Modifications of simple models of polymer blend compatibilization using block copolymer

Abstract

Polymer blends can be compatibilized using block and graft copolymers with blocks identical to, miscible with, or adhering to related components of the blend. The relatively simple models of compatibilized blends published in our preceding papers following up on the work of Leibler and its modification by Retsos, based on the comments of Noolandi, have now been extended. Our analysis of the mean field formula for a decrease in the interfacial tension by Noolandi and Hong resulted in further modification. This modification provides a higher amount of copolymer in the interfacial region and higher compatibilization efficiency than models used in our previous papers. In contrast to previous theories, it predicts maximum compatibilization efficiency for copolymer blocks somewhat shorter than the homopolymers. With respect to the Flory–Huggins interaction parameter, this calculated maximum reaches its lowest value for a certain value of the interaction parameter.