FROM MEAN-FIELD TO DIFFUSION-CONTROLLED KINETICS - CONCENTRATION-INDUCED TRANSITION IN REACTING POLYMER-SOLUTIONS

被引：32

作者：

OSHAUGHNESSY, B

机构：

[1] Department of Chemical Engineering, Materials Science and Mining Engineering, Columbia University, New York

来源：

PHYSICAL REVIEW LETTERS | 1993年 / 71卷 / 20期

关键词：

D O I：

10.1103/PhysRevLett.71.3331

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We study irreversible interpolymeric reaction rates k in polymer solutions as a function of concentration phi. At high dilution, kinetics obey mean field theory, and screening of excluded-volume repulsions as phi increases results in a growth, k is similar to phi3g/4, where g is the monomer contact exponent. Screening effects cause a transition to diffusion-controlled kinetics at a value phi**, beyond which (for entangled solutions) k decreases as k is similar to phi-(5/8+gamma), gamma being the entanglement exponent. Thus k is peaked at phi** which, in agreement with experiment, is distinct from the overlap threshold.

引用

页码：3331 / 3334

页数：4