Foam masses

Abstract

Combination comprising a composition A and a composition B, wherein the composition A contains hollow microspheres and the composition B contains a solvent for opening these hollow microspheres and the composition A and / or the composition B contains an inorganic and / or organic binder, the hollow microspheres having a polymer shell and containing a propellant, the combination being in a 2-component cartridge.

Description

[0001] The invention relates to foam compounds, in particular non-combustible foam compounds, which can be used, for example, in construction. The foam compounds can be produced from a combination of a composition A and a composition B (two-component system) contained in a two-component cartridge.

[0002] Lightweight panels are well-known in the construction industry. Polystyrene panels are often used, but these are highly flammable. Therefore, there is a need for cost-effective, yet non-combustible insulation materials. Suitable options include panels made of mineral wool (stone wool, glass wool), wood wool, or even foam glass panels.

[0003] Foam glass bodies made from liquid water glass, fillers, and peroxides are known. The peroxides decompose into oxygen in the alkaline water glass, thereby foaming the mixture [US 3095312 A]. To avoid the use of reactive peroxides, an alternative process is used in which an acidic hardener is added, which hardens the water glass and simultaneously releases a gas, such as CO2. This gas and the addition of surfactants cause the mixture to foam. The disadvantage of this process is that the gas-releasing reaction leads to heating of up to 100 °C [US 3850650 A]. Another process does not require a foaming agent in the water glass composition. Foam glass is created solely through the rapid heating of the contained water and the resulting gas bubbles [US 6497945 B1].

[0004] US Pat. No. 8,822,557 B2 discloses an elastic foam made of organic and inorganic components. This results in a mineral foam with improved mechanical properties and water resistance, which contains a mineral binder and a polymer dispersion.

[0005] DE 101 41 777 A1 discloses a non-combustible, inorganic foam that is moisture-resistant and elastic. The foam is based on a mixture of an alkali metal silicate, an alkali metal aluminate, and a blowing agent. The process for producing the inorganic foam requires the application of heat.

[0006] DE 32 44 523 A1 discloses the production of an in-situ foam from water glass and a hardener solution without the addition of heat. The two components, water glass and hardener solution, are contained in two pressurized containers; foam generation occurs, among other things, using a liquid propellant gas under increased pressure at 0-50°C. The in-situ foam is suitable for the production of non-flammable filling or insulation materials in construction, for example. A carboxylic acid ester can also be used as a hardener. After hardening, the foams are classified as building material class A2 (DIN 4102).

[0007] The object of the present invention is to provide foam compositions that overcome at least one disadvantage of the prior art. In particular, a system for producing in-situ foam is to be provided, i.e., a foam that is formed without the external supply of heat. The building materials (especially lightweight panels) that can be produced using the foam compositions should be as fire-resistant as possible and / or exhibit good flexural strength. Good thermal insulation is also particularly advantageous.

[0008] The object of the invention is achieved by the inventive combination according to claim 1, which comprises a composition A (also called the "main component") and a composition B (also called the "initiator"). After combining (e.g., stirring) composition A with composition B, the mixture foams and subsequently cures. The foaming time can be varied by varying the concentration ratios of the components. The foam mass is then available for the production of building materials, in particular construction foams or building boards.

[0009] A particular advantage of the invention is that foaming can occur even without external heat input. The combination can therefore be "cold-foamed." Foaming can preferably take place at temperatures below 50°C, more preferably below 40°C, or even below 30°C, particularly preferably at room temperature. This allows foaming to take place on-site at a construction site. Thus, the invention provides, in particular, a two-component system for producing an in-situ foam. Composition A (main component)

[0010] Composition A comprises hollow microspheres. In a particular embodiment, composition A comprises an inorganic and / or organic binder and hollow microspheres. It may also contain at least one filler (preferably inorganic minerals), at least one fiber, water, a base (e.g., sodium hydroxide or potassium hydroxide), and / or at least one defoamer. The fillers serve to minimize shrinkage and / or cracking of the finished product after drying. They can also improve the mechanical properties of the product.

[0011] Filler, fiber, water, base and / or defoamer may be included alternatively or additionally in composition B.

[0012] If composition A does not contain an inorganic and / or organic binder, composition B contains an inorganic and / or organic binder. It is also possible that both composition A and composition B contain an inorganic and / or organic binder.

[0013] The hollow microspheres in the main component contain a blowing agent and have a polymer shell.

[0014] After adding composition B (initiator), the polymer shell is opened by a solvent, i.e., the polymer shell is at least partially dissolved or dissolved, releasing the blowing agent contained in the hollow microsphere. The mixture thus foams.

[0015] The hollow microspheres and the solvent are therefore functionally separated before composition A and composition B are brought together. They are functionally separated if the polymer shell of the hollow microspheres dissolves or dissolves essentially only after composition A and composition B are brought together. This is ensured by the hollow microspheres and the solvent being present in different compositions (A and / or B) or being separated from each other in some other way. The composition (A and / or B) of the inorganic and / or organic binder is irrelevant.

[0016] The water can be used to adjust the viscosity and drying rate / reaction time. Basic additives, such as NaOH or KOH, increase the pH value and can catalyze the curing reaction. Small additions of commercially available defoamers can regulate the pore size and pore distribution in the desired direction and prevent excessively large pores or air bubbles, which can lead to technical problems during processing and also reduce the flexural strength of the sheets or molded bodies.

