DRY BUILDING MATERIAL MIXTURE AND THERMAL INSULATION PLASTER RESULTING THEREFROM

Abstract

The invention relates to a dry building material mixture, in particular a plastering mortar, the dry building material mixture comprising at least on aerogel.

Claims

1-12. (canceled)

13. A dry building material mixture for producing an insulation plaster, characterized in that the dry building material mixture contains (A) an aerogel in quantities from 3 to 35% by weight, in relation to the dry building material mixture, (B) at least one lightweight aggregate, in quantities from 40 to 75% by weight, in relation to the dry building material mixture, (C) at least one lime-based binding agent, in quantities from 8 to 40% by weight, in relation to the dry building material mixture, (D) at least one cement-based binding agent, in quantities from 1.5 to 10% by weight, in relation to the dry building material mixture, and (E) at least one additive in quantities from 0.1 to 5% by weight, in relation to the dry building material mixture. wherein the dry building material mixture contains the aerogel and the lightweight aggregate in a weight-based ratio of aerogel to lightweight aggregate from 1:1 to 1:13, and wherein the dry building material mixture contains the lime-based binding agent in a weight-based ratio of lime-based binding agent to cement-based binding agent from 1:1 to 15:1.

14. The dry building material mixture of claim 13, wherein the at least one lightweight aggregate is perlite.

15. The dry building material mixture of claim 13, wherein at least one lime-based binding agent is hydraulic lime.

16. The dry building material mixture of claim 13, wherein at least one cement-based binding agent is white portland cement.

17. The dry building material mixture according to claim 13, characterized in that the dry building material mixture contains the aerogel in quantities from 10 to 30% by weight, especially preferably 15 to 25% by weight, in relation to the dry building material mixture, and/or in that the aerogel contained in the dry building material mixture has a particle size from 0.01 to 10 mm, in particular 0.05 to 8 mm, preferably 0.1 to 7 mm, preferably 0.2 to 6 mm, particularly preferably 0.5 to 5 mm, especially preferably 0.5 to 4 mm, extremely preferably 0.5 to 2 mm.

18. The dry building material mixture according to claim 13 characterized in that the dry building material mixture also contains an aggregate, in particular selected from natural or artificial rocks, metals or glasses, in particular wherein the aggregate is a lightweight aggregate, in particular with a particle gross density of at most 2.0 kg/dm.sup.3 and is in particular selected from the group comprising volcanic rock, perlite, vermiculite, pumice, foam glass and expanded glass, expanded clay, expanded shale, expanded polystyrene, tuff, expanded mica, cinders, lava sand, foam plastics and mixtures thereof, preferably perlite.

19. The dry building material mixture of claim 13, including a dry building material that is an insulation plaster, in particular a thermal insulation plaster, for thermal insulation of buildings, obtainable from a dry building material mixture, wherein the insulation plaster can be obtained by making up the dry building material mixture with water in quantities of 70 to 150% by weight, in relation to the dry building material mixture, and wherein the cured insulation plaster has a compressive strength from 0.4 to 2.5 N/mm.sup.2.

20. The dry building material mixture of claim 13, including a dry building material that is an insulation plaster, characterized in that: the cured insulation plaster has a thermal conductivity in the range from 0.02 to 0.055 W/(mK), in particular 0.022 to 0.050 W/(mK), preferably 0.024 to 0.045 W/(mK), preferably 0.026 to 0.040 W/(mK), particularly preferably 0.028 to 0.032 W/(mK), and/or the cured insulation plaster has a water vapor diffusion resistance factor , determined according to DIN EN ISO 12542, in the range from 2 to 9, in particular 3 to 7, preferably 4 to 6.

21. The dry building material of claim 13 incorporated into a plastering mortor for producing an insulation plaster, for insulation of constructions.

22. The dry building material of claim 13 incorporated into a plastering mortor for producing a thermal insulation plaster, for thermal insulation of constructions.

23. A multi-layer insulation plaster system, which has at least one insulation plaster layer, consisting of an insulation plaster produced from the dry building material mixture of claim 1 and containing at least one aerogel and a surface coating, wherein the coating is arranged at least on a surface provided with the insulation plaster system, in particular a side of the insulation plaster layer facing away from a building wall, and preferably covers said layer at least substantially.

