RU2022113622A - DOUBLE SALT AS A POWERFUL PRIMARY TENSIDE FOR CALCIUM SULFATE MIXTURES CONTAINING PROCESSED GYPSUM - Google Patents

Claims (23)

1. A method for producing a gypsum board, which includes the following steps: a) creating a foam from a blowing agent that contains at least one double salt of an alpha-sulfonic fatty acid, b) preparation of a composition containing water and gypsum, and, if necessary, containing auxiliary agents, c) the effect of shear forces on the composition obtained in step b) with the addition of foam from step a), and d) thermal drying of the resulting composition; wherein the gypsum has a recycled gypsum content of at least 0.5% by weight, based on the total gypsum content of the composition. 2. The method according to claim 1, characterized in that the gypsum board is selected from the group consisting of gypsum boards, gypsum fiber boards, gypsum-containing wall panels and fleece-coated gypsum boards. 3. The method according to claim 1, characterized in that at least one alpha-sulfonic fatty acid double salt is a compound of formula (I):

in which R ¹ represents a linear or branched alkyl or alkylene residue with 6-16 C atoms, and M ¹ and M ² are independently selected from the group consisting of H, Li, Na, K, Ca / 2, Mg/2, ammonium and alkanolamine. 4. The method according to p. 3, characterized in that R ¹ is a saturated, linear alkyl residue with 8-16 carbon atoms. 5. The method according to p. 3, characterized in that M ¹ and M ² are Na. 6. The method of claim. 1, characterized in that thermal drying includes exposing the resulting composition to a temperature of approximately 150°C for approximately one hour. 7. Method according to claim 1, characterized in that the proportion of recycled gypsum is recycled gypsum containing siloxane. 8. Gypsum board obtained by thermal drying of an aqueous gypsum composition containing: i) at least 40.0% by weight of gypsum, and ii) at least 0.002% by weight of a blowing agent which contains at least one alpha-sulfonic fatty acid double salt, in terms of the total weight of the aqueous gypsum composition, and wherein the gypsum has a recycled gypsum content of at least 0.5% by weight, based on the total gypsum content of the gypsum composition. 9. Gypsum board according to claim 8, characterized in that at least one alpha-sulfonic fatty acid double salt is a compound of formula (I):

in which R ¹ represents a linear or branched alkyl or alkylene residue with 6-16 C atoms, and M ¹ and M ² are independently selected from the group consisting of H, Li, Na, K, Ca / 2, Mg/2, ammonium and alkanolamine. 10. Gypsum board according to claim 8, characterized in that the proportion of recycled gypsum is recycled gypsum containing siloxane.