EFFECT OF COPOLYMER ARCHITECTURE ON THE EFFICIENCY OF COMPATIBILIZERS

We use analytical arguments and numerical self-consistent field (SCF) calculations to calculate the interfacial tension, gamma, for a system of AB copolymers localized at the interface between two immiscible ho mopolymers, A and B. In particular, we fix the molecular weights of th e copolymers but vary their architecture from diblock, star, and vario us comb copolymers. The results from both methods show that diblock co polymers are the most efficient at reducing gamma. We also observe tha t at fixed molecular weight (N), as the number of teeth (n) is increas ed, the comb becomes significantly less efficient and the disparity be tween combs and diblocks grows larger. However, when we compare combs and diblocks with different molecular weights, we observe a trade-off between N and n. In particular, long combs with multiple teeth are mor e efficient than short diblocks. These studies allow us to predict the reduction in interfacial tension produced by a wide variety of copoly mers and thereby permit a rational design of effective compatibilizers .