Synthesis of a photocrosslinkable hyperbranched polyester containing methacryloyl groups by the reaction of 1,4-bis(chloromethyl)benzene with 1,3,5-benzenetricarboxylic acid followed by reaction with methacrylic acid

The synthesis and photo-polymerization of hyperbranched polyesters (HBPEs) containing terminal methacryloyl groups (HBPE-MA) were examined. Polycondensations of 1,4-bis(chloromethyl) benzene with 1,3,5-benzenetricarboxylic acid using 1, 8-diazabicyclo[5.4.0] undec-7-ene as a base were performed to give the soluble HBPEs in satisfactorily high yields. Furthermore, HBPE-MA was synthesized by the reaction of HBPE with methacrylic acid. The photo-induced radical polymerization of HBPE-MA was performed in the presence of 2-methyl-1-[4-(methylthio) phenyl]-2-morpholinopropan-2-one (Irgacure 907), which acts as a photoinitiator in the solid film state and yields an insoluble cured film upon ultraviolet irradiation. Polymer Journal (2010) 42, 790-794; doi:10.1038/pj.2010.74