Method for producing a hydrophobic heat-insulating molded body

Patent metadata

Field	Value
Publication number	US-10618849-B2
Application number	US-201515501370-A
Country	US
Kind code	B2
Filing date	Jul 27, 2015
Priority date	Aug 8, 2014
Publication date	Apr 14, 2020
Grant date	Apr 14, 2020

Abstract

Process for the production of a hydrophobic thermal-insulation moulding, where a hydrophilic thermal-insulation moulding is brought into contact with a hydrophobizing agent in vapour form with formation of a thermal-insulation moulding coated with hydrophobizing agent, and this is then subjected to a press process and during the press process and/or after the press process is reacted with the hydrophobizing agent with formation of the hydrophobic thermal-insulation moulding, where
a) the density of the hydrophobic thermal-insulation moulding after the press process and after the reaction with the hydrophobizing agent is from 100 to 250 kg/m 3 , and b) the density of the hydrophilic thermal-insulation moulding on contact with the hydrophobizing agent is from 50% to less than 100% of the density of the hydrophobic thermal-insulation moulding.

First claim

The invention claimed is:

1. A process for producing a hydrophobic thermal-insulation molding, comprising:
contacting a hydrophilic thermal-insulation molding
with a hydrophobizing agent in the form of vapor, thereby forming a thermal-insulation molding coated with the hydrophobizing agent;
pressing the thermal-insulation molding coated with the hydrophobizing agent; and
during and/or after the pressing, heating the thermal-insulation molding coated with the hydrophobizing agent, thereby forming the hydrophobic thermal-insulation moulding molding,
wherein
the hydrophilic thermal-insulation molding comprises a thermal-insulation mixture comprising a fine-particle silica, IR opacifier and fiber material,
the contacting, the pressing, and the heating take place between two gas-permeable moving belts of a press,
a density of the hydrophobic thermal-insulation molding the heating is from 100 to 250 kg/m 3 , and
a density of the hydrophilic thermal-insulation molding contacted with the hydrophobizing agent is from 50% to less than 100% of the density of the hydrophobic thermal-insulation molding.

2. The process according to claim 1 , wherein in the contacting, a contact temperature T contact is from −30° C. to 150° C.

3. The process according to claim 1 , wherein in the heating, a reaction temperature T reaction is from 50° C. to 500° C.

4. The process according to claim 1 , wherein a contact time during the contacting and a heating time during the heating are in each case from 1 minute to 1 hour.

5. The process according to claim 1 , wherein the contacting and the heating take place in a chamber, and
wherein the hydrophobizing agent is introduced into the chamber until a pressure difference Δp is ≥20 mbar, wherein Δp=p 2 −p 1 , and p 1 =pressure in the chamber before the introduction of the hydrophobizing agent, and p 2 =pressure in the chamber at which the introduction of the hydrophobizing agent is stopped.

6. The process according to claim 1 , wherein the fine-particle silica is a fumed silica.

7. The process according to claim 1 , wherein a proportion of the fine-particle silica, based on the thermal-insulation mixture, is from 70 to 95% by weight.

8. The process according to claim 1 , wherein a proportion of the IR opacifier, based on the thermal-insulation mixture, is from 2 to 20% by weight.

9. The process according to claim 1 , wherein a proportion of the fiber material, based on the thermal-insulation mixture, is from 3 to 10% by weight.

10. The process according to claim 1 , wherein the hydrophobizing agent is at least one organosilicon compound selected from the group consisting of R n —Si—X 4-n and R 3 Si—Y—SiR 3 , wherein n=from 1 to 3; R═—CH 3 or —C 2 H 5 ; X═—Cl, —Br, —OCH 3 , —OC 2 H 5 , or —OC 3 H 8 ; and Y═NH or O.

11. The process according to claim 1 , wherein a proportion of the hydrophobizing agent, based on the hydrophilic thermal-insulation molding, is from 0.5 to 10% by weight.

12. The process according to claim 1 , which is carried out continuously.

13. The process according to claim 2 , wherein in the heating, a reaction temperature T reaction is from 50° C. to 500° C.

14. The process according to claim 2 , wherein a contact time during the contacting and a heating time during the heating are in each case from 1 minute to 1 hour.

15. The process according to claim 3 , wherein a contact time during the contacting and a heating time during the heating are in each case from 1 minute to 1 hour.

16. The process according to claim 2 , wherein the contacting and the heating takes place in a chamber, and
wherein the hydrophobizing agent is introduced into the chamber until a pressure difference Δp is ≥20 mbar, wherein Δp=p 2 −p 1 , and p 1 =pressure in the chamber before the introduction of the hydrophobizing agent, p 2 =pressure in the chamber at which the introduction of the hydrophobizing agent is stopped.

17. The process according to claim 3 , wherein the contacting and the heating takes place in a chamber, and
wherein the hydrophobizing agent is introduced into the chamber until a pressure difference Δp is ≥20 mbar, wherein Δp=p 2 −p 1 , and p 1 =pressure in the chamber before the introduction of the hydrophobizing agent, p 2 =pressure in the chamber at which the introduction of the hydrophobizing agent is stopped.

18. The process according to claim 13 , wherein the contacting and the heating takes place in a chamber, and
wherein the hydrophobizing agent is introduced into the chamber until a pressure difference Δp is ≥20 mbar, wherein Δp=p 2 −p 1 , and p 1 =pressure in the chamber before the introduction of the hydrophobizing agent, p 2 =pressure in the chamber at which the introduction of the hydrophobizing agent is stopped.

19. The process according to claim 2 , wherein the fine-particle silica is a fumed silica.

20. The process according to claim 3 , wherein the fine-particle silica is a fumed silica.

Assignees

• Evonik Operations Gmbh

Inventors

• Albinus Uwe
• DAENNER Johannes
• Dannehl Manfred
• Schindler Matthias
• Gaertner Gabriele

Classifications

• C04B2111/28

  Fire resistance, i.e. materials resistant to accidental fires or high temperatures · CPC title

• C04B35/64

  Burning or sintering processes (C04B33/32 takes precedence {; powder metallurgy B22F}) · CPC title

• B28B3/123

  on material in moulds or on moulding surfaces moving continuously underneath or between the rollers, e.g. on an endless belt · CPC title

• C04B32/00

  Artificial stone not provided for in other groups of this subclass · CPC title

• C04B35/82 Primary

  Asbestos; Glass; Fused silica · CPC title