[0017] In summary, Table 1 shows the possible components of composition A and their respective functions. These components may be included additionally or alternatively in composition B. Table 1: Components of composition A with function. ingredient function binder Hardening of the mixture of composition A and composition B Fillers Reduction of shrinkage, improvement of mechanical properties Fibers Improvement of mechanical properties Hollow microspheres with propellant Foaming after addition of composition B Water Adjustment of viscosity and drying speed / reaction time base Catalysis of curing and foaming, adjustment of reaction time Defoamers Regulation of pore size and distribution Plastic dispersion Improvement of elasticity and water resistance; can be included in addition to the binder and / or as a binder binder

[0018] The organic and / or inorganic binders can harden or crosslink through physical or chemical processes. The binder is therefore preferably hardenable or crosslinkable. In physical hardening, the binder is suspended, for example, in a solvent. Hardening then occurs, for example, through the evaporation or drying of the solvent. Examples include polyolefins, vinyl polymers (e.g., polyvinyl acetate, polyvinyl alcohol), styrene-butadiene copolymers, and polyacrylates (acrylic resins). Acrylic resins are based, for example, on polymers or copolymers of acrylic acid, methacrylic acid, and their esters. They are copolymerized, for example, with other unsaturated monomers, such as styrene or acrylonitrile.

[0019] Chemical hardening is based on a chemical reaction; it is also called crosslinking, resinification, gelation, or polymerization. Chemical hardening can occur, for example, through oxidation and subsequent polymerization (e.g., drying oils, natural resins, alkyd resins, or epoxy esters), through polymerization (e.g., polyester), through polycondensation (e.g., alkali silicates, phenolic resins, urea resins, and melamine resins), through polyaddition (e.g., with reactive resins such as polyurethane and epoxy resin), or through chain polymerization.

[0020] Other possible binders are SBR latices, natural latex, neoprene latex, cement or gypsum.

[0021] Possible types of cement include: The European standard DIN EN 197-1 distinguishes between 27 so-called common cements, which are divided into five categories according to their main components. These are: - CEM I: Portland cements - CEM II: Portland composite cements - CEM III: Blast furnace cements - CEM IV: pozzolanic cements - CEM V: Composite cements

[0022] The main cement types are divided according to their main components into the cement types according to DIN EN 197-1 and special cements VLH according to DIN EN 14216: - Portland cement CEM I - Portland slag cement CEM II / -S - Portland silica fumed cement CEM II / -D - Portland pozzolanic cement CEM II / -P and CEM II / -Q - Portland fly ash cement CEM II / -V and CEM II / -W - Portland slate cement CEM II / -T - Portland limestone cement CEM II / -L and CEM II / -LL - Portland composite cement CEM II / -M - Blast furnace cement CEM III / VLH III - Pozzolana cement CEM IV / VLH IV - Composite cement CEM V / VLH V

[0023] Portland cement is preferred, but other types of cement can also be used. The specialist can select the appropriate cement type depending on the application.

[0024] Examples of gypsum types that can be considered include: - stucco - plaster - mortar plaster - Adhesive plaster - Machine-applied gypsum plaster - Joint plaster - Plaster of Paris - screed gypsum - Ready-mixed plaster - Polymer gypsum

[0025] Adhesive plaster is preferred, especially Rotband.

[0026] In one embodiment, the inorganic and / or organic binder is a plastic and is present as a dispersion. Suitable plastic dispersions include all of the aforementioned plastics, in particular styrene-butadiene copolymers (especially styrene-butadiene acrylate), acrylate dispersions, polyvinyl acetate dispersions, SBR latices, natural latex, neoprene latex, polyurethane dispersions, or epoxy resin dispersions. Plastic dispersions that are alkali-resistant or cement-compatible are particularly preferred. Foams containing a plastic dispersion exhibit high elasticity and low density. This applies even when the plastic dispersion is used in addition to another binder, but also when the plastic dispersion is used as a binder.

[0027] Liquid plastics in non-aqueous systems are also possible, such as liquid silicone resin or polyurethane systems. A hardener is preferably added to these to fix the foam structure.

[0028] Chemical hardening or crosslinking may require the addition of a hardener, e.g., a carboxylic acid ester, a crosslinking agent (e.g., sulfur, peroxides, or metal oxides in the vulcanization of rubber), a catalyst (e.g., acid or siccatives), or the application of heat or UV radiation. Chemical hardening, particularly the hardening of cement or gypsum, may require the addition of a setting accelerator. Examples of setting accelerators for cement include calcium chloride; alkaline carbonates such as sodium carbonate, potassium carbonate, calcium carbonate; aluminates such as tricalcium aluminate; calcium ammonium nitrate; calcium nitrate, or basic ammonium salts.

[0029] Examples of setting accelerators for gypsum are calcium sulfate dihydrate (preferably finely ground) or potassium sulfate.

[0030] Physical hardening is also conceivable, for example, by removing water. Desiccants or superabsorbents are suitable for this. By removing the water, it is possible to quickly stabilize the foam and prevent it from collapsing. Burnt lime is particularly suitable because, in addition to binding the water, it provides a large amount of heat during its reaction. The released heat, combined with the binding of the water, leads to accelerated setting and stabilization of the foam.

[0031] If the binders such as plastic dispersions, cement or gypsum cannot react directly with the solvent, for example with 4-methyl-1,3-dioxolan-2-one, hardeners can be used to harden and stabilize the foam.

[0032] For example, foams based on hydraulically curing, inorganic binders, such as cement, can react with the water of the other composition. To accelerate this reaction, hardeners such as setting accelerators can be used.

[0033] To stabilize a foam containing a plastic dispersion as a binder, hardeners that react with or bind water can be used in the anhydrous composition. Suitable for this purpose are hydraulic binders such as cement or hydraulic lime. Cement can therefore be used both as a binder and as a hardener. Additives that can bind large amounts of water, such as desiccants or so-called "superabsorbents," are also suitable. Burnt lime is particularly suitable because, in addition to binding the water, it also releases a large amount of heat during its reaction. The released heat, combined with the binding of the water, leads to accelerated setting and stabilization of the foam.Due to the alkalinity of the inorganic binders / hardeners in water, plastic dispersions are preferably used in this embodiment, which show great stability in alkaline environments.

