Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – From heterocyclic reactant containing as ring atoms oxygen,...
Reexamination Certificate
2001-10-29
2003-03-04
Wood, Elizabeth D. (Department: 1755)
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
From heterocyclic reactant containing as ring atoms oxygen,...
C528S403000, C528S408000, C528S409000, C528S410000, C528S414000, C528S415000, C528S417000, C526S243000, C526S243000, C526S243000, C502S175000, C502S200000
Reexamination Certificate
active
06528616
ABSTRACT:
The present invention relates to new double metal cyanide (DMC) catalysts for the production of polyether polyols by polyaddition of alkylene oxides to starter compounds containing active hydrogen atoms.
Double metal cyanide (DMC) catalysts for the polyaddition of alkylene oxides to starter compounds containing active hydrogen atoms are known (see for example U.S. Pat. Nos. 3,404,109, 3,829,505, 3,941,849 and 5,158,922). The use of these DMC catalysts for the production of polyether polyols lead in particular to a reduction of the proportion of monofunctional polyethers with terminal double bonds, so-called monools, compared to the conventional production of polyether polyols by means of alkali metal catalysts such as alkali metal hydroxides. The polyether polyols that are thus obtained may be processed into high-grade polyurethanes (for example elastomers, foams, coatings). DMC catalysts are normally obtained by reacting an aqueous solution of a metal salt with an aqueous solution of a metal cyanide salt in the presence of an organic complex ligand, e.g. an ether. In a typical catalyst preparation aqueous solutions of zinc chloride (in excess) and potassium hexacyanocobaltate for example are mixed and then dimethoxyethane (glyme) is added to the resultant suspension. After filtration and washing the catalyst with aqueous glyme solution, an active catalyst of the general formula
Zn
3
[Co(CN)
6
]
2
x
ZnCl
2
y
H
2
O
z
glyme
is obtained (see e.g. EP-A 700 949).
From JP-A 4 145 123, U.S. Pat. No. 5,470,813, EP-A 700 949, EP-A 743 093, EP-A 761 708 and WO 97/40086 DMC catalysts are known, which by using tert.-butanol as organic complex ligand (alone or in combination with a polyether (EP-A 700 949, EP-A 761 708, WO 97/40086)) further reduce the proportion of monofunctional polyethers with terminal double bonds in the production of polyether polyols.
Furthermore, the induction time in the polyaddition reaction of alkylene oxides with corresponding starter compounds is reduced and the catalyst activity is raised by the use of these DMC catalysts.
The object of the present invention was to provide further improved DMC catalysts for the polyaddition of alkylene oxides to corresponding starter compounds that have an increased catalyst activity compared to the hitherto known types of catalyst. Due to the reduction of the alkoxylation times this leads to an improved economy of the production process for polyether polyols. Ideally, due to its increased activity the catalyst can then be used in such low concentrations (25 ppm or less) that the very complicated and costly separation of the catalyst from the product is no longer necessary and the product can be used directly for producing polyurethanes.
It has now surprisingly been found that DMC catalysts that contain an &agr;,&bgr;-unsaturated carboxylic acid ester as complex ligand have a greatly increased activity in the production of polyether polyols.
The present invention accordingly provides a double metal cyanide (DMC) catalyst containing
a) one or more, preferably one double metal cyanide compound,
b) one or more, preferably one organic complex ligand different from c), and
c) one or more, preferably one &agr;,&bgr;-unsaturated carboxylic acid ester.
The catalyst according to the invention may optionally contain d) water, preferably in an amount of 1 to 10 wt. %, and/or e) one or more water-soluble metal salts, preferably in an amount of 5 to 25 wt. %, of the formula (I) M(X)
n
from the production of the double metal cyanide compounds a). In formula (I) M is selected from the metals Zn(II), Fe(II), Ni(II), Mn(II), Co(II), Sn(II), Pb(II), Fe(III), Mo(IV), Mo(VI), Al(III), V(V), V(IV), Sr(II), W(IV), W(VI), Cu(II), and Cr(III).
Particularly preferred are Zn(II), Fe(II), Co(II) and Ni(II). X, which are identical or different, preferably identical, denote an anion preferably selected from the group comprising halides, hydroxides, sulfates, carbonates, cyanates, thiocyanates, isocyanates, isothiocyanates, carboxylates, oxalates or nitrates. The value of n is 1, 2 or 3.
The double metal cyanide compounds a) contained in the catalysts according to the invention are the reaction products of water-soluble metal salts and water-soluble metal cyanide salts.
