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Development of a NMR Probe for the Super-High Magnetic-Field Gradient Spin-Echo and its Application to Polymer Systems

超高磁场梯度自旋回波核磁共振探针的研制及其在聚合物体系中的应用

基本信息

批准号：
01850196
负责人：
NOSE Takuhei
金额：
$ 7.04万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B).
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

项目摘要

1. Development of a NMR probe for the super-high magnetic-field gradient spinecho (FGSE-NMR)(1) We have succeeded in construction of the probe with following specifications.Maximum of magnetic-field gradient 600G/cmSample size diameter 5mm x length 8mmPulse width 0.03-50msPulse interval 5-600msGenerated magnetic-field gradient was calibrated against applied electric current, and reliability of the measurement was confirmed. Available ranges of pulse-width and pulse-interval were determined by taking the effect of residual magnetic field into account. The maximum gradient attained here is the highest in reported values in the polymer field.2. Application to polymer systemsApplicability of the FGSE-NMR method with this probe was demonstrated through the following experimental studies on polymer dynamics.(1) Diffusion of polymer chains in poly (dimethylsiloxane) mixturesThe FGSE-NMR could measure diffusion coefficient for each component in polymer mixtures separately. Role of hydrodynamic interactions in chain diffusion in melts was revealed.(2) Diffusion of polymer chains dissolved in microdomains of blockcopolymers Was measured diffusion coefficient of B-polymer chains which were dissolved in microdomains of A-B and A-B-A type block copolymers. Diffusion behavior of tracer chains are controlled by location of the dissolved chains in the domain.(3) Diffusion of water molecules in polymer gelsDiffusion coefficient of water molecules in a poly (methacrylic acid) hydro-gel was measured as a function of the degree of swelling, and diffusion of the free water was found to be slower at the higher degrees of swelling.

1. 超高磁场梯度脊柱核磁共振探针（FGSE-NMR）的开发（1）我们已成功构建了以下规格的探针。最大磁场梯度600G/cm样品尺寸直径5mm x 长度8mm脉冲宽度0.03-50ms脉冲间隔5-600ms产生的磁场梯度根据施加的电流进行校准，并且可靠性测量得到确认。考虑剩磁磁场的影响，确定了脉冲宽度和脉冲间隔的可用范围。这里达到的最大梯度是聚合物领域报道值中最高的。2．在聚合物体系中的应用通过以下聚合物动力学实验研究证明了使用该探针的FGSE-NMR方法的适用性。（1）聚二甲基硅氧烷混合物中聚合物链的扩散FGSE-NMR可以分别测量聚合物混合物中每种组分的扩散系数。揭示了流体动力学相互作用在熔体链扩散中的作用。(2)溶解在嵌段共聚物微区中的聚合物链的扩散测量了溶解在A-B型和A-B-A型嵌段共聚物微区中的B-聚合物链的扩散系数。示踪链的扩散行为由域中溶解链的位置控制。(3)聚合物凝胶中水分子的扩散测量聚(甲基丙烯酸)水凝胶中水分子的扩散系数作为溶胀度的函数，发现溶胀度越高，自由水的扩散越慢。