Bordi F, Cametti C, Gili T
Dipartimento di Fisica, Università di Roma La Sapienza, Rome, Italy.
Phys Rev E Stat Nonlin Soft Matter Phys. 2003 Jul;68(1 Pt 1):011805. doi: 10.1103/PhysRevE.68.011805. Epub 2003 Jul 29.
The effects of added salt on the electrical conductivity behavior of a polyelectrolyte solution are described in light of the scaling approach recently proposed by Dobrynin and Rubinstein [Macromolecules 28, 1859 (1995); 32, 915 (1999)], taking into account the influence of the solvent quality factor. The coupling between the conformation of the chain and the local charge distribution, giving rise to different conductometric behaviors, has been investigated under different conditions, in a wide concentration range of added salt. The polyion equivalent conductances lambda(p) have been evaluated in different concentration regimes for a hydrophilic polyion in good solvent condition and compared with the experimental values obtained from electrical conductivity measurements. The agreement is rather good in the wide range of concentration of the added salt investigated. In the case of poor solvent conditions, we find the appropriate expressions for the electrical conductivity when the polyion chain consists into collapsed beads alternating with stretched segments in the framework of the necklace globule model.
根据多布林宁和鲁宾斯坦最近提出的标度方法[《大分子》28, 1859 (1995); 32, 915 (1999)]，考虑到溶剂质量因子的影响，描述了添加盐对聚电解质溶液电导率行为的影响。在添加盐的宽浓度范围内，研究了在不同条件下链构象与局部电荷分布之间的耦合，这种耦合导致了不同的电导行为。对于处于良溶剂条件下的亲水性聚离子，在不同浓度范围内评估了聚离子当量电导λ(p)，并与通过电导率测量获得的实验值进行了比较。在所研究的添加盐的宽浓度范围内，两者吻合得相当好。在不良溶剂条件下，当聚离子链在项链状球模型框架内由塌缩的珠粒与伸展的链段交替组成时，我们找到了电导率的合适表达式。
