Microphase Separation in Mixtures of Block Copolymers with the Corresponding Homopolymers: Zeroth Approximation

Abstract

The conditions necessary for microphase separation in mixtures of block copolymers with one of the corresponding homopolymers are developed as a function of block copolymer composition, molecular weight, number of blocks per molecule, interaction parameter between the corresponding homopolymers, and molecular weight of the added homopolymer. These conditions for microphase separation are compared with the conditions necessary for ordinary phase separation in mixtures of random copolymers with one of the corresponding homopolymers. Both the amount and the molecular weight of added homopolymer have a larger effect on the conditions for phase separation in random-copolymer-homopolymer mixtures than they have on the conditions for microphase separation in block copolymer-homopolymer mixtures.