Yamato Masafumi, Kimura Tsunehisa
Department of Applied Chemistry, Tokyo Metropolitan University,1-1 Minami-ohsawa, Hachioji, Tokyo 192-0397, Japan.
Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
Polymers (Basel). 2020 Jul 3;12(7):1491. doi: 10.3390/polym12071491.
Currently, materials scientists and nuclear magnetic resonance spectroscopists have easy access to high magnetic fields of approximately 10 T supplied by superconducting magnets. Neodymium magnets that generate magnetic fields of approximately 1 T are readily available for laboratory use and are widely used in daily life applications, such as mobile phones and electric vehicles. Such common access to magnetic fields-unexpected 30 years ago-has helped researchers discover new magnetic phenomena and use such phenomena to process diamagnetic materials. Although diamagnetism is well known, it is only during the last 30 years that researchers have applied magnetic processing to various classes of diamagnetic materials such as ceramics, biomaterials, and polymers. The magnetic effects that we report herein are largely attributable to the magnetic force, magnetic torque, and magnetic enthalpy that in turn, directly derive from the well-defined magnetic energy. An example of a more complex magnetic effect is orientation of crystalline polymers under an applied magnetic field; researchers do not yet fully understand the crystallization mechanism. Our review largely focuses on polymeric materials. Research topics such as magnetic effect on chiral recognition are interesting yet beyond our scope.
目前，材料科学家和核磁共振光谱学家能够轻松获得由超导磁体提供的约10 T的高磁场。能产生约1 T磁场的钕磁铁很容易获得，可用于实验室，并且广泛应用于日常生活中，如手机和电动汽车。这种对磁场的普遍获取——这在30年前是难以想象的——帮助研究人员发现了新的磁现象，并利用这些现象来处理抗磁性材料。尽管抗磁性广为人知，但直到最近30年，研究人员才将磁处理应用于各类抗磁性材料，如陶瓷、生物材料和聚合物。我们在此报告的磁效应很大程度上归因于磁力、磁转矩和磁焓，而这些又直接源自明确的磁能。一个更复杂的磁效应的例子是结晶聚合物在施加磁场下的取向；研究人员尚未完全理解其结晶机制。我们的综述主要集中在聚合物材料上。诸如磁对手性识别的影响等研究主题很有趣，但超出了我们的范围。