[0034] The binder, as a polymer dispersion, can also harden through coagulation. This can be physically or chemically induced, for example, shear-induced or through the addition of acids or bases. For example, a plastic dispersion, such as SBR latices, can harden through controlled or targeted coagulation. Examples of suitable additives include sodium silicofluoride, ammonium acetate / ammonia by lowering the pH, or by adding electrolytes such as sodium chloride, calcium chloride, sulfates, or other salts. The skilled person can select suitable additives.

[0035] In a preferred embodiment of the invention, the binder is chemically crosslinked by polycondensation. It is preferably an alkali silicate, particularly preferably a sodium or potassium silicate. Melts of aqueous solutions of alkali silicates are also referred to as water glass. To produce water glass, for example, high-purity quartz sand is melted with alkali carbonate. The two reactants react to form the respective alkali silicate and carbon dioxide. The cooled melt forms a glassy and solid structure, which is ground into a powder. This powder can be dissolved in water at elevated temperature and pressure.

[0036] There are three ways to initiate the hardening of the water glass: 1.) By lowering the pH value, the water glass molecules react with water in an acid-base reaction. As a result, they are no longer present in their alkali salts, the electrostatic repulsion decreases, and they undergo condensation reactions via their silanol groups. 2.) The addition of salts also reduces the repulsion between the negatively charged silanol groups and leads to condensation reactions. In particular, multivalent cations enable the water glass monomers to approach each other, resulting in a subsequent condensation reaction. 3.) The condensation reaction of water glass is an equilibrium reaction. The equilibrium is shifted toward condensation by removing water from the solution. This is achieved by elevated temperatures (thermally) or chemically by adding water-binding substances. Esters can be used, which decompose with water to form an alcohol and an acid. Furthermore, the resulting CO2 leads to hardening of the water glass by reacting with alkali metasilicate according to the following scheme: Me2SiO3 + H2CO3 → Me2CO3 + H2SiO3 (Gel SiO2 n H2O)

[0037] The applications of water glass are diverse. It can be used as a flame retardant because it is highly temperature-resistant and fire-resistant. Water glass is also suitable for sealing surfaces. Therefore, the foams according to the invention are preferably used as surface coatings for paper, textiles, and in building protection. The production of fire-resistant lightweight panels is particularly preferred.

[0038] Examples of binders that can be used include polyolefins, vinyl polymers, styrene-butadiene copolymers, polyacrylates, drying oils, natural resins, alkyd resins, epoxy esters, polyesters, alkali silicates, phenolic resins, urea resins, melamine resins, reactive resins, SBR latices, natural latex, neoprene latex, cement, gypsum, or combinations thereof. All binders allow for the aforementioned applications. They are particularly suitable for the production of fire-resistant lightweight panels.

[0039] Alkali silicates, plastic dispersions, cement or gypsum are preferred as binding agents.

[0040] According to the invention, particularly preferred binders are sodium or potassium silicate (sodium or potassium water glass), in particular with a solids content of 25 to 55%.

[0041] In one embodiment, composition A contains an inorganic binder, in particular an alkali silicate, and an organic binder.

[0042] By foaming the inventive combination, the finished product acquires an advantageously low density and good insulating properties. The resulting pores initially fill with water vapor and, when dry, with ambient air. Due to the low thermal conductivity of the air contained in the pores, the foamed product can act as an effective thermal insulator.

[0043] The product, such as the lightweight construction panel, can be foamed from the inside out and preferably does not require a melt during foaming. This reduces the energy costs of the melt. The panel is therefore comparatively inexpensive to produce.

[0044] Composition A contains hollow microspheres that serve as foaming agents. The hollow microspheres contain a blowing agent. After addition and mixing with the second composition, the hollow microspheres are partially dissolved or dissolved, thereby opening up, and the blowing agent is released. The release of the blowing agent causes the mass to foam and form finely and homogeneously distributed pores.

[0045] The finer the foam's pores, the more stable the molded articles or sheets produced from it are. The foam can be characterized visually, gravimetrically, or based on the resulting volume. Furthermore, the mechanical stability of the finished foam can be determined through tests on a tensile testing machine (see infra, examples).

[0046] The production of a sheet or molded part is preferably carried out by pouring the mixture of compositions A and B before foaming. The mold used for this purpose can optionally be closed and the molded body subsequently removed from the mold. The foam mass can then be dried. The drying parameters can vary depending on the size and shape of the sheet. Drying is not mandatory.

[0047] On average, the pore size of the product can be between 0.05 and 5 mm, preferably between 0.1 and 2 mm, particularly preferably between 0.1 and 1 mm, and particularly preferably between 0.1 and 0.3 mm. With this average pore size, the product, for example, the lightweight building board, can be described as fine-pored [KSW Sing (1985). Pure and Applied Chemistry, 57(4): pp. 603-619].

[0048] The hollow microspheres can have a diameter D 50 of 5 to 100 µm, preferably 5 to 50 µm, more preferably 10 to 30 µm. In a preferred embodiment, the hollow microspheres have a diameter D 50 from 10 to 16 µm. They have a polymer shell and contain a propellant. Polymer shells with a low calorific value are preferred. In principle, any polymer shell that can be dissolved or broken down by a solvent, preferably without the application of heat, and thus opened is suitable.

[0049] The polymer shell comprises a polymer, for example EVA (ethylene-vinyl acetate copolymer); polyvinylidene chloride and / or acrylonitrile; acrylonitrile, methyl methacrylate and / or methacrylonitrile, or combinations thereof; preferably acrylonitrile and / or methacrylonitrile, most preferably acrylonitrile and methacrylonitrile.

