Lightweight cement-bonded composite core bodies, prefabricated sandwich panels with these core bodies and wall systems formed from them.

Abstract

Lightweight cement-bound composite core body that can be incorporated as a core layer in a structural element, the core body comprising lightweight particle elements dispersed in a cement-bound matrix, wherein the cement-bound matrix contains at least one inorganic binder, at least one polymeric modifier and at least one fibrous reinforcing component, and wherein the core body further comprises at least one secondary mineral component derived from an industrial by-product and / or a recycled mineral source, wherein the core body has a dry density of less than 500 kg / m³ in the cured state. 3 and has a compressive strength of at least 3 MPa.

Description

Technical field

[0001] The present utility model relates to building materials and prefabricated building elements, in particular to lightweight cement-bonded composite core bodies containing lightweight particles and reinforcements, to prefabricated sandwich panels containing such core bodies between inorganic facing layers, and to wall systems composed of a multitude of such panels, wherein the materials and structures are configured to offer a combination of low density, useful compressive strength, thermal insulation, sound insulation and fire resistance, while at the same time enabling sustainable construction through the inclusion of industrial mineral by-products. BACKGROUND OF THE INVENTION

[0002] Lightweight cementitious materials, where attempts are made to use lightweight polymer particles such as expanded polystyrene, are often limited by poor adhesion between the particles and the cementitious matrix, segregation or floating of low-density particles during molding, brittle fracture under stress, shrinkage-related cracking during curing and drying, and moisture sensitivity, which can impair mechanical properties and insulation performance. Sandwich panels with polymer foam cores often face challenges regarding fire behavior and regulatory restrictions, while mineral cores can be heavy and brittle. Therefore, there is an engineering need for a lightweight cementitious composite core body that can be integrated into a prefabricated sandwich panel architecture with inorganic face sheets.so that the resulting panel and wall system achieves low weight, robust durability, improved thermal properties, and high fire resistance and sound insulation ratings using materials that are commercially available on a large scale. SUMMARY OF THE INVENTION

[0003] According to the present utility model, a lightweight cement-bound composite core body is provided, configured for integration as a core layer into a structural element, wherein the core body comprises lightweight particle elements distributed in a cement-bound matrix such that the lightweight particle elements provide density reduction and thermal insulation, while the cement-bound matrix ensures load-bearing continuity, and wherein the cement-bound matrix comprises at least one inorganic binder, at least one polymeric modifier, and at least one fibrous reinforcing component, and wherein the core body further comprises at least one secondary mineral component derived from an industrial by-product and / or a recycled mineral source, and wherein the core body is configured to have a dry density of less than 500 kg / m³ in the cured state. 3and has a compressive strength of at least 3 MPa, and in preferred but not limiting embodiments, the core body is further configured to have a thermal conductivity of no more than 0.19 W / m·K and a moisture content of no more than 8% under standardized conditioning conditions.

[0004] In non-restrictive embodiments, the light particle elements comprise polymeric expanded, foamed, hollow and / or cellular particles enclosing expanded polystyrene (EPS) beads, and the light particle elements may alternatively or additionally comprise expanded polymer beads, recycled polymer foam granules, hollow microspheres or functional equivalents that can remain stable in a cement-bound matrix, and the light particle elements may have an average particle size in the range of 1.0 to 6.0 mm and preferably 2.0 to 4.0 mm, and the light particle elements may be present in a range of 30 to 65 wt.% of the total dry matter of the core body and preferably 40 to 55 wt.% of the total dry matter, it being noted that these ranges are exemplary and that other fill quantities may be selected to adjust the balance between density, strength and insulation.

[0005] In further, non-limiting embodiments, the inorganic binder comprises ordinary Portland cement and / or mixed cement and / or calcium sulfoaluminate cement and / or alkali-activated binder and / or geopolymer binder, and the inorganic binder may be present in an amount of 20 to 45 wt.% of the total dry matter of the core body and preferably 25 to 35 wt.% of the total dry matter, maintaining the targets for cured density and compressive strength, and in further, non-limiting embodiments, the cement-bound matrix may additionally comprise fillers and / or additional cement-bound components that do not substantially impair the desired low density and strength.

[0006] In further, non-limiting embodiments, the polymeric modifier comprises a latex, an aqueous dispersion and / or a redispersible polymer powder, and the polymeric modifier may comprise at least one polymer selected from styrene-butadiene rubber (SBR), vinyl acetate-ethylene (VAE), ethylene-vinyl acetate (EVA), acrylic polymers, polyurethane polymers and combinations thereof, and the polymeric modifier may be present in an amount of 0.5 to 2.5 wt.% of the total dry matter of the core body and preferably 1.0 to 1.8 wt.% of the total dry matter, wherein the polymeric modifier is selected and dosed such that the cohesion, interfacial adhesion, toughness, water resistance and crack resistance of the cured core body are increased compared to an otherwise comparable unmodified cement-bound matrix.

[0007] In further non-restrictive embodiments, the fibrous reinforcing component comprises cellulose fibers and / or one or more fibers selected from glass fibers, basalt fibers, polymer fibers, carbon fibers and natural fibers, and the fibrous reinforcing component may be present in an amount of 0.1 to 1.0 wt.% of the total dry matter of the core body and preferably 0.3 to 0.6 wt.% of the total dry matter, wherein the fibrous reinforcing component is configured to inhibit shrinkage cracks and provide microcrack bridging so that mechanical integrity is maintained at low density.

