Process for the preparation of perfluoropolyoxyalkylenes with hydroxyl end groups

US6509509B2 · kind B2 · utility

Assignee

• Ausimont S.p.A. · IT

Inventors

• Claudio Tonelli · Vimercate, IT
• Antonio Russo · Milano, IT
• Ezio Strepparola · Bergamo, IT

Key dates

• Filing date: Dec 29, 2000
• Grant date: Jan 21, 2003
• Expiry date: Dec 29, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G65/007
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A process for preparing perfluoropolyoxyalkylenes with hydroxyl end groups having structure:T1—CFW1—O—Rf—CFW2—T2  (I)wherein: T1, T2, are selected from —CH2OH, —F, —CF3, —CF2CF3 with the proviso that at least one of T1 and T2 is —CH2OH;W1 and W2 are selected from F, CF3;Rf is a perfluoropolyoxyalkylene chain having a number average molecular weight 500-10,000 comprising one or more units of the type —CF2CF2O—, —CF2O—, —C3F6O—, —CF2(CF2)zCF2O— (z=1,2); —CR4R5CF2CF2O— with R4 and R5 selected from H, Cl, perfluoroalkyl group; said process comprising the following steps:a) adding an ester precursor having structure (I) and T1, T2 end groups selected from —F, —CF3, —CF2CF3, —COOR (R=linear or branched alkyl group having a number of C atoms from 1 to 5), with the proviso that at least one of T1 and T2 is —COOR, in a reaction mixture formed by:an inert or protic reaction solvent;a reducing agent selected from metal hydrides;an unreactive organic base with respect to the ester;b) hydrolysis of the product obtained in step a) for o…