Abstract: The present invention relates to a process for preparing a polyester resin having a gel content of less than 0.45 wt %, based on the total weight of the polyester resin, and a glass transition temperature of between 40 and 70° C., comprising the step of reacting a polyester resin precursor with a chain extender which is different from the building blocks of the polyester precursor resin, optionally in the presence of a catalyst, at a temperature between 170 and 300° C. in a continuous reactor, wherein the polyester resin precursor comprises a functional group present as end group selected from hydroxyl or carboxyl, and optionally a functional group in the polyester resin precursor backbone selected from hydroxyl, carboxyl, amine, and carbonate, and the molar ratio of the functional group in the polyester resin precursor backbone to the functional group present as end group is at most 10:1. The invention further pertains to a polyester resin having a gel content of less than 0.

Abstract: The invention relates to a process wherein one or more polyamines, each with one or more —NH2 functions and one or more second amine functions, said second amine functions having a lower lactone reactivity than said —NH2 functions, is reacted in a first step with one or more lactones, hydroxyacids, cyclic carbonates, or mixtures thereof, to form a polyamine-derived compound with amide and/or urethane groups, which polyamine-derived compound is reacted in a second step with one or more at least bifunctional amine-specific reagents to form an intermediate optionally comprising ester and/or carbonate groups, wherein in the second step optionally an additional amine modifier is co-reacted and in the intermediate at least two polyamine residues, or if a modifier is co-reacted, at least one polyamine residue and at least one optional amine modifier residue, are linked by said bifunctional amine-specific reagent.