Process for preparing polytetrahydrofuran and derivatives thereo

Details Process for preparing polytetrahydrofuran and derivatives thereo Process for preparing polytetrahydrofuran and derivatives thereo

1999-04-01

2000-08-29

Richter, Johann

Organic compounds -- part of the class 532-570 series

Organic compounds

Oxygen containing

568606, 560103, 560240, C07C 4310, C07C 4311, C07C 6976, C07C 6724

Patent

active

061111473

DESCRIPTION:

BRIEF SUMMARY
FIELD OF THE INVENTION

The present invention relates to an improved process for preparing polytetrahydrofuran, copolymers of tetrahydrofuran and 2-butyne-1,4-diol, diesters of these polymers with C.sub.2 -C.sub.20 -monocarboxylic acids or monoesters of these polymers with C.sub.1 -C.sub.10 -monocarboxylic acids by polymerization of tetrahydrofuran in the presence of one of the telogens water, 1,4-butanediol, 2-butyne-1,4-diol, polytetrahydrofuran having a molecular weight of from 200 to 700 Dalton, a C.sub.1 -C.sub.10 -monocarboxylic acid or an anhydride of a C.sub.2 -C.sub.20 -monocarboxylic acid or a mixture of these telogens over a heterogeneous supported catalyst which comprises a catalytically active amount of an oxygen-containing molybdenum and/or tungsten compound on an oxidic support material and which has been calcined at from 500.degree. C. to 1000.degree. C. after application of the precursor compounds of the oxygen-containing molybdenum and/or tungsten compounds onto the support material precursor.
Polytetrahydrofuran ("PTHF"), also known as poly(oxybutylene glycol), is a versatile intermediate in the plastics and synthetic fibers industries and serves, inter alia, for the preparation of polyurethane, polyester and polyamide elastomers for whose preparation it is used as diol component. In addition, polytetrahydrofuran as well as some of its derivatives is a valuable auxiliary in many applications, for example as dispersant or for deinking waste paper.
In industry, PTHF is advantageously prepared by polymerization of tetrahydrofuran over suitable catalysts in the presence of reagents whose addition makes it possible to control the length of the polymer chains and thus to set the mean molecular weight to the desired value (chain-termination reagents or "telogens"). The control is effected here by selection of type and amount of the telogen. Selection of suitable telogens makes it possible to introduce additional functional groups at one end or both ends of the polymer chain. Thus, for example, the monoesters or diesters of PTHF can be prepared by using carboxylic acids or carboxylic anhydrides as telogens. Other telogens, for example those having two hydroxy groups such as 1,4-butanediol, 2-butyne-1,4-diol or low molecular weight PTHF not only act as chain-termination reagents, but are also incorporated into the growing polymer chain of the PTHF. In this way, the PTHP can also be chemically modified. An example of this is the use of the telogen 2-butyne-1,4-diol whose addition leads to the presence of a proportion of C.tbd.C triple bonds in the polymer chains of the PTHF.
PTHF modified in this way can be further altered chemically at these points by means of the reactivity of these triple bonds, for example by hydrogenation of the triple bonds to double bonds, by subsequent grafting-on of other monomers for adjusting the properties of the polymer, crosslinking to form polymers having a comparatively rigid structure, or other conventional procedures of polymer chemistry. The complete hydrogenation of the triple bonds present is likewise possible and generally leads to PTHF having a particularly low color number.
DE-A 44 33 606 describes a process for preparing PTHF, PTHF diesters of C.sub.2 -C.sub.20 -monocarboxylic acids or PTHF monoesters of C.sub.1 -C.sub.10 -monocarboxylic acids by polymerization of tetrahydrofuran over a heterogeneous catalyst in the presence of one of the telogens water, 1,4-butanediol, PTHF having a molecular weight of from 200 to 700 Dalton, a C.sub.1 -C.sub.10 -monocarboxylic acid or an anhydride of a C.sub.2 -C.sub.20 -monocarboxylic acid or a mixture of these telogens, with the catalyst being a supported catalyst which comprises a catalytically active amount of an oxygen-containing tungsten or molybdenum compound or a mixture thereof on an oxidic support material and which has been calcined at from 500.degree. C. to 1000.degree. C. after application of the precursor compounds of the oxygen-containing molybdenum and/or tungsten compounds onto the support material precu

REFERENCES:
patent: 3893947 (1975-07-01), Young
patent: 4485005 (1984-11-01), O'Hara
patent: 5773648 (1998-06-01), Becker et al.

Affiliated with

Also associated with

Rating

Process for preparing polytetrahydrofuran and derivatives thereo does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process for preparing polytetrahydrofuran and derivatives thereo, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for preparing polytetrahydrofuran and derivatives thereo will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1251604