Water-soluble metal salts suitable for the production of double metal cyanide compounds a) preferably have the general formula (I) M(X)
n
, wherein M is selected from the metals Zn(II), Fe(II), Ni(II), Mn(II), Co(II), Sn(II), Pb(II), Fe(III), Mo(IV), Mo(VI), Al(III), V(V), V(IV), Sr(II), W(IV), W(VI), Cu(II), and Cr(III). Particularly preferred are Zn(II), Fe(II), Co(II) and Ni(II). The anions X are identical or different, preferably identical, and are preferably selected from the group comprising halides, hydroxides, sulfates, carbonates, cyanates, thiocyanates, isocyanates, isothiocyanates, carboxylates, oxalates or nitrates. The value of n is 1, 2 or 3.
Examples of suitable water-soluble soluble metal salts are zinc chloride, zinc bromide, zinc acetate, zinc actetylacetonate, zinc benzoate, zinc nitrate, iron(II) sulfate, iron(II)bromide, iron(II)chloride, cobalt(II)chloride, cobalt(II)thiocyanate, nickel(II)chloride and nickel(II)nitrate. Mixtures of various water-soluble soluble metal salts may also be used.
Water-soluble soluble metal cyanide salts suitable for the production of double metal cyanide compounds a) preferably have the general formula (II) (Y)
a
M′(CN)
b
(A)
c
, wherein M′ is selected from the metals Fe(II), Fe(III), Co(III), Co(II), Cr(II), Cr(III), Mn(II), Mn(III), Ir(II), Ni(II), Rh(III), Ru(II), V(IV) and V(V). Particularly preferably M′ is selected from the metals Co(II), Co(III), Fe(II), Fe(III), Cr(III), Ir(III) and Ni(II). The water-soluble soluble metal cyanide salt may contain one or more of these metals. The cations Y are identical or different, preferably identical, and are selected from the group comprising alkali metal ions and alkaline earth metal ions. The anions A are identical or different, preferably identical, and are selected from the group comprising halides, hydroxides, sulfates, carbonates, cyanates, thiocyanates, isocyanates, isothiocyanates, carboxylates, oxalates or nitrates a as well as b and c are integers, the values for a, b and c being chosen so as to ensure the electroneutrality of the metal cyanide salt; a is preferably 1, 2, 3 or 4; b is preferably 4, 5 or 6; c preferably has the value 0. Examples of suitable water-soluble metal cyanide salts are potassium hexacyanocobaltate(III), potassium hexacyanoferrate(II), potassium hexacyanoferrate(III), calcium hexacyanocobaltate(III) and lithium hexacyanocobaltate(III).
Preferred double metal cyanide compounds a) that are contained in the catalysts according to the invention are compounds of the general formula (III)
M
x
[M′
x
,(CN)
y
]
z
,
wherein
M is defined as in formula (I) and
M′ is defined as in formula (II), and
x, x′, y and z are integers and are selected so as to ensure the electroneutrality of the double metal cyanide compound.
Preferably
x=3, x′=1, y=6 and z=2,
M=Zn (II), Fe (II), Co (H) or Ni (II) and
M′=Co (III), Fe (III), Cr (III) or Ir (III).
Examples of suitable double metal cyanide compounds a) are zinc hexacyanocobaltate(III), zinc hexacyanoiridate(III), zinc hexacyanoferrate(III) and cobalt(II)hexacyanocobaltate(III). Further examples of suitable double metal cyanide compounds may be found for example in U.S. Pat. No. 5,158,922. It is particularly preferred to use zinc hexacyanocobaltate(III).
The organic complex ligands b) contained in the DMC catalysts according to the invention are in principle known and are described in detail in the prior art (for example in U.S. Pat. Nos. 5,158,922, 3,404,109, 3,829,505, 3,941,849, EP-A 700 949, EP-A 761 708, JP-A 4 145 123, U.S. Pat. No. 5,470,813, EP-A 743 093, and WO 97/40086). Preferred organic complex ligands are water-soluble organic compounds with heteroatoms such as oxygen, nitrogen, phosphorus or sulfur, that can form
Gupta Pramod
Hofmann Jörg
Ooms Pieter
Mrozinski, Jr. John E.
Wood Elizabeth D.
LandOfFree
Double metal cyanide catalysts for the production of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Double metal cyanide catalysts for the production of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Double metal cyanide catalysts for the production of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3070573