[0050] The propellant is preferably a propellant gas. The choice of propellant is unlimited. Propellants that occupy a larger volume after release are preferred. Therefore, liquid propellants may be preferred over gaseous propellants. Propellants that are non-flammable and chemically inert are advantageous.

[0051] Examples of propellants include liquefied gases (liquid at room temperature and low compression, e.g., <10 bar) comprising short-chain hydrocarbons selected from propane, butane, isobutane, pentane, isopentane, or combinations thereof; dimethyl ether, air, CO2, nitrogen, CFCs, or combinations thereof. For example, a mixture of propane and butane can be used. Isobutane is particularly preferred.

[0052] Hollow microspheres are also called microspheres. Examples of hollow microspheres that can be used include Expancel® microspheres from Akzo Nobel, such as Expancel® hollow microspheres of type 461 DU 20, 551 WU 20, 031 WUF 40, or 031 DU 40, particularly preferred types 031 WUF 40 or 031 DU 40. Other manufacturers of hollow microspheres include Kureha and Matsumoto. Fibers

[0053] Composition A may optionally contain fibers, for example, mineral wool, glass fiber, polyacrylonitrile, or natural fibers, e.g., seaweed. Mineral wool or glass fibers, or combinations thereof, are preferably used. The fibers can positively influence the flexural strength of a product made from the combination. The fibers preferably have an average fiber length of 0.05 to 6 mm, particularly preferably less than or equal to 0.25 mm.

[0054] The fibers may also be included additionally or alternatively in composition B.

[0055] The fibers can be included in the combination in a proportion of approximately 0.5-4% by weight of the total formulation. A proportion of approximately 2-3% by weight is preferred. Glass fibers are particularly preferred in a proportion of approximately 2% by weight of the total formulation.

[0056] An average length of less than 0.25 mm is preferred, preferably less than 0.20 mm, and particularly preferably about 0.18 mm. A diameter of about 9-14 µm is preferred.

[0057] Preferably, the optional at least one fiber is mineral wool or glass fiber, has an average length of ≤ 0.25 mm and is contained in the combination in a proportion of 0.5-4 wt.%. Composition B

[0058] Composition B comprises a solvent. The solvent serves to open the polymer shell of the hollow microspheres. To do this, it is at least partially dissolved or dissolved. Therefore, any solvent that can partially dissolve or dissolve the polymer shell of the hollow microspheres used is suitable according to the invention.

[0059] Solvents which can be used according to the invention are preferably selected from the following group: polar solvents such as acetone, nitromethane or dimethyl sulfoxide or organic carboxylic acid esters (R 1 -OC(=O)-OR 2 with R1 ,R 2 = alkyl, allyl and / or aryl radicals) or a combination thereof; preferably a carboxylic acid ester. The carboxylic acid ester can be selected from the following group: dimethoxyformic anhydride, 1,3-dioxolan-2-one, 4-methyl-1,3-dioxolan-2-one, 4-hydroxymethyl-1,3-dioxolan-2-one or combinations thereof; and is preferably 1,3-dioxolan-2-one or 4-methyl-1,3-dioxolan-2-one or a combination thereof.

[0060] Polar solvents with a high dipole moment are particularly suitable for rapidly opening the polymer shell of hollow microspheres, especially when the polymer shell contains acrylonitrile and / or methacrylonitrile. For example, acetone (ε=20) reacts with the polymer shell, but more slowly than 4-methyl-1,3-dioxolan-2-one (ε=65). Therefore, 1,3-dioxolan-2-one and 4-methyl-1,3-dioxolan-2-one are particularly preferred, especially when the polymer shell contains acrylonitrile and / or methacrylonitrile. Both solvents can quickly open the polymer shell.

[0061] Composition B may preferably contain a hardener for curing or crosslinking the inorganic and / or organic binder. The hardener serves to fix the foam structure produced and to cure the binder. Hardeners can be, for example, carboxylic acid esters or setting accelerators. A crosslinking agent (e.g., sulfur, peroxides, or metal oxides in the vulcanization of rubber), a catalyst (e.g., acid or siccatives), or the application of heat or UV radiation can also be used for curing. Crosslinking agents or catalysts are also referred to as hardeners. Depending on the composition, the hardener can also be present in composition A, or alternatively.

[0062] The solvent and hardener can be the same compound, but they can also be different compounds. Preferably, the solvent is the same compound as the hardener. Particularly preferred is a hardener that releases a gas during the condensation reaction, which promotes foaming.

[0063] Composition B may optionally contain water. This increases the volume of Composition B, allowing the mixing ratio with Composition A to be advantageously adjusted.

[0064] Water may also be included additionally or alternatively in composition A.

[0065] In a preferred embodiment, the combination contains at least one filler, e.g., to increase viscosity, and / or a thickener. The thickener can serve to keep the inorganic filler suspended in the solvent and / or to stabilize the filler.

[0066] In the following, the processes taking place in the mixture of composition A and composition B according to the invention are explained using the solvent / hardener carboxylic acid ester and the binder water glass.

[0067] When the main component and initiator are mixed together, the carboxylic acid ester reacts according to the following formula:

[0068] The ester removes water from the mixture, i.e., the combination (composition A + B), forming a dihydric alcohol (diol) and CO2. The removal of water shifts the polymer equilibrium of the water glass toward condensation, and the water glass hardens. Parallel to the hydrolysis of the ester, the hollow microspheres are dissolved or dissolved by the initiator, releasing the blowing agent. This causes the water glass to foam. Furthermore, the CO2 produced by the ester cleavage also foams the water glass and simultaneously acts as a hardener for the water glass. The reaction is catalyzed by the hydroxide ions in the alkaline main component.

