NONEQUILIBRIUM MORPHOLOGIES OF A DIBLOCK COPOLYMER OF POLYISOPRENE AND POLY(n-BUTYL METHACRYLATE).

This paper is concerned with the unusually wide variety of morphologies which can be obtained from a diblock copolymer of polyisoprene and poly(n-buty methacrylate). In experiments, the copolymer was synthesized using homogeneous anionic polymerization methods. Cast film samples of copolymers were examined by means of electron microscopy. The unusual morphologies exhibited by the polyisoprene/poly(n-butyl methacrylate) diblock may arise in part from the structure of the n-butyl methacrylate repeat unit. The polar groups in the ester moiety cause this methacrylate polymer to prefer polar solvents and to reject solvents of the nonpolar hydrocarbon variety; on the other hand, the n-butyl side-group of this monomer is likely to have a compatibilizing effect in the presence of hydrocarbons, including polyisoprene.