DE102007042000A1 - Component and structural system comprises hydrophobic microporous thermal insulation, where thermal insulating material is micro-porous thermal insulating material, which is injected or compressed without binders to plates or molded parts - Google Patents

Abstract

The component and structural system comprises hydrophobic microporous thermal insulation. The thermal insulating material is micro-porous thermal insulating material, which is injected or compressed without binders to plates or molded parts, and is shifted before shaping with organosilane. The microporous thermal insulating material comprises 5-98, preferably 50-92 wt.% of pyrogene silicic acid or silicon dioxide aerogels, 3-40, preferably 5-20 wt.% of an opacifier, 0-20, preferably 1-8 wt.% of fibers, and 0-65, preferably 10-40 wt.% of inorganic additives. The organosilane has general formula (I or II). R n-Si-X (4-n) R 3Si-Y-SiR 3 n : 1, 2 or 3; Y : NH or O; R 3-CH, -C 2H 5 or H; X : Cl, Br, -OCH 3, -OC 2H 5 or -OC 3H 8. An independent claim is also included for a method for manufacturing the component, which involves manufacturing a single-shell or two-shell component with vertical holes, in assembled condition.

Description

The thermal insulation of buildings, to save heating energy, has achieved a high priority against the background of dwindling fossil energy resources and the need to reduce CO ₂ emissions. These increasing demands on an optimization of the thermal insulation protection for buildings, applies equally to new buildings, as well as to existing buildings.

State of the art:

building materials like steel, concrete, brickwork and glass, but also natural stones relatively good heat conductor, so that the built from it Exterior walls of buildings in cold weather very quickly the heat from the inside to the outside submit.

The Development is therefore on the one hand, to improve the insulation properties by increasing the porosity of these building materials, such as As in concrete and brickwork, and on the other to the panel the exterior walls with thermal insulation materials, such as B .:

Organic thermal insulation materials

• • Foamed plastics such as polystyrene, Neopor, polyurethane
• • Wood fiber material such as wood wool and cork
• • vegetable or animal fibers such. B. hemp, Flax, wool

Inorganic thermal insulation materials

• • mineral, glass wool, foam glass in plate form
• • Calcium silicate and gypsum boards
• • mineral foams, such as aerated concrete, pumice, Perlite and vermiculite

These listed conventional thermal insulation materials are used, primarily in the form of foamed or pressed plates, together with other layers, as a composite system for facade insulation. However, they show the following weaknesses in detail:
All of these substances have too low and non-sustained thermal insulation effectiveness for today's high demands. The thermal conductivity is consistently above 0.040 W / mK and therefore have a high space requirement.

Other disadvantages are

• • too high water absorption, bad moisture behavior
• • Time consuming and costly attachment the facade (eg glue, dowel, screw, attach of carrier systems, etc .; here are thermal bridges partly pre-programmed)
• • additional composite layers z. B. for liability of plastering necessary
• • with organic insulating materials comes the flammability in addition

• • Wenn diese evakuierten Paneelen – was in der rauen Baubranche an der Tagesordnung ist – durch Beschädigungen belüftet werden, so bedeutet dies das Ende der sehr guten Wärmedämmung
• • Durch die notwendigen, gasundurchlässigen Barrieren sind die Paneelen nicht atmungsaktiv
• • Handling und Verarbeitbarkeit vor Ort sind schwierig, bzw. nicht möglich
• • Bei kleinen Einheiten werden, durch Bildung von Wärmebrücken, die guten Dämmeigenschaften weitgehend wieder aufgehoben.
• • Die Lebensdauer ist durch die Diffusionsmöglichkeit von Gasen, durch die Barriere in die Vakuumpaneele, zeitlich begrenzt.