[0069] In a preferred embodiment, the combination can comprise composition A and composition B in a ratio A:B between 100:1 and 100:30, preferably 4-20:1, particularly preferably 8-12:1, further particularly preferably 10:1 or 4:1 or 3.5:1. The ratio depends on the desired reaction time and the proportion of the carboxylic acid ester. The ratio also depends on the binder used. It also depends on which constituents are contained in composition A (apart from the hollow microspheres) and composition B (apart from the solvent). The ratio can also be reversed, i.e. A:B of 1-30:100, preferably 1:4-20, particularly preferably 1:4.

[0070] The rate of the reaction can be controlled by temperature, water addition, viscosity adjustment and pH.

[0071] The onset time of foaming can also depend on the degree of mixing. For example, mixing the two compositions at a high shear rate and using a dispersing disc can result in immediate foaming. In contrast, low shear rates and other types of agitators, such as bar or propeller agitators, can lead to delayed foaming.

[0072] In particular, the invention also provides for opening hollow microspheres by adding a solvent, thus releasing the blowing agent. This makes it possible to produce foam masses not by thermal expansion of the blowing agent-filled hollow microspheres as is usual, but also without the addition of heat, namely by destroying the capsule material (the polymer shell) and releasing the blowing agent.

[0073] Another application is the foaming of the cavities of a honeycomb panel, such as in Fig. 7. In this way, a non-combustible lightweight building panel can be produced. A lower cover layer is covered, for example, with an expanded honeycomb panel, such as those available from cardboard, aluminum, or various polymer materials. A foam according to the invention is then produced by combining and stirring the two compositions and distributed evenly in the honeycomb compartments. A second, upper cover layer can then be applied to the honeycomb support. The introduced mixture foams up, preferably after variably adjustable reaction times, and fills the cavities of the honeycomb at least partially, and preferably completely. The applied cover layer is also preferably gripped by the foam and firmly or permanently bonded to the honeycomb core.

[0074] After curing and drying, you get, for example, a lightweight board with two functional cover layers and a solid foam core, which can be provided with an appropriate edge banding after formatting.

[0075] Such non-combustible, lightweight foam panels are used, for example, as support panels for decorative elements in construction, as fillings for doors and similar wall elements. Such a door with foam filling (fire door) is, for example, Fig. 8 shown.

[0076] Another application is the foaming of a cavity between a pipe penetration and, for example, a masonry wall. In this case, a mineral foam (e.g., cement or gypsum as a binding agent) can be used. Such an application is Fig. 9 shown.

[0077] The panels or molded parts that can be produced using the combination according to the invention preferably have building material class A1 (non-combustible), A2, or B, in particular building material class A1 (the fire test can be carried out according to DIN 4102-1). The finished parts are therefore preferably non-combustible and / or additionally have a fire-retardant effect by releasing cooling water vapor. In a particularly preferred aspect of the invention, a fire retardant is therefore provided, produced using the combination or foam mass according to the invention.

[0078] Other areas of application in which the flammability of the molded parts is not important are also conceivable.

[0079] A particular advantage of the inventive combination is that, in one embodiment, it is cold-foamable, thus allowing "on-site foaming" (= in-situ foaming) from 2K cartridges (2-component system) (as is common with PU construction foam, for example), and does not require extensive equipment or equipment, e.g., for thermal foaming. Furthermore, the construction foam can, if necessary, be produced largely from inorganic, non-combustible components (for building material class A1).

[0080] In one embodiment, the two compositions A and B can be cast into any desired shape. The construction foam, especially in-situ foam, is suitable as a filling, construction, insulation, fire protection, or soundproofing foam. Particularly preferred are molded parts and lightweight panels made from the in-situ foam. Examples

[0081] The invention is explained in more detail in the following exemplary embodiments, whereby the selection of examples is not intended to limit the scope of the subject matter of the invention. The examples are intended merely to illustrate individual embodiments and advantageous effects of the invention in a model manner. 1. Production of a lightweight panel

[0082] On a laboratory scale, the main component and the initiator are mixed in a ratio of 10:1 for 20 seconds using a propeller stirrer. The mixture is then poured into a mold and sealed with a lid. After approximately ten minutes, the foamed sheet is ready for demoulding and can be removed from the mold and dried. The drying parameters can be varied depending on the size and shape of the sheet.

[0083] Lightweight panels can preferably be manufactured on an industrial scale by pumping compositions A and B into a static mixer and mixing them across its cross-section. The mixture can then be injected through a nozzle into a mold, which is then sealed.

[0084] The mixing ratio can be adjusted by the respective flow rates of the two pumps. The length of the static mixer also determines the mixing time and the degree of homogenization. After approximately ten minutes, the mold is opened, the sheets are removed from the mold, and dried. 2. Measurement of flexural strength

[0085] To determine the flexural strength (also called breaking strength) and the modulus of elasticity, tests were carried out on a Zwick testing machine of type 143 501. Sample preparation:

[0086] Lightweight panels measuring 8 cm x 10 cm x 2.5 cm were produced. For this purpose, 90 grams of composition A were mixed with 9 grams of initiator and poured into a mold. After filling, the mold was sealed with a lid and weighted down. After demolding, the panels were dried. Drying took place on a wire rack to ensure even drying on all sides.

[0087] For the tests to determine the flexural strength, samples measuring 4 cm x 2 cm x 1.5 cm (width x length x height) were sawn from these plates.

[0088] To determine the elastic modulus, samples measuring 2 cm x 8.5 cm x 1.5 cm (width x length x height) were sawn. To measure deflection, the samples needed to be longer.