24. The multi-layer insulation plaster system according to claim 23, characterized by the following layer structure, starting from a surface provided with the insulation plaster system: a first insulation plaster layer, containing at least one aerogel, support layer, a second insulation plaster layer, primer layer and surface coating.

25. The multi-layer insulation plaster system according to claim 23, characterized in that the insulation plaster system has a layer thickness from 1.5 to 14 cm, in particular 1.5 to 10 cm, preferably 2.5 to 9 cm, more preferably 3.5 to 8 cm.

26. The multi-layer insulation plaster system of claim 24 incorporated into an insulation panel.

27. The multi-layer insulation plaster system according to claim 23, characterized in that the insulation plaster system has a layer thickness from 1.5 to 14 cm, in particular 1.5 to 10 cm, preferably 2.5 to 9 cm, more preferably 3.5 to 8 cm.

28. A composite thermal insulation system, comprising a thermal insulation panel and an insulation plaster system according to claim 23, in particular wherein on a surface to be insulated first of all the thermal insulation panel is arranged and then the insulation plaster system, in particular, wherein the composite thermal insulation system has a thickness from 4 to 12 cm, in particular 5 to 10 cm, preferably 5.5 to 9 cm, more preferably 6 to 8 cm, and/or in particular, wherein the composite thermal insulation system has a thermal conductivity in the range from 0.015 to 0.045 W/(mK), in particular 0.017 to 0.040 W/(mK), preferably 0.020 to 0.035 W/(mK), more preferably 0.022 to 0.027 W/(mK).

29. The composite thermal insulation system according to claim 28, characterized by the following layer structure: thermal insulation panel, first insulation plaster layer, containing at least one aerogel, support layer, second insulation plaster layer, primer layer and surface coating.

30. An insulation plaster panel, including the insulation plaster system of claim 23.

31. An insulation plaster panel, consisting of an insulation plaster derived from the dry building material of claim 13 containing at least one aerogel.

Description

[0154] In the drawings:

[0155] FIG. 1 shows a schematic representation of the insulation plaster layer 1 according to the invention which is applied to a building wall 2;

[0156] FIG. 2 shows a schematic representation of the insulation plaster system 3 according to the invention which is applied to a building wall 2;

[0157] FIG. 3 shows a schematic representation of a composite thermal insulation systems 8 according to the invention which is applied to a building wall 2;

[0158] FIG. 4 shows the schematic structure of a thermal insulation panel 9 which is preferably used according to the invention.

[0159] In particular FIG. 1 shows a representation of an insulation plaster layer 1 according to the invention which is applied to a wall 2 of a building to be insulated. In a departure from the drawings it may in particular be provided here that the house wall has been pretreated, in particular with a primer, before application of insulation plaster layer 1 the according to the invention.

[0160] In particular FIG. 2 shows a preferred embodiment of the insulation plaster system 3 according to the invention which is applied to a house wall 2. The insulation plaster system 3 according to the invention has in particular an insulation plaster layer 1 containing at least one aerogel as well as a surface coating 4 which is proof against driving rain and is open to diffusion. Between the surface coating 4 and the insulation plaster layer 1 is provided a primer layer 5 which ensures good adhesion between the surface coating 4 and the layers of the insulation plaster system 3 lying below it. A further insulation plaster layer 6 which contains no aerogel is arranged between the primer layer 5 and the insulation plaster layer 1, and a support layer 7, which preferably consists of a fiberglass fabric with a mesh size of 1313 mm, is located between the insulation plaster layers 1 and 6. The insulation plaster system 3 according to the invention is open to diffusion and proof against driving rain.

[0161] FIG. 3 shows in particular a schematic assertion of a preferred composite thermal insulation system 8 according to the invention, which consists of an insulation plaster system 3 and an insulation plaster panel 9 consists. The insulation plaster panel 9 is fastened by means of a 2-component adhesive 10 to the house wall 2. The insulation plaster system 3 according to the invention is applied directly to the thermal insulation panel 9 in the main insulation direction, i.e. onto the main surface or broad surface of the thermal insulation panel 9, wherein the insulation plaster layer 1 containing at least one aerogel directly adjoins the insulation plaster panel 9. The insulation plaster layer 1 is followed by a support layer 7 as well as a further insulation plaster layer 6 containing no aerogel. A primer layer 5, to which finally the surface coating 4 is applied, is applied externally to the insulation plaster layer 6. The thermal composite system according to the invention designed to be open to diffusion and proof against driving rain in the main insulation direction, i.e. perpendicular to the house wall 2.

