Synthesis Of Glycidyl Methacrylate Based Block Copolymers With Self-Catalysis And Self-initiation Behaviors Via Atom Transfer Radical Polymerization

Poly(glycidyl methacrylate) or PGMA-based polymers are particularly attractive beause of their reactive pendant oxirane rings. In this thesis, narrow polydispersity glycidyl methacrylate (GMA) based di- and tri-block copolymers, with self-catalysis and self-initiation behaviors by incorporation of 2-(diethylamino) ethyl methacrylate (DEA) blocks, were synthesized via ambient temperature atom transfer radical polymerization (ATRP). The kinetic characters of ATRP of DEA, 2-(dimethylamino) ethyl methacrylate(DMA), and GMA respectively and as well as the characters of the copolymerization of DEA and GMA had been analyzed respectively through 1H NMR and GPC testing. The reactivity both in oxirane ring opening addition reaction and in post-cure oxirane ring opening cross-linking of these block copolymers was investigated.The results of kinetic study of ATRP of DEA, DMA, and GMA using Cu(I)Br/bpy complexes as catalyzer system, using ethyl 2-bromoisobutyrate and ethylene bis(2-bromoisobutyrate)as initiators in anhydrous ethyl acetate showed the characteristics of controlled/"living"polymerization.The results of the investigation on the stability of pendent oxirane rings in tertiary amine environment demonstrated that the reactivity of pendent oxirane rings was strongly dependant on the nucleophilicity and steric hindrance of tertiary amine derivatives . This facilitated the synthesis of narrow polydispersity block copolymers of GMA and DEA via sequential monomer addition atom transfer radical polymerization, particularly for polymerization of GMA monomer at ambient temperature.The results of the investigation about the reactivity both in oxirane ring opening addition reaction and in post-cure oxirane ring opening cross-linking of these block copolymers which were investigated evidenced by 1H NMR studies confirmed the self-catalysis behavior in oxirane ring opening addition reaction and self-initiation behavior in post-cure oxirane ring opening cross-linking of these block copolymers . The results also demonstrated that the reactivity of pendent oxirane rings was strongly dependant on the nucleophilicity and steric hindrance of tertiary amine moieties and temperature. The mechanism of nucleophilic ring opening addition reaction of oxirane rings diethyl amine in the presence of tertiary amine was presented.