A synthetic approach for water soluble hyperbranched poly(N,N-ethylidenebis(N-2-chloroacetyl acrylamide)) with high degree of branching via atom transfer radical polymerization/self-condensing vinyl polymerization

A novel acrylamide A₂B₂* (A = alkene, B* = alkyl chlorine) type inimer was obtained from commercially available 1,2-ethylenediamine, chloroacetyl chloride and acryloyl chloride. The as-prepared monomer can form water-soluble hyperbranched poly(N,N-ethylidene bis(N-2-chloroacetyl acrylamide))s (HPECA) through atom transfer radical polymerization/self-condensing vinyl polymerization method in the presence alkyl chlorine/CuCl/2,2-bipyridine activation system which can effectively suppress the gelation formation. ¹H-NMR spectra and dual detector size exclusion chromatography proved the hyperbranched structure indisputably, and the degree of branching was determined by the detailed analyses of ¹H-NMR spectra. The trend of the degree of branching was in consistent with the result of Mark-Houwink exponent a. The experiment results suggested that the conversion was 67%, M _w = 13.2 × 10⁴, Mark-Houwink a = 0.282 and the degree of branching = 64% when the reaction temperature was 120 °C, reaction time = 168 h and N,Nethylidene bis(N-2-chloroacetyl acrylamide):Cu(I) = 50:0.62.