Very good insulation characterize the vacuum insulation panels, also known as VIP. With a thermal conductivity of about 0.004 to 0.008 W / mK (depending on the core material and negative pressure), the vacuum insulation panels have an 8 to 25 times better thermal insulation effect than conventional thermal insulation systems. They therefore enable slim constructions with optimal thermal insulation. However, this VIP technology has the following serious disadvantages:

• • Ventilation of these evacuated panels - which is the order of the day in the rough construction industry - is the end of the very good thermal insulation
• • Due to the necessary, gas-impermeable barriers, the panels are not breathable
• • Handling and processability on site are difficult or not possible
• • In small units, the formation of thermal bridges largely removes the good insulating properties.
• • The lifetime is limited by the diffusion of gases through the barrier into the vacuum panels.

Hollow blocks with integrated thermal insulation have the advantage that the brick house character is retained during construction. Here are the cavities of the block with porous thermal insulation materials such as Styrofoam foam or Perlite foam filled. Despite the good thermal insulation character of the integrated thermal insulation filling, this advantage is lost again due to the high thermal conductivity of the bodywork, especially in the area of the webs.

• • sehr geringe, anhaltende Wärmeleitzahl (λ ~ 0,018–0,020 W/mK), daher geringer Raumbedarf
• • keine Feuchtigkeitsaufnahme
• • gute Atmungsaktivität, daher kein Feuchtigkeitsstau
• • Vermeidung von Wärmbrücken durch uneingeschränkte Maß-Möglichkeiten
• • Brandklasse (A1 und A2)
• • Ziegelhauscharakter des Gebäudes bleibt erhalten
• • langer Lebenszyklus

A thermal insulation system has now been found which largely eliminates these existing deficiencies and therefore has clear advantages.

• • very low, continuous thermal conductivity (λ ~ 0.018-0.020 W / mK), therefore small space requirement
• • no moisture absorption
• • good breathability, therefore no moisture retention
• • Avoidance of thermal bridges through unrestricted measure possibilities
• • Fire class (A1 and A2)
• • Brick house character of the building is retained
• • long life cycle

The Insulation system according to the invention is a double-shell masonry with integrated core of hydrophobic, microporous core materials.

Microporous Thermal insulation materials are included as base material highly dispersed substances as Konvektionsblocker whose particle size in the nano range and opacifiers for adsorption and reflection of heat radiation. There are also fibers, to strengthen the system. Preferred as base materials fumed silicas. According to the invention Therefore, these hydrophilic Dämmmstoffe implemented with organosilanes and thereby made hydrophobic.

fumed Silicas are volatile by flame hydrolysis Silicon compounds such. As organic and inorganic chlorosilanes produced. These fumed silicas are characterized by a high porous structure. Other components of this mixture are compounds that radiate heat in the infrared range adsorb, scatter and reflect. you will be commonly referred to as opacifiers. Preferably have these opacifiers in the infrared spectral range a maximum between 1.5 and 10 microns. The particle size this particle is preferably between 0.5-15 microns. Examples of such substances are titanium oxides, zirconium oxides, Ilmenite, iron titanate, iron oxide, zirconium silicate, silicon carbide, manganese oxide and soot.

to Reinforcement, ie mechanical reinforcement, becomes fibers with inserted. These fibers can be inorganic or of organic origin.

Examples for inorganic fibers are glass wool, rock wool, basalt fibers, Slag wool and ceramic fibers resulting from melting of aluminum and / or silica, and other inorganic metal oxides consist. Pure silica fibers are z. B. silica fibers. organic Fibers are z. As cellulose fibers, textile fibers or plastic fibers. The following dimensions are used: diameter 1-12 μm, preferably 6-9 μm; Length 1-25 mm, preferably 3-10 mm.

For technical and economic reasons, inorganic filler materials can be added to the mixture. Various synthetic synthesized modifications of silica such as. For example, silica aerogels, precipitated silicas, arc silicas, SiO ₂ -containing flue dusts caused by oxidations of volatile silicon monoxide, which arise in the electrochemical production of silicon or ferrosilicon. Likewise silicic acids which are obtained by leaching of silicates such as calcium silicate, magnesium silicate and mixed silicates such. B. olivine (magnesium iron silicate) can be prepared with acids. Furthermore, naturally occurring SiO ₂ -containing compounds such as diatomaceous earths and kieselguhr are used.

