Foster K R, Cheever E, Leonard J B, Blum F D
Biophys J. 1984 May;45(5):975-84. doi: 10.1016/S0006-3495(84)84242-3.
A variety of transport properties have been measured for solutions of the water soluble polymer poly(ethylene oxide)(PEO) with molecular weights ranging from 200 to 14,000, and volume fractions ranging from 0-80%. The transport properties are thermal conductivity, electrical conductivity at audio frequencies (in solutions containing dilute electrolyte), and water self-diffusion. These data, together with dielectric relaxation data previously reported, are amenable to analysis by the same mixture theory. The ionic conductivity and water self-diffusion coefficient, but not the thermal conductivity, are substantially smaller than predicted by the Maxwell and Hanai mixture relations, calculated using the known transport properties of pure liquid water. A 25% (by volume) solution of PEO exhibits an average dielectric relaxation frequency of the suspending water of one half that of pure water, with clear evidence of a distribution of relaxation times present. The limits of the cumulative distribution of dielectric relaxation times that are consistent with the data are obtained using a linear programming technique. The application of simple mixture theory, under appropriate limiting conditions, yields hydration values for the more dilute polymer solutions that are somewhat larger than values obtained from thermodynamic measurements.
已对分子量范围为200至14,000且体积分数范围为0 - 80%的水溶性聚合物聚环氧乙烷（PEO）溶液的多种传输性质进行了测量。这些传输性质包括热导率、音频频率下的电导率（在含有稀电解质的溶液中）以及水的自扩散。这些数据，连同先前报道的介电弛豫数据，都适合用相同的混合理论进行分析。离子电导率和水的自扩散系数，但不包括热导率，比使用纯液态水已知传输性质通过麦克斯韦和花井混合关系预测的值要小得多。25%（体积）的PEO溶液中悬浮水的平均介电弛豫频率是纯水的一半，且有明显证据表明存在弛豫时间分布。使用线性规划技术获得了与数据一致的介电弛豫时间累积分布的极限。在适当的极限条件下应用简单混合理论，对于较稀聚合物溶液可得到比通过热力学测量获得的值稍大的水合值。
