Patent · US Expired

Preparation of polytetrahydrofuran

US5641857A · kind A · utility

9Cited by

3References

8Claims

0Family size

Assignee

BASF SE

Inventors

Roman Dostalek · Neuleiningen, DE
Rolf Fischer · Heidelberg, DE
Ulrich Mueller · Hamburg, DE
Rainer Becker · Bad Dürkheim, DE

Key dates

Filing date	Nov 7, 1995
Grant date	Jun 24, 1997
Priority date	—
Expiry date	Nov 7, 2015

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC08G65/2657
WIPO fieldMacromolecular chemistry, polymers
WIPO sectorChemistry

Abstract

Polytetrahydrofuran or polytetrahydrofuran monoesters of C.sub.1 -C.sub.20 -monocarboxylic acids or polytetrahydrofuran monoethers of monohydric C.sub.1 -C.sub.20 -alcohols, having an average molecular weight of from 250 to 10,000 Dalton and liquid at room temperature, are prepared by the cationic polymerization of tetrahydrofuran in the presence of a telogen by a process in which tetrahydrofuran is polymerized in the presence of water, 1,4-butanediol and/or polytetrahydrofuran having an average molecular weight of from 200 to 700 Dalton and/or of a C.sub.1 -C.sub.20 -monocarboxylic acid and/or of a monohydric C.sub.1 -C.sub.20 -alcohol with the aid of a catalytic amount of a zeolite catalyst which has an SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of from 4:1 to 100:1 and in which the population ratio P of the acid centers on the external surface of the zeolite to the total number of acid centers of the zeolite is 0.03/l or more.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.