Preparation of Block Copolymer of ε-Caprolactone with Living Polystyrene

Abstract

Abstract ε-Caprolactone was polymerized by using living polystyrene prepared by means of an anionic polymerization technique. A gross polymer was elution-fractionated into four fractions which were methanol-soluble low-molecular-weight polyester, high-molecular-weight polyester, a small amount of polystyrene and polystyrene-polyester block copolymer. Both yields and molecular weights of block copolymers were observed to be higher in benzene than in tetrahydrofuran. Formation of block copolymers was concluded from the results of an elementary- and infrared analyses and turbidometry. Polymerization mechanism of ε-caprolactone is discussed.