Also can be used: thermally inflated Minerals like perlite and vermiculite. Depending on your needs can finely divided metal oxides such as aluminum oxide, titanium dioxide, iron oxide be added.

In addition, lightweight organic fillers such as fibers or sawing waste resulting from the processing of organic foams such as polyurethane or polystyrene may be added. These materials have low densities (<100 kg / m ³ ) and thus do not increase the density of the microporous insulation core.

The core material not only has to repel water, but also the attachment and absorption of Prevent moisture.

The cause of this moisture absorption are the silanol groups placed on the silica, where the water accumulates. It is known ( DE3037409 A1 ), Core materials consisting of foamed perlites to make water repellent with alkali and / or alkaline earth metal stearates, siliconates, waxes and fats. These substances are mainly used for surface coverage, which is commonly known as "coating." The core materials treated in this way are repellent to liquid water, but absorb water vapor, in the form of atmospheric moisture, and thus lead to a deterioration of the insulation properties.

From the DE 4221716 A1 For example, it is known to react fumed silicas with organosilanes and thus make them hydrophobic, ie water-repellent. However, such hydrophobic silicic acids can not be sufficiently densified and are not compressible, since interleaving of the silicic acid particles of the silanol groups by saturation with organic groups is no longer possible. Likewise, a compression of a mixture provided with hydrophobic silica is not possible.

The Hydrophobization of microporous thermal insulation materials happens according to the invention with organosilanes. at This reaction finds a reaction of the silanol groups of the silica with the water-repellent organosilyl groups of silanes instead. These Implementation can be both first, immediately before compression or / and during the pressing process, as well as secondly, after the Compression take place.

Prefers Being the first option will be less procedural steps and thus easier and more economical to perform is. In both variants, the compression to panels without Binder additive instead.

As already described in the patent application (no. 10 2007 020 716.8) is, the addition of organosilanes in liquid form during the mixing process at the end of the mixing sequence, immediately before the compression. It is neces sary that an intimate mixing the various components is guaranteed.

The Reaction of the organosilanes with the silanol groups of the silica takes place during the pressing process or immediately after that. The reaction of silanes with the microporous Insulating material can be supplied by heat be accelerated. This can be done by heating the Press stamp during the pressing process or, immediately after pressing, by briefly heating the panels yourself. The applied temperatures are included 40-90 ° C, preferably 50-70 ° C.

As already described above, it is possible to use compressed, hydrophilic, microporous moldings in an additional Step to hydrophobic with organosilanes. This can be done by Implementation of silanes in gaseous or liquid Form done. The latter method can destroy the Silica structure lead and is therefore unsuitable. The reaction is under the gaseous admission under elevated temperatures of 70-160 ° C and under light to medium overpressure (0.2-2.5 bar), z. B. performed in an autoclave.

The in both production methods (hydrophobing before and after pressing) resulting cleavage products such. As ethanol, hydrogen chloride or Ammonia, can be obtained by subsequent heating the hydrophobized plates to 50-85 ° C become.

By Addition of small amounts of polar substances such as water and alcohol in both processes, the reaction rate can also be be accelerated. An addition of binders to increase the plate strength is undesirable, as this is the thermal insulation properties influence negatively.

The used organosilanes have compared to the conventional Water repellents such as stearates, siliconates waxes and fats, etc., the decisive advantage that they are easily vaporizable. The Vapor pressures of the organosilanes used are in between 20 and 250 hPa at 20 ° C. The boiling points of usable Organosilanes are between 40 and 130 ° C. This is optimal distribution of organosilanes on the microporous Thermal insulation mixture, without destruction ensured the silica structure.

