Aliphatic hyperbranched pely(ester-amine)s with terminal acrylate groups were synthesized by Michael addition reaction between pizine and trimethylol- propanetriacrylate (TMPTA) under various molar ratios
and their structures were characterized by 1H-NMR.GPC and DSC analysis.The multi-peaks within δ 4.04~4.18 (RCH2OCOR’)in the 1H-NMR spectra were analyzed andthe peaks at δ4.15
δ4.06~4.07 and δ 4.04 can be assigned to terminal(T)
linear(L) and dendritic units(D)
respectively.Based on 1H-NMR spectra
the degree of branching (DB) for these polymers were calculated by using both the Frechet method and the Frey method.With the molar ratio between pizine and TMPTA increased to 1/1
the terminate units decreased
both of the dendritic and linear units increased
while Mn and Mw/Mn became large and the Tg value became hish
accordingly.Moreover
cured films were obtained throuIsh UV radiation of the polymers.The gel contents for the films decreased with increasing the molar ratio between pizine and TMPTA
which may account for the changes of their mechanical properties.