在DGEBA-EDA系统中对粘性弹性的非静态度影响:从Brillouin光散射的洞察力
1Faculty of Physics and Astronomy, Adam Mickiewicz University, Poznań 61-614, Poland.
The journal of physical chemistry. B
|October 25, 2024
概括
使用Brillouin光谱学研究双甲和乙基二的固化反应,揭示了对粘弹性质的关键见解,并确定了特定成分的玻璃化点,而不是凝点.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 环氧树脂与氨基的固化反应对材料性能至关重要.
- 了解从初始到最终阶段的过渡对于预测材料性能至关重要.
- 粘弹性特性显著影响交联聚合物的机械行为.
研究的目的:
- 研究双甲基 (DGEBA) 和乙烯基胺 (EDA) 的二甲基乙烯基乙烯 (DGEBA) 之间的异热固化反应的初始和最终阶段.
- 测量高频声学参数并分析它们的度依赖性.
- 解释与粘弹性特性相关的机械参数的观察到的变化,并确定关键组成.
主要方法:
- 采用Brillouin光散射光谱法来测量高频声学参数.
- 测量是在一系列的二胺摩尔分数中进行的,从纯预聚合物到纯交叉链接剂.
- 在初始和最终固化阶段分析了机械参数的度依赖性.
主要成果:
- 在初始和最终固化阶段之间观察到机械参数度依赖性的显著差异.
- 两个特征性的非静态度组合 (氨基过量和环氧过量) 在最后阶段显示出度依赖的显著变化.
- 实验数据表明,这些特征性成分代表了玻璃化点,而不是弗洛里的临界凝点.
结论:
- 这项研究强调了环氧胺固化不同阶段的明显粘弹性行为.
- 在最终固化阶段的特征成分被确定为玻璃化点,这对于理解材料特性至关重要.
- 这一发现挑战了这些点作为聚合物网络形成中的关键凝点的传统解释.
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