环氧网的多尺度弹性通过风湿学和Brillouin光光谱学
Emmanouela Filippidi1,2, Anuj K Dhiman3, Benke Li2
1Department of Materials Science and Engineering, University of Crete, Heraklion 70013, Greece.
The journal of physical chemistry. B
|December 4, 2024
概括
光光谱学 (BLS) 测量GHz频率,与传统的风学不同. 环氧网络显示存储模块 (G) 在交叉连接时比纵向模块 (M) 增加更多,揭示了软材料弹性的洞察力.
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
- 频谱学是一种光谱学.
背景情况:
- 软材料表现出频率依赖的反应,通常在较低频率 (10−2102rad/s) 进行研究.
- 常规的方法,如学和原子力显微镜,往往是基于接触的或侵入性的.
- 了解低频粘弹性和高频弹性之间的关系至关重要,但仍然不清楚.
研究的目的:
- 通过使用互补技术,在不同频率的聚合物网络中比较机械模块.
- 为了研究剪切风湿学和布里卢恩光谱测量之间的相关性.
- 在不同的尺度上阐明软材料的弹性.
主要方法:
- 作为模型系统,利用了具有不同交叉链密度的无溶剂环氧聚合物网络.
- 采用剪切风学来测量MPa范围内的存储模量 (G).
- 应用Brillouin光谱法 (BLS) 来确定GPa范围内GHz频率的纵向模量 (M').
主要成果:
- 储存模块 (G') 与纵向模块 (M') 相比,与交叉链密度 (~3.5x) 相比,显著增加.
- 与其前身相比,在交联环氧网络中观察到意想不到的快速超音速分散.
- 与幻象网络模型相关联的G'和M'与伍德的混合规则的反向规则.
结论:
- G'和M'对交叉链接的独特反应突显了多尺度弹性测量的重要性.
- BLS提供了一种非接触式的光学方法,用于探测软材料的GHz频率机械性能.
- 这些发现鼓励进一步研究,以弥合跨不同频率模式的软材料弹性的理解.
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