Processing Base-Catalysed Alkoxylation Products
A method of processing of base-catalysed alkoxylation products using sulphonic acid-containing ion exchangers is described, comprising providing a mixture comprising the alkali-catalysed alkoxylation product to be processed, alcohol having 1 to 4 carbon atoms and water, treating this mixture with a sulphonic acid-containing cation exchanger at >40° C. and removal of the alkoxylation product from the mixture thus treated.
1 . A method of processing of alkali-catalyzed alkoxylation products using sulphonic acid-containing ion exchangers, comprising the steps of
a) providing a mixture comprising the alkali-catalyzed alkoxylation product to be processed, alcohol having 1 to 4 carbon atoms and water,
b) treating the mixture obtained from step a) with a sulphonic acid-containing cation exchanger at >40° C.,
c) removal of the alkoxylation product from the mixture obtained in step b).
2 . The method according to claim 1 for removing alkali metal residues and odor-forming additions from the alkali-catalyzed alkoxylation products.
3 . The method according to claim 1 , wherein the alkali-catalyzed alkoxylation products to be processed originate from an alkali-metal-hydroxide- or alkali-metal-alkoxide-catalyzed alkoxylation process, have a molar mass Mw of 150 g/mol to 15 000 g/mol and a polydispersity Mw/Mn of 1.04 to 1.5.
4 . The method according to claim 1 , wherein the alkali-catalyzed alkoxylation products to be processed have 1 to 6 OH groups.
5 . The method according to claim 1 , wherein the ion exchanger used contains sulphonic acid groups, has an average particle size of 500-900 μm and has an ion exchange capacity of not less than 1.5 equ./litre (H + Form).
6 . The method according to claim 1 , wherein in step b) the mixture for treatment with the ion exchanger is composed to an extent of 35 to 95 wt %, of alkoxylation product, to an extent of 4 to 64 wt %, of alcohol having 1 to 4 carbon atoms and to an extent of 1 to 15 wt % of water.
7 . The method according to claim 1 , wherein the alkali-catalyzed alkoxylation products to be processed are adducts of alkylene oxides selected from the group consisting of ethylene oxide, propylene oxide, 1-butylene oxide, 2-butylene oxide, isobutylene oxide and styrene oxide.
8 . The method according to claim 1 , wherein in step b) the mixture from step a) is passed through an ion exchanger bed at 45° C. to 100° C.
9 . The method according to claim 1 , wherein the processing of the alkali-catalyzed alkoxylation product effects a reduction in the content of propenyl groups that is more than 40%, lower compared to the alkoxylation product used for processing.
10 . An alkoxylation product obtainable according to claim 1 .
11 . The alkoxylation product according to claim 10 , wherein the acid number is between 0 and 0.5 mg KOH/g.
12 . The alkoxylation product according to claim 10 , wherein said product is phosphate-free and the content of sodium and potassium is less than 10 ppm.
13 . (canceled)
14 . A PUR foam obtainable by reaction of at least one polyol component and at least one isocyanate component in the presence of a polyether siloxane obtained using processed alkoxylation product according to claim 1 .
15 . The method according to claim 1 , wherein the alkali-catalyzed alkoxylation products to be processed have 1 to 2 OH groups.
16 . The method according to claim 1 , wherein in step b) the mixture for treatment with the ion exchanger is composed to an extent of 45 to 85 wt % of alkoxylation product, to an extent of 12 to 53 wt % of alcohol having 1 to 4 carbon atoms, and to an extent of 2 to 10 wt % of water.
17 . The method according to claim 1 , wherein in step b) the mixture for treatment with the ion exchanger is composed to an extent of 50 to 80 wt % of alkoxylation product, to an extent of 17 to 48 wt % of alcohol having 1 to 4 carbon atoms, and to an extent of 3 to 8 wt % of water.
18 . The alkoxylation product according to claim 10 , wherein the acid number is not more than 0.3 mg KOH/g.
19 . The alkoxylation product according to claim 10 , wherein said product is phosphate-free and the content of sodium and potassium is less than 5 ppm.
20 . The method according to claim 1 , wherein the processing of the alkali-catalyzed alkoxylation product effects a reduction in a content of propenyl groups that is from 50% to 95%, lower compared to the alkoxylation product used for processing.
21 . The method according to claim 1 , wherein the alkali-catalyzed alkoxylation products to be processed are adducts of alkylene oxides, selected from the group consisting of ethylene oxide and propylene oxide.