Use is made of compounds of the formulas R _n -Si-X _4-n where n = 1, 2 or 3
or
R ₃ Si-Y-SiR ₃ where Y may be NH or O.
R = -CH ₃ and / or H
-C ₂ H ₅
X = Cl or Br
-OCH ₃
-OC ₂ H ₅
-OC ₃ H ₅
Such compounds are for. B. (CH ₃ ) ₃ SiCl [trimethylchlorosilane];
(CH ₃ ) ₂ SiCl ₂ [dimethyldichlorosilane];
CH ₃ SiCl ₃ [monomethyltrichlorosilane] or (CH ₃ ) ₃ SiOC ₂ H ₅ [trimethylethoxysilane];
(CH ₃ ) ₂ Si (OC ₂ H ₅ ) ₂ [dimethyldiethoxysilane];
CH ₃ Si (OC ₂ H ₅ ) ₃ [methyltriethoxysilane] and (CH ₃ ) ₃ SiNHSi (CH ₃ ) ₃ [hexamethyldisilazane];
(CH ₃ ) ₃ SiOSi (CH ₃ ) ₃ [hexamethyldisiloxane].
According to the invention, preference is given to trimethylethoxysilane, dimethyldiethoxysilane, methyltriethoxysilane, hexamethyldisilazane

The Addition of silanes depends on the specific surface area (BET surface area) of silicas, their proportion on the mixture, as well as the type of silanes. The addition amount is between 0.5-10 wt .-% of the mixture, preferably between 1 and 6% by weight. The silanes are added during the mixing process in liquid form, it is necessary that an intimate Mixing of the individual components takes place.

The Production of the microporous insulation mixture can generally take place in various mixing units. Prefers However, planetary mixers are used. It is advantageous the fibers first with a portion of the second mixing components as to mix in a kind of "masterbatch" to make it a complete one Unlock the fibers to ensure. To the fiber digestion is the addition of the largest Part of the mixing components. In the insito-hydrophobized plates the addition of the liquid silanes happens last in the mixing sequence.

immediate after completion of the mixing process, the mix is to dimensionally accurate Pressed plates.

The Density of these plates can, depending on the choice of components, between 100-450 g / l, preferably 150-300 g / l.

The λ values lie in the range of only 17-22 mW / mK. In comparison, Perlite with a bulk density of 120 g / l, depending on setting agent 45-60 mW / mK.

plate size and plate thickness can be customized, depending on Need to be adjusted. If necessary local adaptation can the panels are reworked in length measures become.

The hydrophobic panels are used in double-shell masonry from brick, concrete and lightweight concrete walls or in structural elements such as B. plasterboard.

Bivalve masonry systems

at a double-shell masonry is a masonry with two wall shells with a gap. So that the individual shells steadier, they are periodically through Masonry anchors or composite tiles connected together. The gap between the two walls of the wall should be as narrow as possible be kept and do not exceed 15 cm.

Of the Interspace can with the already mentioned above thermal insulation materials be filled.

According to the invention for thermal insulation panels with microporous, hydrophobic thermal insulation core between the two Wall shells inserted. The space between the two Wall shells can be adapted to the respective thickness of the insulating material can be adjusted, but also in addition with an air gap be provided.

Instead of a panel of the desired insulation thickness, two panels with half the thickness of insulation can be used be installed offset from each other. As a result, any thermal bridges are avoided. With dimensional accuracy of wall gap and panels can be dispensed with anchoring the same, otherwise reaches a selective foaming with PUR foam for fixing the thermal insulation. It is also possible to combine the hydrophobic, microporous thermal insulation with panels of other materials.

By the breathability of the panels used can a Ventilation of the double-shell system is eliminated. To thermal bridges to avoid, where appropriate, the use of metallic Wall anchors are dispensed with. This is possible if composite tiles to stabilize the system. These composite tiles can be made of hollow bricks with integrated thermal insulation consist, in particular but from hollow building blocks with integrated, hydrophobic, microporous thermal insulation (see patent application no. 10 2007 020 716.8).

