏感性.
结论:
- 通过修改P-CC组件,可以显著调整PHU特性,特别是玻璃过渡.
- 特征性氨基在调节玻璃过渡和材料特性方面起到次要但重要的作用.
- 电荷和分子移动性之间的强合表明设计导电PHU材料的潜力.
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