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聚乙烯的平均磁性异构性在聚合物自组自聚乙烯糖醇) -b-聚乙烯自组的聚合物体中

Roger S M Rikken^1,2, Sandra Kleuskens^1,2, Loai K E A Abdelmohsen²

¹High Field Magnet Laboratory (HFML - EMFL), Radboud University, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands. hans.engelkamp@ru.nl.

|December 20, 2023

概括

研究人员量化了聚合物二磁性异性质在聚合体膜中. 这种新方法描述了聚合物和聚合物聚合物,显示了聚合物与磁场垂直对齐,有可能用于低场应用.

科学领域:

软物质物理学软物质物理学
聚合物科学聚合物科学
材料的表征材料的表征.

背景情况:

聚合物的二磁性异性质是一种新兴的特征化技术.
目前对聚合物二磁性质的定量描述有限.
聚合体为研究聚合物在封闭环境中的行为提供了一个模型系统.

研究的目的:

量化测量聚乙烯 (PS) 重复单元在聚乙烯-聚乙烯 (PEG-PS) 聚合体膜中的二磁性异构性.
为了研究PS长度和制备方法对二磁性异性质的影响.
建立单个聚合物重复单元的磁性和整体聚合体结构之间的联系.

主要方法:

利用磁双折射来测量PS重复单位的二磁性异构性 (Δχ) .
采用了一个理论模型,将重复单元的磁性与聚合物相联系起来.
合成的PEG-PS聚合体具有不同的PS长度和制备技术.

主要成果:

所有测量的Δχ^PS值均为负值,表明聚合物对准垂直于应用磁场.
发现PS重复单位的二磁性异构性大约为10-12m3mol-1,在不同的聚合体形状和PS长度中一致.
测量出的异构性约为理论最大值的1%,归因于随机聚合物卷轴.

结论:

无论聚合体的形状或PS的长度如何,PS重复单元的二磁性异性质是一致的,这表明了类似的聚合物组织.
相对较低的异构性表明通过增加聚合物排序来增强显著的增强潜力.
进一步订购聚合物可以使聚合体在较低磁场的反应,可能使用永久磁铁的实际应用.

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