在聚合物稳定磁性纳米复合材料中的结构相互作用
Gauri M Nabar1, Abhilasha V Dehankar1, Elizabeth Jergens1
1William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, 151 W. Woodruff Ave., Columbus, OH 43210, USA. winter.63@osu.edu.
Soft matter
|April 22, 2024
概括
外部磁场可以对超偏磁性氧化铁纳米粒子 (SPION) 聚合物进行命令. 在合成过程中应用磁场可以保存SPION链结构,而在合成后的应用会微妙地重新排序它们,从而影响磁性.
科学领域:
- 纳米技术纳米技术
- 材料科学 材料科学 材料科学
- 生物物理学的生物物理.
背景情况:
- 超偏磁铁氧化物纳米粒子 (SPIONs) 具有独特的纳米级磁性.
- 对于各种应用,SPION聚合物可以形成有序结构,具有可调整的复合材料特性.
- 外界磁场对SPION聚合物的结构和特性的影响仍然不完全理解.
研究的目的:
- 研究外部磁场对聚合物稳定型SPION聚合物的结构,排序和磁性质的影响.
- 确定磁场应用的时间 (合成期间与合成后) 如何影响SPION总体特征.
- 探索磁场的潜力作为一个工具来定制SPION纳米复合材料的特性.
主要方法:
- 在有或没有磁场的情况下合成SPION聚合物的合成,以及合成后的磁场暴露.
- 使用传输电子显微镜 (TEM),小角度X射线散射 (SAXS),超导量子干扰装置 (SQUID) 分析和差分扫描热度计 (DSC) 的表征.
主要成果:
- 外部磁场诱导SPION聚合物的排序,影响结构,SPION间距离和复合玻璃过渡温度 (Tg).
- 在合成过程中使用磁场促进了SPION链聚合物的保存,即使在移除磁场后.
- 合成后的磁场应用导致了微妙的内部重新排序,由增加的阻塞温度 (TB) 证明,SAXS或TEM无法检测到.
结论:
- 磁场应用是影响聚合物稳定型SPION纳米复合材料结构和磁性特性的关键因素.
- 磁场暴露的时间在很大程度上决定了由此产生的聚合物排序和特性.
- 磁场提供了一种简单有效的方法来精确控制和调整SPION纳米复合材料的特性.
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