[0089] A materials testing machine from the manufacturer Zwick can be used for the tensile and flexural tests. Experimental setup:

[0090] Fig. Figure 1 schematically describes the measurement setup: The sample with a width b and a height h is placed on two round supports with a distance I measured from center to center. A sensor is located centrally below the sample, which measures the deflection f of the sample. A pressure piston is located above the sample, exerting force on the center of the sample. Measurement parameters:

[0091] The pre-load value was set to 200 N. Material breakage was detected at a difference of ten [N]. The maximum force was set to 950 [N]. The feed rate was set to 2 [mm / min]. The measurement parameters used are summarized in Table 2. Table 2: Measurement parameters of the tensile testing machine. parameter Value Ballast force 200 N ΔF 10 N Fmax 950 N feed 2 mm / min 3. Influence of a fiber in composition A on the flexural strength

[0092] Composition A may optionally contain fibers. To select a suitable fiber, various mineral wool, glass, and synthetic fibers (polyacrylonitrile) were first incorporated into the combination in equal amounts (2.5 wt.%). The panels were dried according to the developed procedure, and their flexural strength was measured.

[0093] Fig. Table 2 shows the flexural strengths of the fibers used. Table 3 below lists the properties of the fibers used. The analysis shows that MiWo_1 and Glass Fiber_1 are particularly suitable for reinforcing the panels. Fibers longer than 0.25 mm increased the viscosity of the combination. This resulted in inhomogeneities in the panel, which were evident in a large scatter of the flexural tensile strengths. Table 3: Fiber types and properties used. Designation Fiber type Length [mm] Diameter [µm] MiWo_1 mineral wool 0,25 5,5 MiWo_2 mineral wool 0,50 5,5 Fiber optic_1 Glass 0,18 9-14 PAC_1 Polyacrylonitrile 0,50 27,0 PAC_2 Polyacrylonitrile 3,00 not specified Seaweed Seaweed < 3,00 not specified Fiber optic_2 Glass 3,00 20,0 4. Influence of the fiber content on the flexural strength

[0094] Two fibers (MiWo_1 and Glass Fiber_1, see Table 3) were selected. Different proportions of the total formulation were tested. For this purpose, one to four percent by weight of the fibers were added to the liquid mixture, and the flexural strength of the reinforced lightweight panels was measured in five replicates.

[0095] The measurement of the lightweight panel reinforced with MiWo_1 is in Fig. 3. The highest flexural strength is achieved at a weight fraction of three percent with a flexural strength of 1.20 ± 0.14 [N / mm 2 ] is achieved. Higher mineral wool fiber contents reduce the flexural strength, possibly because they thicken the system too much. The high standard deviation of the fivefold determination can also be explained by the thickening. The higher viscosity makes it difficult to distribute the liquid combination evenly in the mold.

[0096] The maximum bending strength of the glass fiber reinforced lightweight panel is 1.30 ± 0.19 [N / mm 2 ]. Fig. 4 describes the relationship between the glass fiber weight fraction and the resulting flexural strength.

[0097] Glass fibers and mineral wool fibers are both well suited to increasing the flexural strength of a combined product. In this example, glass fibers can achieve slightly higher flexural strength. Furthermore, in this example, glass fibers require one percent less by weight and increase the viscosity of the system less. 5. Influence of a polymer dispersion on elasticity

[0098] To reduce stiffness, a plastic dispersion can be added to the plate. To assess stiffness, the elastic modulus can be measured.

[0099] In Fig.Figure 5 shows the elastic modulus as a function of the plastic content. With increasing plastic content (in wt.%), the elastic modulus of the lightweight panel decreases. By adding up to ten wt.% plastic dispersion (relative to the total mass of the system), the elastic modulus could be increased from 294.86 ± 60.28 [N / mm 2 ] to 122.14 ± 12.42 [N / mm 2 ] can be reduced. 6. Heat conduction

[0100] To characterize the thermal conductivity of a material, the material property of thermal conductivity (λ) is used. The lower the thermal conductivity of a material, the less heat it transfers per unit time and length.

[0101] Cylindrical specimens with a diameter of 3.5 cm and a height of 2.5 cm were prepared. These were dried for two days at room temperature and then placed in a drying cabinet at 80°C for at least eight hours. The sample cylinders were then placed in an insulated device, which was Fig. 6. The front of the device was heated to approximately 600°C with a gas burner. Thermocouples were attached to the front and back to measure the temperature. The heating of the inserted sample was measured for approximately 20 minutes. It was also observed whether the samples burned or smoked.

[0102] Using samples with a known thermal conductivity (λ), a calibration curve was created to obtain the thermal conductivity of the samples. 7. Influence of fibers on thermal conductivity

[0103] The thermal conductivities of lightweight panels reinforced with mineral wool_1 and glass fiber_1 are described in Table 4. The addition of mineral wool fibers increases the thermal conductivity and consequently impairs the insulating effect. This could be due to an increase in the system viscosity. During production, foaming is slowed by the more viscous system. Due to the lower number of pores, the lightweight panel loses its insulating effect. The glass fiber_1 used does not increase the system viscosity in the amount used (wt. % = < 4%). As a result, the reinforced lightweight panel foams homogeneously, and the thermal conductivity remains unchanged compared to the unreinforced sample. Table 4: Thermal conductivity of fiber-reinforced lightweight panels. sample λ [W / m*K] Not reinforced 0,09 1% MiWo_1 0,17 4% MiWo_2 0,16 1%Fiber Optic_1 0,09 4% fiberglass_2 0,10 8. Influence of a polymer dispersion on thermal conductivity

[0104] The influence of four to eight wt.% plastic dispersion on the thermal conductivity of a lightweight panel is shown in Table 5. It was found that the thermal conductivity increases with the plastic content. Table 5: Thermal conductivity of different plastic components. sample λ [W / m*K] Not reinforced 0,09 4% plastic 0,10 6% plastic 0,16 8% plastic 0,25 9. Fire test

[0105] A fire test was conducted according to DIN 4102-1. This test serves to classify the building material class and simulates a fire. The target was Class A1 (non-combustible) for a panel reinforced with glass fiber_1. A lightweight panel reinforced with two percent glass fiber_1 by weight was tested, as this is particularly advantageous in this example due to its mechanical properties and low thermal conductivity.

