Improved Compatibilization of Immiscible Homopolymer Blends Using Copolymer Mixtures

Abstract

An analytical self-consistent-field theory and numerical self-consistent-field calculations are used to study the efficiency of binary mixtures of di- and comb block copolymers in reducing the interfacial tension between two immiscible homopolymers. In particular, we consider: 1) the mixture of diblock copolymers of two different molecular weights and 2) the mixture of diblock and comb copolymers, in which we vary the molecular weights for copolymers and the number of teeth for the comb. For the mixture of diblock copolymers of two different molecular weights, we show that the longer component controls the interfacial tension. For the mixture of the diblock and comb copolymers, we found that at a specific relationship between molecular weights of the copolymers and the number of teeth of the comb, the mixture can be more efficient than either of the pure components. The findings are important for tailoring the properties of immiscible blends.