[0162] In particular FIG. 4 shows a preferred embodiment according to the invention of the thermal insulation panel 9 which is used according to the invention. The thermal insulation panel 9 has a basic body, which is formed by the narrow sides 11 of the thermal insulation panel as well as an internal structure 12. The internal structure 12 forms hexagonal, in particular honeycomb cavities 13, which extend uniformly over the entire thickness of the thermal insulation panel 9 and contain an aerogel. The main surfaces or broad surfaces of the thermal insulation panel 9 are covered with a sheet material 14, in particular with a fiberglass fabric which has a mesh size of 22 mm, in particular the broad surfaces of the thermal insulation panel 9 are covered with a sheet material. The fiberglass fabric serves, on the one hand, as a trickle protection against inadvertent falling out of the aerogel from the interstices 12 of the thermal insulation panel 9 and, on the other hand, as an anchor or reinforcement for plaster layers, wherein the plaster does not penetrate into the interior of the panel, at least not substantially into the interior of the plate.

EXEMPLARY EMBODIMENTS

1. Method for Producing the Aerogel

[0163] The aerogel used within the context of the present invention is produced in a multi-stage process, comprising the following process steps:

[0164] 1. Production of the Hydrosol [0165] A commercial sodium silicate solution is diluted with deionized water and is then led through a highly acidic cation exchanger resin on the basis of sulfonated and divinylbenzene crosslinked polystyrene. A hydrosol in which the sodium ions of the silicate are almost completely replaced by protons is obtained as a reaction product. The completeness of the ion exchange reaction is checked by conductivity measurement.

[0166] 2. Production of a Hydrogel [0167] The hydrosol obtained in method step 1 is heated to 50 C. and admixed with N,N-dimethyl formamide with constant stirring. For acceleration of the starting condensation reaction, molar aqueous ammonia solution is added to the mixture 6 until the solution a reaches weakly acidic pH value in the range from 4.2 to 4.9. In order to form the gel the hydrosol is left to mature for several hours at constant temperature. Then by addition of deionized water, while maintaining constant temperature and stirring, the resulting hydrogel is crushed to particle sizes in the range from 0.5 to 1 cm. The mixture containing the hydrogel is cooled to 35 C. and again left to mature for several hours.

[0168] 3. Production of the Alcogel [0169] The hydrogel obtained in method step 3 is admixed with methanol until the volume ratios of water and methanol are approximately the same. Then the gel rests for several hours. Next a majority of the solvent is separated off from the reaction mixture by filtration. Then the remaining residue is again admixed with methanol. A slow solvent exchange takes place, in which water is replaced by methanol. The separation of the solvent mixture and the addition of methanol are repeated if required. An alcogel is produced which matures for several hours at constant temperature. [0170] The recovered solvent mixture is transferred to a distillation apparatus and separated by distillation.

[0171] 4. Surface Modification: [0172] The alcogel obtained in method step 3 is admixed, at constant temperature with stirring, with a solution of hexamethyl disilazane and in n-hexane, with nitric acid being used as catalyst After a reaction time of 20 hours is the surface reaction is largely completed.

[0173] 5. Solvent Exchange [0174] The reaction mixture obtained in method step 4 is separated by filtration from a majority of the solvent and the remaining residue is admixed with n-hexane. The step is repeated multiple times if required. In this way the methanol is largely replaced by n-hexane. [0175] The recovered solvent mixture is transferred to a distillation apparatus and separated by distillation.

[0176] 6. Drying [0177] The remaining solventprimarily n-hexaneis removed by distillation and the alcogel granulate still wetted with solvent residues is removed from the reaction vessel and dried in a vacuum at 50 C. for several hours while being carefully stirred and shaken. [0178] In this way a silica aerogel with the following characteriztics is obtained: [0179] particle size: 0.5 to 5 mm, [0180] density: 0.18 to 0.20 g/cm.sup.3, [0181] contact angle 110 to 150, [0182] thermal conductivity: 0.024 to 0.026 W/(mK), [0183] pore diameter: 100 to 300 nm, [0184] transparency to light: none [0185] The aerogel obtained is subdivided into the required size fractions by sieving.