[0106] Several samples, each 4 cm long and 4 cm wide, were sawn out. They were then stacked on top of each other and sawn to a height of 5 cm. DIN 4102-1 requires a five-fold determination. Therefore, five of these samples were prepared, dried at 105°C for 6 hours, and then dried in a desiccator over CaCl2. The "sample sandwich" was placed in a grid frame.

[0107] The furnace was preheated to 750°C. The sample was then suspended within five seconds. A propane gas flame was positioned above the furnace opening. To check for the formation of flammable gases during the test, the flame was observed to determine whether any flames developed in the furnace. A mirror was also used to monitor the formation of flames in the furnace. The sample was left in the furnace until the furnace temperature exceeded its maximum. The loss on ignition in height and weight, the maximum furnace temperature, and the flame expansion were recorded.

[0108] Table 6 shows the evaluation of the five samples. The lightweight panel reinforced with glass fiber_1 passed the fire test for construction class A1 according to DIN 4102-1. No flames formed inside the furnace. The propane gas flame above the furnace opening did not increase in size. It was extinguished by the water vapor from the panel and could only be reignited after five minutes. The panels lost an average of 1 cm in height and 15.68% ± 0.26% of their weight. In addition, the calorific value of the panel was determined using a bomb calorimeter. After three measurements, this value was 2054.3 ± 41.2 [J / g]. Table 6: Evaluation of the fire test of the lightweight panel reinforced with glass fiber 1. sample Duration [min.] ΔT [K] Loss on ignition [%] Shrinkage [cm] Flame ignited [min.] A 90 61 15,41% 1,00 0 B 30 14 15,61% 1,00 0 C 30 19 15,42% 1,10 0 D 30 22 15,90% 0,90 0 E 30 23 16,06% 1,00 0 10. Example recipe of the combination

[0109] The following ranges of components of composition A and composition B are listed as examples: Composition A raw material Percentage by weight water glass 40-60% Water 0-10% KOH 0-5% Defoamers 0-0,5% filler 10-40% Hollow microspheres 1-5% Other additives (fibers, plastic dispersion) 0-4%

[0110] The water glass is, for example, sodium or potassium silicate with a solids content of 25 to 55%, for example, sodium water glass 37 / 40. Inorganic minerals are preferred as fillers. Other components can be glass or mineral wool fibers with an average fiber length of approximately 50 µm to approximately 500 µm. Furthermore, a plastic dispersion can be added to improve elasticity and water resistance. Composition B raw material Percentage by weight Solvent / Hardener 20-80% filler 0-60% Thickener 0-10%

[0111] In this example, the solvent and hardener are the same compound, for example, 1,3-dioxolan-2-one or 4-methyl-1,3-dioxolan-2-one. Depending on the desired reaction time and the proportion of the carboxylic acid ester in composition B, a favorable foam is obtained by a mixing ratio A:B of approximately 1-20:1, preferably 8-12:1, particularly preferably 9-11:1, and particularly preferably 10:1.

[0112] In a particularly preferred embodiment, the following proportions are used: Composition A raw material Percentage by weight water glass 40-60% Water 4-8% KOH 2-4% Defoamers 0,02-0,08% filler 20-40% Hollow microspheres 1-5% Other additives (fibers, plastic dispersion) 1-4%

[0113] In this example, the water glass is also sodium or potassium silicate with a solids content of 25 to 55%, for example, sodium water glass 37 / 40. Inorganic minerals are preferred as fillers. Other components can be glass or mineral wool fibers with an average fiber length of approximately 50 µm to approximately 500 µm. Furthermore, a plastic dispersion can be added to improve elasticity and water resistance. Composition B raw material Percentage by weight Solvent / Hardener 20-80% filler 15-40% Thickener 4-10%

[0114] In this example, the solvent and hardener are the same compound, for example, 1,3-dioxolan-2-one or 4-methyl-1,3-dioxolan-2-one. In this preferred embodiment, Composition A is mixed with Composition B in a ratio of 10:1.

[0115] An example recipe for the combination with a plastic dispersion as a binder is: Composition A [wt.%] Composition B [wt.%] 25-80% plastic dispersion 5-50% organic carbonates 2-20% bullets with propellant gas 5-40% cement or quicklime 0-60% filler (preferably inorganic)

[0116] In a special embodiment, the recipe is: Composition A [wt.%] Composition B [wt.%] 60% plastic dispersion 40% 4-methyl-1,3-dioxolan-2-one 6.5% bullets with propellant gas 60% Portland cement (CEM I) 33.5% filler (preferably inorganic)

[0117] The compositions can be mixed, for example, in an A:B ratio of 4:1. This produces an elastic foam with a calorific value of approximately 20,831 J / g.

[0118] Examples of recipes for combination with cement (e.g. portand cement; CEM I) as a binder are: Composition A [wt.%] Composition B [wt.%] 20-40% cement 10-30% water 2-10% setting accelerator (e.g., e.g., Rapid 800) 1-15% 1,3-dioxolan-2-one 0.8-1.5% Expancel 031DU40 Composition A [wt.%] Composition B [wt.%] 10-30% water 20-40% cement 0.8-1.5%Expancel 031DU40 2-10% setting accelerator 10-30% 4-Methyl-1,3-dioxolan-2-one 0.5-5% inorganic thickener (e.g. layered silicates)

[0119] In a special embodiment, the recipe is, for example: Composition A [wt.%] Composition B [wt.%] 35% cement 15% water 3% setting accelerator (e.g. SikaRapid 800) 5% 1,3-dioxolan-2-one 1.2% Expancel 031DU40

[0120] The foaming ratio can be, for example, 1:4. Composition A [wt.%] Composition B [wt.%] 15% water 35% cement 1% Expancel 031DU40 3% setting accelerator 20% 4-methyl-1,3-dioxolan-2-one 1% inorganic thickener (e.g. layered silicates)

[0121] The foaming ratio can be, for example, 3.5:1.

