Thermodynamics of Random Copolymer Mixtures by Sans

Abstract

A test of the theory of random copolymer miscibility is described in this paper. A series of random ethylene-butene copolymers were made by the saturation of polybutadienes of varying vinyl content, and the interactions in blends of these copolymers were measured by small angle neutron scattering (SANS). It was found that the standard random copolymer theory does not describe the data in that the interaction parameters were not proportional to the square of the difference in the compositions of the component copolymers. Rather, blends of ethylene rich copolymers had lower χ values than corresponding butene rich blends.