2. Production of a Thermal Insulation Plaster Containing Aerogel

[0186] A plastering mortar, consisting of [0187] hydraulic lime (21 parts by weight), [0188] white Portland cement (3 parts by weight), [0189] perlite (55 parts by weight), [0190] aerogel with a particle size in the range from 0.5 to 3 mm (20 parts by weight) as well as [0191] additives (1 part by weight), [0192] with a bulk density of 250 kg/m.sup.3 is processed by making it up with water to produce an insulation plaster. [0193] 50 liters of the plastering mortar are made up with 15 liters of water, 40 liters of fresh mortar being obtained. [0194] The thermal insulation plaster containing aerogel has a thermal conductivity of 0.034 W/(mK). The water absorption coefficient w is 1.24 kg/(m.sup.3.Math.h.sup.0.5), i.e. the plaster is water-resistant.

3. Production of a Composite Thermal Insulation System

[0195] a) Production of a Thermal Insulation Panel [0196] A 1 m0.5 m wood construction in panel form with a honeycomb internal construction, having a cell width of 22 cm, is closed on one side by adhesion by means of a fiberglass fabric with a mesh size of 22 mm. The cells of the internal construction are filled with a coarse-grained aerogel with particle sizes in the range from 3 to 5 mm and also the second surface of the basic design is closed by adhesion by a fiberglass fabric with a cell width of 22 mm.

[0197] b) Application of a Composite Thermal Insulation System [0198] A total of 9 thermal insulation panels are applied in an arrangement of 33 thermal insulation panels, i.e. in each case three thermal insulation panels one above the other and three thermal insulation panels adjacent to one another, applied to a wall by means of a 2-component-polyurethane bonding adhesive. The adhesion takes place at certain points. The thickness of the thermal insulation panel is 5 cm. Then a 2 cm thick layer of the insulation plaster produced under 2. and containing an aerogel is applied and then provided with a fiberglass reinforcement made of a fiberglass fabric with a mesh size of 1010 mm. After drying of the thermal insulation plaster layer a further thermal insulation plaster layer, which contains no aerogel, is applied with a layer thickness of 0.5 cm. The further thermal insulation plaster is a purely mineral plaster based on perlite, which is obtained from a plastering mortar containing 50 to 80% by volume of perlite, 10 to 30% by volume of lime, 3 to 5% by volume of cement and 0.1% by volume of cellulose by making it up with water. [0199] After drying of the further thermal insulation plaster layer the surface of the composite thermal insulation system is provided with a primer coat. Finally a surface coating based on acrylate in the form of an aqueous acrylate dispersion is applied with a dry layer thickness from 200 to 300 m. The surface coating is water-repellent and impermeable to driving rain as well as open to diffusion.

4. Production of a Thermal Insulation Plaster Panel

[0200] The thermal insulation plaster produced under 2.) is cast into a 35 to 37 mm thick pane. The cured thermal insulation plaster panel has a dry bulk density of 0.25 g/cm.sup.3 and a thermal conductivity of 0.034 W/(mK). The compressive strength is 0.6 N/mm.sup.2. [0201] The water absorption coefficient w is 1.24 kg/(m.sup.2.Math.h.sup.0.5) and the water vapor diffusion resistance is 6.1. Thus the thermal insulation plaster panel according to the invention is open to water vapor diffusion and is already water-resistant without further treatment. [0202] The thermal insulation plaster panel can be stored and transported without problems, i.e. it is stable enough to withstand mechanical stresses occurring during transport. Furthermore the thermal insulation plaster panel according to the invention can be trimmed and assembled in an outstanding manner, so that it is particularly suitable for internal fitting.

LIST OF REFERENCE SIGNS

[0203] 1 insulation plaster layer, containing aerogel [0204] 2 building wall [0205] 3 insulation plaster system [0206] 4 surface coating [0207] 5 primer layer [0208] 6 further insulation plaster layer [0209] 7 support layer [0210] 8 composite thermal insulation system [0211] 9 thermal insulation panel [0212] 10 bonding adhesive [0213] 11. narrow surfaces of the thermal insulation panel [0214] 12 internal structure of the thermal insulation panel [0215] 13 interstices [0216] 14 sheet material