The Area size of the thermal insulation panels used depends on the brick size used and the number of building blocks per area to be fixed beforehand. Ideally, the panel surface size be chosen so that always after a certain wall height (3 or 4 bricks), a series of composite tiles, with integrated thermal insulation core to avoid larger thermal bridges, can be walled up. Ideally, per area of 4 × 3 bricks (size per tile approx. 25 × 25 cm) a thermal insulation board of about 100 × 75 cm area size be used.

The Strength of the overall system - bivalve wall including insulation - can be chosen so that a composite brick thickness the same size as the total wall thickness.

At the Walls of the bivalve system are allowed according to the invention Panels come into contact with wet mortar and water, without a water absorption in the insulating material takes place and thus a deterioration of the insulation effect occurs. The panels are easy to handle during installation and can open the necessary dimension and configuration are reworked.

The bivalve thermal insulation composite wall system according to the invention is breathable and does not cause moisture build-up and resulting mold growth.

With the insulation system according to the invention is a slender, if desired, at the same high life cycle Wall construction with preservation of the "brick house character" or, if desired, for larger insulation thicknesses, a highly efficient thermal insulation towards passive and zero energy homes, given.

EXAMPLES

in the The following are an example of the invention hydrophobic, microporous thermal insulation material in bivalve masonry (A) and a comparative example conventional core material (B - foamed Perlite).

The Mixtures were carried out in a cyclone mixer at 3000 rpm.

To measure the thermal conductivity (λ value), a molded article having the dimensions of 1,000 × 750 × 60 mm was pressed from the mix on a hydraulic press at a pressure of about 50 kg / cm ² . Mixture A: recipe: Pyrogenic silica (BET surface area 200 m ² / g) 70% by weight Glass fiber (length 6 mm, thickness 7 μm) 3% by weight Rutile (particle size approx. 10 μm) 25% by weight Trimethylethoxisilan 2% by weight Weight of the total mixture: 10,000 g

300 g fibers, 750 g of rutile and 2,000 g of silica were initially 3 min, premixed to disintegrate the fibers.

Subsequently the rest of the solid components (5,000 g of silica, 1,750 g of rutile) was added and mixed for a further 2 min. In this mixture Then 200 g of trimethylethoxysilane were added and another Minute stirred.

The finished mixture 9,000 g were removed and pressed to a solid body of the external dimensions of 1,000 × 750 × 60 mm. This shaped body was then heated at 80 ° C. for 3 minutes. Mixture B: recipe: Foamed pearlite 68% by weight Potash water glass 32% by weight Weight of the total mixture: 10,000 g

• * gemessen an einer ausgesägten Platte der Größe 25 × 25 cm

The components were mixed for 5 minutes in the same mixing unit as (A). 9,900 g of the mixture was pressed into a shaped article having the same outer dimensions as (A) and then heated at 150 ° C. for 20 minutes. Results: mixture Dimensions (mm) Weight (g) Bulk density kg / m ³ λ value W / mK A 1,000 × 750 × 60 9000 200. 0,018 * B 1,000 × 750 × 60 9900 220 0,054 *

• * measured on a sawed plate of size 25 × 25 cm

in the Composite system in double-shell masonry is the following arrangement accepted:

Mixture A

• a) Masonry front shell: 16.5 cm brick with λ value = 0.68 W / mK
• b) Hydrophobic, microporous insulation: 6 cm with λ value = 0.018 W / mK
• c) masonry back shell: 16.5 cm brick with λ value = 0.68 W / mK This results in a calculated K value of 0.26 W / m ² K

