Preparation of antiplasticizers for thermoplastic polyesters

US8344172B2 · kind B2 · utility

Assignee

• STEPAN COMPANY · US

Inventors

• Rick Tabor · Plymouth, US
• Brian K. Mirous · Evanston, US
• Timothy L. Lambert · Lindenhurst, US
• Michael E. O'Brien · Eugene, US
• Matthew I. Levinson · Chicago, US
• Daniel J. Dershowitz · Buffalo Grove, US

Key dates

• Filing date: Mar 25, 2011
• Grant date: Jan 1, 2013
• Expiry date: Mar 25, 2031

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/582
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for making bis(aryloxyalkyl)terephthalates useful as antiplasticizers for thermoplastic polyesters is disclosed. Dimethyl terephthalate is reacted with an excess of an aryloxyalkanol in the presence of a condensation catalyst to produce an intermediate mixture comprising a bis(aryloxyalkyl)terephthalate, a mono(aryloxyalkyl)terephthalate, and unreacted aryloxyalkanol. This mixture continues to react at reduced pressure while unreacted aryloxyalkanol is removed and the mono-ester content is reduced to less than 1 mole % based on the combined amounts of mono- and bis-esters. Both steps are performed substantially in the absence of oxygen. Additional unreacted aryloxyalkanol is then removed to provide a purified bis(aryloxyalkyl)terephthalate having an overall purity of at least 98 mole % and a yellowness index less than 10. Careful control over catalysis, exposure to air, and other process conditions enables the preparation of high yields of bis(aryloxyalkyl)terephthalates that have low color and other valuable attributes. A method of producing bis(aryloxyalkyl)terephthalate articles having improved compressive strength is also disclosed.