The radical polymerization of spiro-cyclic monomer 8-methylene-1,4-dioxaspiro[4,5]deca-6,9-diene(MDOSD) is known to proceed via oxy radical mechanism. To investigate this mechanism further copolymerization with various monomers were carried out. MDOSD was prepared from 1,4-dioxaspiro[4,5]deca-6,9-diene-8-one(DOSDO) by Wittig reaction. Polymerization of MDOSD was driven by the aromatization energy and proceeded mainly in 1,9-type ring-opening polymerization mode. MDOSD was copolymerized with styrene, methyl methacrylate, vinyl acetate by radical initiator AIBN and different conversions were observed. The structures of MDOSD copolymers were confirmed by NMR and IR. In the copolymerization with styrene or MMA, high molecular weight polymers were obtained. Conversion of copolymerization with VA was lower than that of MDOSD homopolymerization. Polymerization of MDOSD-co-styrene polymer was occurred through mainly 1,9-type ring-opening polymerization mode. However, polymerization of MDOSD with methyl methacrylate showed complicated polymerization mode of 1,4-type and 1,9-type ring-opening polymerization. Copolymerization with vinyl acetate produced mainly VA homopolymer and small amount of copolymer was obtained.
