Method for controlling color formation during polytetramethylene ether glycol production

US5596074A · kind A · utility

Assignee

• E.I. DU PONT DE NEMOURS AND COMPANY · US

Inventors

• Peter A. Bloxham · Houston, US
• Anne Irisa Breikss · Hockessin, US
• Richard E. Ernst · Kennett Square, US
• Leon S. Scott · Wilmington, US
• John D. Super · Wilmington, US
• James D. Verbsky · Seabrook, US

Key dates

• Filing date: Dec 22, 1995
• Grant date: Jan 21, 1997
• Expiry date: Dec 22, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C29/80
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for removing precursors, such as low boiling alkyl glycols (e.g., ethylene glycol and/or 1,2-propylene glycol), to undersirable color forming acetal impurities (e.g., 1,3 -dioxolane and 4-methyl-1,3-dioxolane) from technical grade 1,4-butanediol/2-methyl-1,4-butanediol mixtures and the like by distillative topping of the diol mixture prior to ring closing cyclization to corresponding tetrahydrofuran/3-methyl tetrahydrofuran mixture and subsequent polymerization to polytetramethylene glycol ether polymers. Such a process is useful to produce THF and PTMEG having a APHA color index of nearly zero.