Miscibility of solution-chlorinated polyethylene with poly(α-methylstyrene-co-acrylonitrile)

Statistical copolymers of α‐methylstyrene and acrylonitrile (MSAN) form single‐phase blends with solution‐chlorinated polyethylene within a restricted composition range, even though no combination of the corresponding homopolymers is miscible. The phase behavior can be successfully described using the general mean‐field expression which predicts miscibility on the basis of the intramolecular interactions of the comonomers. By deriving the absolute value of one of the six system interactions from a subsidiary determination of the miscibility limits of poly (methylmethacrylate) in MSAN, values of all the remaining interaction parameters have been determined using a novel phase boundary‐fitting technique.