COMPATIBILITY AND PHASE-BEHAVIOR IN CHARGED POLYMER SYSTEMS AND IONOMERS

In this paper we study the phase behavior of binary blends of charged macromolecules and ionomers. General formulas are given for the density fluctuations in the terms of the monomer and charge structure factors of the individual components, and the stability of the system is examined in detail. Coulombic and ionic interactions among the chains are shown to lead to a renormalization of the classical Flory-Huggins parameters χo and χF. The main result is that polyelectrolytes of opposite charges are always compatible, due to the strong long-range Coulombic interaction, which can always overcome the thermodynamic repulsion. In ionomers, where the charges or dipoles are separated by a certain arc length along the chain, a micro phase separation can occur on length scales determined by the charge/ion distribution. © 1990, American Chemical Society. All rights reserved.