Patent ID: 6124423
Filing Date: 2000-09-26
Classification: C08G

Abstract:
A process for crystallizing polyethylene naphthalate copolyester comprising:a) copolymerizing at least 60 mole % of 2,6-naphthalene dicarboxylic acid, based on the total moles of carboxylic acids; with at least 80 mole % of ethylene glycol and from 2 mole % to 20 mole % of a polyol having three or more carbon atoms, each based on the total moles of polyols, to form PEN copolymer solids; andb) subsequently crystallizing said solids comprising heating said solids to at least their sticking temperature at an average rate of at least 10.degree. C./min, to form agglomerate-free crystallized solids.