A hyperbranched macromolecule of polyester type comprising a central monomeric or polymeric nucleus and at least one generation of a branching chain extender having at least three reactive sites of which at least one is a hydroxyl or hydroxyalkyl substituted hydroxyl group and at least one is a carboxyl or terminal epoxide group. The nucleus is an epoxide compound having at least one reactive epoxide group. Optionally, the macromolecule comprises at least one generation consisting of at least one spacing chain extender having two reactive sites of which one is a hydroxyl or hydroxyalkyl substituted hydroxyl group and one is a carboxyl or terminal epoxide group. The macromolecule may be terminated by means of at least one chain stopper.