Process and apparatus for crystallization of polytrimethylene terephthalate (PTT)

US6740733B2 · kind B2 · utility

Assignee

• SHELL OIL COMPNY · US

Inventors

• James Gao Lee · Houston, US
• Thomas Louis De Lellis · Katy, US
• Edward James Denton · Richmond, US
• Kevin Allen · Katy, US
• Stefan Deiss · Harxheim, DE
• Klaus Mackensen · Frankfurt am Main, DE

Key dates

• Filing date: Nov 25, 2002
• Grant date: May 25, 2004
• Expiry date: Nov 25, 2022

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G63/183
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Disclosed is a process for reducing the self-adhesiveness of polytrimethylene terephthalate pellets, which can be carried out in a continuous or batch manner comprising the steps of:a) introducing polytrimethylene terephthalate pellets having an intrinsic viscosity of at least about 0.4 dl/g into a conduit containing a liquid which is moving through the conduit, thereby causing the pellets to move through the conduit with the liquid;b) adjusting the temperature of the pellets and the liquid to a temperature of about 50 to about 95° C. for a time sufficient to induce a degree of crystallinity of at least about 35% in the pellets; andc) separating the pellets from the liquid.