Manufacturing polyesters

A continuous process of manufacturing polyester comprising the steps of:

• a. introducing a polyol and a polycarboxylic acid or an anhydride of a polycarboxylic acid into a pre-reactor and allowing the polyol and the polycarboxylic acid or the anhydride of the polycarboxylic acid to react to obtain a pre-polymer mixture including a polyfunctional ester;
• and
• b. introducing the pre-polymer mixture into an inlet section of a distillation column having a stripping section below the inlet section and a rectifying section above the inlet section;
• c. supplying a stripping gas into the bottom of the distillation column;
• d. allowing the polyfunctional ester to polymerize in the stripping section so as to form a polyester and a gaseous mixture including water and unreacted reactants;
• e. removing the polyester from the bottom of the distillation column;
• and
• f. allowing the gaseous mixture to pass through the rectifying section, removing from the top of the distillation column a gaseous phase, at least partially condensing the gaseous phase and returning at least part of the condensed gaseous phase as reflux into the top of the distillation column.