Development of micro/macro-scale dynamic characterization system and its application to polymer gel science

聚合物凝胶由网络聚合物链和溶剂两部分组成。此外，凝胶中通常含有第三组分，例如低分子化合物或聚合物。从各种物理和化学性质的角度来看，聚合物凝胶引起了人们的极大关注。例如，随着溶剂组成、pH、离子强度和温度的变化，水电解质凝胶的体积会发生显著变化。它们在施加电场时会收缩。此外，水膨胀的聚合物凝胶可以将化学能转化为机械能。这些性质导致了聚合物研究的活力，并引起了人们对聚合物凝胶体系的各种兴趣。为了开发新的聚合物材料，在先进的聚合物科学技术的基础上进行了聚合物凝胶设计。聚合物凝胶的性质与其结构和动力学密切相关。在这种情况下，阐明聚合物的结构和动力学的方法对于制定可靠的聚合物凝胶设计和开发新型先进的聚合物凝胶是重要的，对聚合物科学也是重要的。在这样的背景下，我们成功地研制了高场梯度自旋回波核磁共振系统和核磁共振成像系统，能够测定10^-10-10^-11 cm^2/S的极小扩散系数和自旋密度和扩散系数分布的三维图像，并阐明了聚合物凝胶的结构和动力学。

Polymer gels consist of two components of network polymer chains and solvent. Further, a third component such as a low molecular-weight compound or polymer is often contained in the gels. Polymer gels have attracted considerable attention from the point-of-view of various physical and chemical properties. For example, hydroelectrolyte gels show a dramatic change in volume in response to change in solvent composition, pH, ionic strength and temperature. They contract upon application of an electric field. Further, water-swollen polymer gels can convert chemical energy into mechanical energy. These properties lead to the vitality of polymer research and development of a diversity of interests in polymer gel systems. In order to develop new polymer materials, polymer gel design has been performed on the basis of advanced polymer science and technology. The properties of polymer gels are closely related to their structures and dynamics. From such situations, the establishment of methods for elucidating the structures and dynamics is important for making reliable polymer gel design and developing new advanced polymer gels and also is important for polymer science. From such a background, we have successfully developed by high field-gradient spin-echo(PFGSE) NMR system and NMR imaging system capable of determining very small diffusion coefficients of 10^-10 - 10^-11 cm^2/s and three-dimensional image pattern about spin density and diffusion coefficient distribution, and have elucidated structure and dynamics of polymer gels.