Effect of polymer architecture on the miscibility of polymer/clay mixtures

Abstract

Using self-consistent field calculations, we investigate the interactions between two closely-spaced surfaces and the surrounding polymer melt. Short surfactants are terminally anchored to each of the surfaces. The coated substrates model organically-modified clay crystallites (sheets). Holding the polymer length fixed, we systematically vary the architecture of the chains, from linear to ten-armed stars. We then calculate the free energy of the system as the surfaces are prised apart in the different polymer melts. Through these calculations, we isolate conditions that drive these chains to penetrate the gap between the surfaces. The studies provide guidelines for tailoring the miscibility and morphology of the mixture and thus, fabricating thermodynamically stable polymer/clay composites. © 2000 Society of Chemical Industry