Method for producing a prefabricated building material

Patent metadata

Field	Value
Publication number	US-2017240467-A1
Application number	US-201515519891-A
Country	US
Kind code	A1
Filing date	Oct 23, 2015
Priority date	Oct 23, 2014
Publication date	Aug 24, 2017
Grant date	—

Abstract

The present invention relates to a method for producing a gypsum-containing foamed prefabricated building material and to a gypsum-containing foamed prefabricated building material.

First claim

1 . An aqueous alkyl ketene dimer dispersion comprising
(a) an alkyl ketene dimer of the formula (I)

and/or of the formula (II)

in which
R 1 and R 2 are identical or different hydrocarbon radicals comprising 10 to 24 carbon atoms;
(b) at least one emulsifier having a nitrogen content in the range from 0.05 to 1% by weight and a Brookfield viscosity (20° C.; spindle 61 or 62; 12 rpm) in the range from about 10 to about 500 mPas in a 10% w/w aqueous solution, the emulsifier being selected from the group consisting of a starch, cellulose, starch derivative or cellulose derivative;
(c) a condensation product of phenol sulfonic acid and formaldehyde, naphthalene sulfonic acid and formaldehyde or naphthalene sulfonic acid, phenol, formaldehyde and urea wherein the sulfonic acid groups may optionally be present in protonated or deprotonated or partly in protonated and partly in deprotonated form;
wherein the dispersion has a charge density in the range from −5 to −150 μeq/g.

2 . The dispersion of claim 1 having a charge density in the range from −10 to −120 μeq/g.

3 . The dispersion of claim 1 , wherein the at least one emulsifier has a nitrogen content in the range from 0.2 to 0.8% by weight.

4 . The dispersion of claim 1 , which additionally comprises at least one fatty alcohol alkoxylate, fatty amine alkoxylate or fatty acid alkoxylate.

5 . The dispersion of claim 4 , wherein the fatty alcohol alkoxylate is a C 8 -C 18 alkanol ethoxylate with 10 to 30 ethylene oxide groups.

6 . The dispersion of claim 1 , which additionally comprises a wax.

7 . The dispersion of claim 1 , in the form of a gypsum composition which dispersion additionally comprises gypsum hemihydrate or anhydrite or a mixture thereof.

8 . The dispersion of claim 7 , wherein the gypsum hemihydrate or anhydrite is selected from α-hemihydrate, α/β-hemihydrate, β-hemihydrate, natural anhydrite, synthetic anhydrite, anhydrite obtained from flue gas desulfurization, and/or mixtures of two or more thereof.

9 . The dispersion of claim 1 , which additionally comprises an aqueous foam.

10 . The dispersion of claim 9 , wherein a foam having a density from about 50 to 300 g/l is used.

11 . The dispersion of claim 10 , wherein the foam is obtained from 0.01 to 2 g surfactant per kg gypsum hemihydrate or anhydrite.

12 . A method for producing a gypsum-containing foamed prefabricated building material comprising the steps of
(a) providing the dispersion additionally comprising a gypsum composition as defined in claim 9 ; and (b) forming, optionally curing and drying the gypsum composition to obtain the foamed prefabricated building material.

13 . The method of claim 12 , wherein the gypsum composition is obtained by adding the alkylketene dimer of the formula (I) or (II) to components (b) and (c) of the dispersion and then adding the foam.

14 . The method of claim 13 , wherein the alkyl ketene dimer is employed in the form of an aqueous dispersion.

15 . The method of claim 14 , wherein the aqueous alkyl ketene dispersion comprises 1 to 60 wt % of ketene dimer, based on the total weight of the dispersion.

16 . The method of claim 12 to 15, wherein 0.02 to 8.0 wt % of the alkyl ketene dimer, based on the mass of the gypsum hemihydrate or anhydrite, is used.

17 . A prefabricated construction chemical building material, optionally a gypsum-containing foamed prefabricated building material, comprising a gypsum body hydrophobized with the dispersion of claim 7 .

18 . A gypsum-containing prefabricated building material obtained from the dispersion according to claim 7 .

19 . The building material of claim 17 wherein the gypsum body has a core density of 0.4 to 1.1 kg/dm 3 .

20 . The building material of claim 17 selected from gypsum plasterboard panels, gypsum fiberboard panels, gypsum-containing wallboarding panels, and gypsum-containing moldings.

Assignees

• Basf Se

Inventors

• Gehrig Uwe
• Jahns Ekkehard
• Schinabeck Michael
• Pichler Martin
• Pekmezci Mehmet Akif
• Ergin Mehmet

Classifications

• C04B24/226

  Sulfonated naphtalene-formaldehyde condensation products · CPC title

• C04B24/008 Primary

  Aldehydes, ketones · CPC title

• C04B24/383

  Cellulose or derivatives thereof · CPC title

• C04B24/08

  Fats; Fatty oils; Ester type waxes; Higher fatty acids, i.e. having at least seven carbon atoms in an unbroken chain bound to a carboxyl group; Oxidised oils or fats · CPC title

• C04B28/147

  beta-hemihydrate · CPC title