Static inhomogeneities and dynamics of swollen and reactor-batch polymer gels
Static inhomogeneities and dynamics of swollen and reactor-batch polymer gels
复制标题
溶胀和反应器批次聚合物凝胶的静态不均匀性和动力学
DOI：
10.1063/1.480631
复制
发表时间：
2000
影响因子：
4.4
通讯作者：
Y. Shiwa
中科院分区：
文献类型：
--
作者：
M. Shibayama;Y. Shirotani;Y. Shiwa
用动态光散射法研究了聚N-异丙基丙烯酰胺（NIPA）在水中的溶胀凝胶和反应器-间歇凝胶随聚合物体积分数φ的变化。来自这些凝胶的散射强度显示出依赖于样品位置的强烈强度波动。集合（即，位置）的平均散射强度，Δ I Δ E，对于在不同初始单体浓度下制备的所有凝胶，通过溶胀而增加，表明通过溶胀而增加的静态不均匀性。另一方面，动态分量，例如，热波动的强度分量IF由于膨胀而降低。集体扩散系数D随φ的增大而增大，并随膨胀而增大。讨论了凝胶的静态不均匀性和动态不均匀性的物理意义。此外，扩散系数的浓度依赖性作为φ的函数进行了讨论。
The dynamic light scattering study has been carried out on swollen and reactor-batch gels of poly(N-isopropylacrylamide) (NIPA) in water as a function of polymer volume fraction, φ. The scattered intensity from these gels showed strong intensity fluctuations dependent on the sample position. The ensemble (i.e., position) average scattered intensity, 〈I〉E, increased by swelling for all gels prepared at different initial monomer concentrations, indicating an increase of the static inhomogeneities by swelling. On the other hand, the dynamic component, e.g., the intensity component of the thermal fluctuations, IF, decreased by swelling. The collective diffusion coefficient, D, increased with increasing φ and by swelling. The physical meaning of the static inhomogeneities and the dynamics of gels are discussed. Furthermore, the concentration dependence of the diffusion coefficient is discussed as a function of φ.