具有不同烯酸含量的NBR/PVC混合物的相隔结构使用STEM-EDS映射分析进行了调查
Yuka Komori1,2, Aoi Taniguchi2, Haruhisa Shibata1
1Materials Engineering R & D Division, DENSO CORPORATION, Kariya-shi 448-8661, Aichi, Japan.
Polymers
|August 26, 2023
概括
这项研究检查了乙烯/聚乙烯化物混合物. 较高的烯酸含量增加了混合混合性,改变了相隔结构.
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:
- 乙烯 (NBR) 和聚乙烯 (PVC) 混合物被广泛使用.
- 了解它们的相隔结构对于定制材料特性至关重要.
- 在NBR中的烯酸 (AN) 含量对混合物形态的影响需要详细研究.
研究的目的:
- 为了研究NBR/PVC混合物的相隔结构,在NBR中含有不同的AN含量.
- 通过使用动态机械分析和显微镜,将混合性变化与AN含量相关联.
- 分析混合物中的域形态和组件分布.
主要方法:
- 动态机械分析 (DMA) 用于测量tan delta峰值.
- 扫描传输电子显微镜 (STEM) 与能量分散X射线光谱 (EDS) 结合用于元素分析.
- 阶段分离和组件分布的表征.
主要成果:
- 在低AN含量 (18.0%) 的两个明显的tan delta峰值表明了显著的相位分离.
- 在较高的AN含量 (29.0%和33.5%) 的单个宽棕色三角洲峰值表明混合性增加.
- STEM-EDS揭示了具有较低AN含量的大型PVC域和具有较高AN含量的纳米级分散域.
- 增加AN含量减少了PVC领域和NBR矩阵之间的度差异.
结论:
- 在NBR中较高的AN含量提高了NBR/PVC混合物的混合性.
- AN的内容显著影响了相隔形态和组件分布.
- 观察到的机械性能和形态学的变化与聚合物混合物的混合性增加相一致.
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