Atom transfer radical polymerization (ATRP) has achieved widespread use in living polymerization. However, until now there hasbeen little report that macroinitiators initiate polymerization in different catalytic systems. The preparation of bromine-terminatedpolymethyl methacrylate (PMMA-Br) and chlorine-terminated PMMA (PMMA-Cl) were carried out via reverse atom transferradical polymerization (RATRP). The PMMA with halogen termination and narrow polydispersity (Mn = 12,000–15,000 g/mol,Mw/Mn = 1.1–1.2) were used as macroinitiators. The block copolymer of polymethyl methacrylate and polyacrylonitrile (PMMAb-PAN) was prepared in different catalytic systems through normal ATRP. The analyses of the 1H NMR showed that the PMMAprepared by RATRP were end-functionalized by halogen atoms, demonstrated the activities of the PMMA macroinitiators. Themolecular weight and polydispersity index (PDI) of the polymers were analyzed using gel permeation chromatography (GPC). The results indicated that the block polymers that the molecular weight of the block copolymer after chain extension has increasedsignificantly and the molecular weight distribution is narrow (Mn = 17,000–25,000 g/mol, Mw/Mn = 1.1–1.3). The kinetics ofthese polymerization processes were studied as a function of monomers to the macroinitiator molar ratio. It was found that thepolymerizations in different catalytic systems coincidence first-order kinetics with respect to monomers.
Atom transfer radical polymerization (ATRP) has achieved widespread use in living polymerization. However, until now there hasbeen little report that macroinitiators initiate polymerization in different catalytic systems. The preparation of bromine-terminatedpolymethyl methacrylate (PMMA-Br) and chlorine-terminated PMMA (PMMA-Cl) were carried out via reverse atom transferradical polymerization (RATRP). The PMMA with halogen termination and narrow polydispersity (Mn = 12,000–15,000 g/mol,Mw/Mn = 1.1–1.2) were used as macroinitiators. The block copolymer of polymethyl methacrylate and polyacrylonitrile (PMMAb-PAN) was prepared in different catalytic systems through normal ATRP. The analyses of the 1H NMR showed that the PMMAprepared by RATRP were end-functionalized by halogen atoms, demonstrated the activities of the PMMA macroinitiators. Themolecular weight and polydispersity index (PDI) of the polymers were analyzed using gel permeation chromatography (GPC). The results indicated that the block polymers that the molecular weight of the block copolymer after chain extension has increasedsignificantly and the molecular weight distribution is narrow (Mn = 17,000–25,000 g/mol, Mw/Mn = 1.1–1.3). The kinetics ofthese polymerization processes were studied as a function of monomers to the macroinitiator molar ratio. It was found that thepolymerizations in different catalytic systems coincidence first-order kinetics with respect to monomers.