A series of aromatic hyperbranched polyesters with phenol and acetate terminal/side groups respectively has been synthesized. Both a direct polycondensation of 4',4”-dihydroxy-2-carboxyltriphenylmethane (phenolphthalin) and an ester-exchange reaction of 4', 4"-diacetoxy-2- carboxyltriphenylmethane successfully result in hyperbranched polyesters. The weight-average molecular weight measured by GPC with PS standard ranges from 20000 to 80000. ~(13)C NMR studies show that the degree of branching is a little higher than 50%. The glass transition temperature of the resulting polyester depends on the type of terminal and side groups. With functional groups in their terminals, the hyperbranched polyesters obtained show high thermostability similar to the linear polymers. In contrast, due to the macromolecular architecture and presence of functional groups, hyperbranched polyesters with acetoxy terminals exhibit excellent solubility, differing from ordinary linear polymers. The solubility of hyperbranched polyesters with phenol terminals is poor owing to the presence of hydrogen bonds. After acidification of the polymer the physical network resulting from hydrogen bonds was destroyed, and then the polymer could be dissolved in conventional organic solvents.

Key words: FORMIC ACID P, TRIPHENYLMETHANE P, BRANCHED POLYMER, POLYESTER