在复合材料中的界面聚甲基烯酸) -d) 3) 的细分动力学,通过乳NMR光谱学
1Department of Chemistry and Materials Research Center, University of Missouri-Rolla, Rolla, MO 65409-0010, USA.
Journal of the American Chemical Society
|July 18, 2001
概括
核磁共振显示,上超薄的聚甲酸层在接口上表现出改变的细分移动性. 用聚合物 (如聚乙烯) 进行覆盖,会降低这种流动性,其影响取决于覆盖层.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 表面科学是一门学科.
背景情况:
- 了解聚合物接口对于设计先进复合材料至关重要.
- 聚合物在接口上的行为与它们的散装性质有很大的不同.
研究的目的:
- 为了研究在二氧化接口上的超薄聚甲基烯酸-d(3) (PMA-d(3) 的细分移动性.
- 确定不同分子重量的不同覆盖层聚合物 (聚乙烯和聚甲酸) 对界面流动性的影响.
主要方法:
- 用固态四极回声NMR光谱学研究了接口动力学.
- 复合样本是通过用化聚钢 (PS) 和化聚甲酸 (PMA) 覆盖层热压制PMA-d(3) /制的.
主要成果:
- 在空气-聚合物-二氧化接口上,一些PMA-d (3) 段显示出比散装PMA-d (3) 更高的移动性.
- 用未标记的聚合物涂层减少了接口PMA-d的细分移动性.
- 流动性下降的顺序是:低分子量PMA>高分子量PMA>PS,与高层聚合物流动性相关.
结论:
- 聚合物界面流动性受到相邻层的显著影响.
- 覆盖层聚合物的性质和可移动性决定了聚合物界面段的限制程度.
- 这些发现提供了对复合材料接口工程的见解.
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