[0122] A cement foam produced according to these recipes has a calorific value of approximately 1600 J / g. The foam therefore falls into building material class A1 (non-combustible).

[0123] Examples of recipes for combination with gypsum as a binder are: Composition A [wt.%] Composition B [wt.%] 20-40% gypsum (e.g. Rotband) 10-30% water 0.8-1.5% Expancel 031DU40 1-15% 1,3-dioxolan-2-one Composition A [wt.%] Composition B [wt.%] 10-30% water 20-40% gypsum (e.g. Rotband) 0.8-1.5% Expancel 031DU40 10-30% 4-Methyl-1,3-dioxolan-2-one 0.5-5% . Inorganic thickener (e.g. phyllosilicates)

[0124] In a special embodiment, the recipe is, for example: Composition A [wt.%] Composition B [wt.%] 20% gypsum (e.g. Rotband) 12% water 1% Expancel 031DU40 7% 1,3-dioxolan-2-one

[0125] The foaming ratio can be, for example, 1:4. Composition A [wt.%] Composition B [wt.%] 10% water 20% gypsum (e.g. Rotband) 1% Expancel 031DU40 5% 4-methyl-1,3-dioxolan-2-one 1% inorganic thickener (e.g. layered silicates)

[0126] The foaming ratio can be, for example, 4:1.

[0127] Gypsum foam produced according to these recipes has a calorific value of approximately 441 J / g. The foam therefore falls into building material class A1 (non-combustible). Character description Fig.1: Scheme of measuring flexural strength Fig. 2: Bending strength of fiber-reinforced lightweight panels Fig. 3: Flexural strengths of different weight percentages of MiWo_1 Fig. 4: Flexural strengths of different weight percentages of glass fiber_1 Fig. 5: Dependence of the elastic modulus on the plastic content Fig. 6: Schematic structure of heat conduction Fig. 7: Foam filling in honeycomb panel Fig. 8: Door with foam filling (fire door) Fig. 9: Mineral foam in the cavity between a pipe penetration and a brickwork QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 3095312 A

[0003] US 3850650 A

[0003] US 6497945 B1

[0003] US 8,822,557 B2

[0004] DE 101 41 777 A1

[0005] DE 32 44 523 A1

[0006] Cited non-patent literature

[0000] KSW Sing (1985). Pure and Applied Chemistry, 57(4): pp. 603-619

[0047]

Claims

[1] Combination comprising a composition A and a composition B, wherein the composition A contains hollow microspheres and the composition B contains a solvent for opening these hollow microspheres and the composition A and / or the composition B contains an inorganic and / or organic binder, the hollow microspheres having a polymer shell and containing a propellant, the combination being in a 2-component cartridge. [2] Combination according to claim 1 comprising a composition A and a composition B, wherein the composition A contains an inorganic and / or organic binder and hollow microspheres and the composition B contains a solvent for opening these hollow microspheres, wherein the hollow microspheres have a polymer shell and contain a blowing agent. [3] The combination according to claim 1 or 2, wherein composition B contains a hardener for hardening or crosslinking the inorganic and / or organic binder. [4] The combination according to any one of the preceding claims, wherein the inorganic and / or organic binder is selected from the following group: polyolefins, vinyl polymers, styrene-butadiene copolymers (preferably styrene-butadiene-acrylate), polyacrylates, drying oils, natural resins, alkyd resins, epoxy esters, polyesters, alkali silicates, phenolic resins, urea resins, melamine resins, reaction resins, SBR latices, natural latex, neoprene latex, acrylic resins or combinations thereof; and is preferably an alkali silicate, particularly preferably sodium silicate or potassium silicate. [5] The combination according to any one of the preceding claims, wherein the inorganic and / or organic binder is a plastic and is present as a dispersion. [6] The combination according to any one of the preceding claims, wherein the polymer shell is selected from the following group: EVA (ethylene-vinyl acetate copolymer); polyvinylidene chloride and / or acrylonitrile; acrylonitrile, methyl methacrylate and / or methacrylonitrile; or combinations thereof; and preferably comprises acrylonitrile and / or methacrylonitrile, most preferably acrylonitrile and methacrylonitrile. [7] The combination according to any one of the preceding claims, wherein the propellant is selected from the following group: liquefied gases comprising short-chain hydrocarbons selected from propane, butane, isobutane, pentane, isopentane or combinations thereof; dimethyl ether, air, CO2, nitrogen, CFCs or combinations thereof. [8] The combination according to any one of the preceding claims, wherein the solvent is selected from the following group: acetone, nitromethane, dimethyl sulfoxide, organic carboxylic acid esters R 1 -OC(=O)-OR 2 with R1 ,R 2 = alkyl, allyl and / or aryl radicals; or combinations thereof; preferably a carboxylic acid ester. [9] The combination according to any one of claims 3 to 8, wherein the solvent and the curing agent are the same compound. [10] The combination according to claim 8 or 9, wherein the carboxylic acid ester is selected from the following group: dimethoxyformic anhydride, 1,3-dioxolan-2-one, 4-methyl-1,3-dioxolan-2-one, 4-hydroxymethyl-1,3-dioxolan-2-one or combinations thereof; and preferably 1,3-dioxolan-2-one or 4-methyl-1,3-dioxolan-2-one or a combination thereof.

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