Atom Transfer Radical Copolymerization of St and DMF using EBP as initiator, CuBr/ N, N, N', N'', N'' - pentamethyldiethylenetriamine (PMDETA) as a catalyst system was carried out successfully. The results showed that when conversion was below 60%, In ([M]0/[M]) had a good linear relationship with time, number-average molecular weight (Mn) increased with monomer conversion linearly. Polydispersity index of the copolymer remained low (PDI<1.2). According to the composition of the copolymer obtained by elemental analyses, reactivity ratios of two monomers (rst=0.488, rDMF=0.303) were calculated by the Kelen-T dos equation.Reversible Addition Fragmentation Transfer polymerization of St and DMF using AIBN as initiator, three dithioesters (CPDB, CPDN, CPDPA) as chain transfer reagents was carried out successfully. The results showed that In ([M]0/[M]) had a good linear relationship with time, number-average molecular weight (Mn) increased with monomer conversion linearly at low conversion (<50%). Polydispersity index of the copolymer remained low (PDK1.3). According to the composition of the copolymer obtained by elemental analyses, reactivity ratios of two monomers (rst=0.549, rDMF=0.094) were calculated by the Kelen-Tiidos equation.
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