Mixture B

• a) Masonry front shell: 16.5 cm brick with λ value = 0.68 W / mK
• b) Perlite insulation: 6 cm with λ value = 0.054 W / mK
• c) masonry back shell: 16.5 cm brick with λ value = 0.68 W / mK This results in a calculated K value of 0.63 W / m ² K.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 3037409 A1 [0017]
• - DE 4221716 A1 [0018]

Claims (13)

Two-shell masonry with hydrophobic, microporous thermal insulation, characterized in that the space between the two shells, filled with panels of hydrophobic, microporous thermal insulation materials, which are pressed without binder and are hydrophobicized with the addition of organosilanes. Clam-shell masonry with integrated hydrophobic, Microporous thermal insulation according to claim 1. characterized in that the microporous thermal insulation material, in the last mixing sequence, just before pressing organosilanes be supplied. Clam-shell masonry with integrated hydrophobic, Microporous thermal insulation according to claim 1. characterized in that the hydrophobization with organosilanes after compression of the microporous thermal insulation mixture takes place. Clam-shell masonry with integrated hydrophobic, Microporous thermal insulation according to claim 1. to 3. characterized in that the used for hydrophobing Organosilane boiling points, which at normal pressure between 45 ° C. and 130 ° C lie Bivalve masonry with integrated hydrophobic microporous thermal insulation according to claim 1 to 4, characterized in that the organosilanes used have the following structural formulas: Compounds of the formulas R _n -Si-X _{4-n are used,} where n = 1, 2 or 3 may be or R ₃ Si-Y-SiR ₃ wherein Y may be NH or O R = -CH ₃ -C ₂ H ₅ ; and / or HX = Cl or Br -OCH ₃ ; -OC ₂ H ₅ ; -OC ₃ H ₈ Clam-shell masonry with integrated hydrophobic, Microporous thermal insulation according to claim 1. to 5, characterized in that the microporous heat insulation panels have the following composition: • fumed silica 5-95% by weight, preferably 20-75% by weight • opacifiers 5-50% by weight, preferably 10-35% by weight • fibers 0-20% by weight, preferably 1-8% by weight. • finely divided Inorganic additives 5-65 wt .-%, preferably 10-40% by weight Clam-shell masonry with integrated hydrophobic, Microporous according to claims 1 to 6, characterized the following opacifiers are used: titanium oxides, Zirconium oxides, ilmenite, iron titanate, iron oxide, zirconium silicate, silicon carbide, Manganese oxide and carbon black, preferably ilmenite, titanium dioxide, Zirconium silicate, silicon carbide. Clam-shell masonry with integrated hydrophobic, Microporous thermal insulation according to claim 1. to 7, characterized in that fibers, preferably inorganic Fibers are used. Bivalve masonry with integrated hydrophobic, microporous thermal insulation according to claim 1 to 8, characterized in that the following additives are used: synthetically produced modifications of silica such. Example, precipitated silicas, silica aerogels, arc silicas, SiO2-containing fly ash from electrochemical silicon production. As well as naturally occurring SiO ₂ -containing compounds such as diatomaceous earth and diatomaceous earth, thermally inflated minerals such as perlite and vermiculite, further finely divided metal oxides such. B. alumina. Clam-shell masonry with integrated hydrophobic, Microporous thermal insulation according to claim 1. to 9th characterized in that the density of the compressed mixture 100-450 g / l, preferably 120-300 g / l. Two-shell masonry with integrated hydrophobic, microporous thermal insulation according to the above claims, characterized in that the shell material, one or both sides, brick, natural stone, sand-lime brick, concrete blocks and slabs, aerated concrete block, wood, clinker, calcium silicate plates, Gipsplat can exist. Clam-shell masonry with integrated hydrophobic, Microporous thermal insulation according to the above claims characterized in that to reinforce the construction Masonry anchors and composite blocks can be used. Clam-shell masonry with integrated hydrophobic, Microporous thermal insulation according to claim 12. characterized in that the composite blocks hollow bricks with integrated thermal insulation are.