Effect of Polymer Melt Memory as Studied by Nuclear Magnetic Resonance

核磁共振研究聚合物熔体记忆效应

• 批准号: 13650956
• 负责人: KIMURA Tsunehisa
• 金额: $ 2.5万
• 依托单位: Tokyo Metropolitan University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650956/
• 关键词: NMR; Magnetic Alignment; Polymer; Molecular Weight Dependence; Structure Formation

A high-temperature NMR probe became repaired this year and the in-situ NMR measurements for poly(ethylene oxide) (PEO) and paraffin were carried out during the heating and cooling processes. The PEO sample of Mn=4,600 did not show any difference between the starting powder pattern and the spectrum obtained after heating followed by cooling, indicating no alignment. But the sample of Mn=2,000 exhibited the difference, indicating magnetic alignment.The spectrum of paraffin starts with a powder pattern typical of a σ_<11>, σ_<22>, σ_<33> system, then changed to σ_<11> = σ_<22> type pattern upon heating. This is due to the phase change to the hexagonal phase. Upon melting, the broad peak changed to a narrow one. During the cooling process, the melt passes through a hexagonal phase at which the magnetic alignment was indicated by the reduction of the high-field σ_<33> component. This means that the chain (33 direction) aligned perpendicular to the magnetic field. This is consistent with the previous results by X-ray.

今年修复了一个高温核磁共振探针，并在加热和冷却过程中对聚环氧乙烷（PEO）和石蜡进行了原位核磁共振测量。Mn= 4600的PEO样品的起始粉末图案与加热后冷却后得到的光谱没有任何差异，说明没有对齐。但Mn= 2000的样品表现出这种差异，表明磁性排列。石蜡的光谱开始表现为σ_<11>、σ_<22>、σ_<33>型，加热后转变为σ_<11> = σ_<22>型。这是由于相变到六边形相。融化后，宽峰变成窄峰。在冷却过程中，熔体经过一个六角形相，高场σ_<33>分量的减小表明熔体的磁向。这意味着链（33方向）垂直于磁场排列。这与先前的x射线结果一致。

项目成果

M.Yamato, T.Kimura: "Magnetic Orientation of Polyesterether"Trans. MRS-J. (印刷中). (2002)

M.Yamato、T.Kimura：“聚酯醚的磁取向”Trans（印刷中）。

H.Aoki, M.Yamato, T.Kimura: "Magnetic Alignment of Poly(carbonate)"Chemistry Letters. 11. 1140-1141 (2001)

H.Aoki、M.Yamato、T.Kimura：“聚碳酸酯的磁性排列”化学快报。

F.Kimura, T.Kimura et al.: "Magnetic Alignment of Poly(ethylene oxide)"Trans. MRS-J. (印刷中). (2002)

F.Kimura、T.Kimura 等人：“聚环氧乙烷的磁性排列”MRS-J（出版中）。