[0008] In further, non-restrictive embodiments, the secondary mineral component comprises one or more materials selected from fly ash, phosphogypsum, slag, expanded clay derivative, ceramic-like light mineral particles, ceramic aggregates and functional equivalents thereof, and the secondary mineral component may be present in an amount of 0 to 10 wt.% of the total dry matter of the core body and preferably 5 to 8 wt.% of the total dry matter, wherein the secondary mineral component is selected to make at least one contribution to sustainability through by-product utilization, durability, dimensional stability, fire behavior and / or mechanical performance, while simultaneously achieving the goal of low density.

[0009] In preferred, but not limiting, embodiments, the core body comprises lightweight particle elements, each having a surface finish selected from polymer-coated, cement-coated, mineral-coated, roughened, and combinations thereof, such that the cured core body includes a region around the particle elements that is enriched with polymer and / or fine mineral binder compared to a bulk matrix, thereby promoting bonding between particles and matrix and reducing bead pull-out and segregation effects in the cured structure, while maintaining the desired density and strength.

[0010] In preferred, but not limiting, embodiments, the core body is configured as a flat plate core with a thickness of 20 to 300 mm, the thickness being selected based on the desired thermal and acoustic performance as well as handling requirements, while maintaining the defined curing density and compressive strength.

[0011] According to further aspects of the utility model, a prefabricated sandwich panel is also provided, comprising a first outer facing layer, a second outer facing layer, and a core layer arranged between the first and second outer facing layers, wherein the core layer comprises the lightweight cement-bonded composite core body described herein, and wherein each outer facing layer may comprise an inorganic board selected from calcium silicate boards, fiber cement boards, cement-bonded boards, magnesium oxide boards, gypsum boards, and functional equivalents, and wherein each outer facing layer may have a thickness of 2 to 12 mm and preferably 4 to 6 mm, the prefabricated sandwich panel being configured to provide an advantageous combination of low density, stiffness,It offers durability and fire behavior in conjunction with inorganic cover layers while retaining the insulation advantages associated with the lightweight composite core.

[0012] In preferred, but not limiting, embodiments, the prefabricated sandwich panel comprises an interface bonding zone between the core layer and at least one outer face layer, wherein the interface bonding zone comprises an adhesive zone, a polymer cement zone, a cement-bonded slurry zone, a porous infiltration zone, a mechanical interlocking zone, or any combination thereof, and the prefabricated sandwich panel comprises at least one edge with a profile consisting of tongue-and-groove, step rebate, dovetail, interlocking, labyrinth, snap, wedge, and multi-chamber profiles to facilitate assembly and alignment in a wall construction, and the panel may have an overall thickness of 80 to 200 mm and, due to the low density of the core layer, be configured for manual handling and installation without heavy lifting equipment.

[0013] In preferred, but not limiting, embodiments, the prefabricated sandwich panel is configured to have a thermal conductivity of no more than 0.19 W / m·K, and the prefabricated sandwich panel is further configured to have an airborne sound insulation of at least 50 dB at a panel thickness of about 125 mm, it being noted that the performance values ​​may vary depending on the thickness, choice of face sheet and connection details, while remaining within the scope of the disclosed architectures and compositions.

[0014] According to further aspects of the utility model, a wall system is also provided comprising a plurality of prefabricated sandwich panels arranged side by side to form a non-load-bearing wall structure, wherein the wall system comprises a connection interface between adjacent panels, which includes at least one connection profile, a connecting element, a fastening receptacle, a dowel receptacle, and a gasket receptacle, and wherein the wall system may further comprise at least one connecting element selected from metal dowels, screws, anchors, clamps, rails, brackets, and combinations thereof, and wherein the wall system is configured as an internal partition, external facade wall, perimeter wall, or modular wall unit, and wherein the wall system is configured to have a sound insulation class (STC) of at least 48 and preferably at least 52, and is configured tothat it has a thermal transmittance (U-value) of no more than 0.25 W / m, 2 ·K, and wherein the wall system is configured to provide a fire resistance of at least 4 hours when assembled with inorganic external facings and connection details compatible with this fire resistance class.

[0015] In preferred embodiments, the lightweight cement-bonded composite core body, the prefabricated sandwich panel and the wall system are asbestos-free and preferably also formaldehyde-free, thereby supporting compliance with legal regulations and consideration of indoor air quality without restricting the disclosure of the compositions, structures and performance objectives. Detailed description of preferred embodiments

[0016] According to the present utility model, a lightweight cement-bonded composite core body is provided, containing lightweight particulate elements, including but not limited to EPS beads, in a cement-bonded matrix comprising an inorganic binder, a polymeric modifier, and fiber reinforcement. The core body further contains at least one secondary mineral component derived from an industrial by-product and / or a recycled mineral source, wherein the cured core body is configured to have a dry density of less than 500 kg / m³. 3and achieves a compressive strength of at least 3 MPa, and is optionally configured to achieve a thermal conductivity of 0.19 W / m·K or less and a moisture content of 8% or less, and a prefabricated sandwich panel is further provided in which the core body is arranged between opposing inorganic facing sheets, such as calcium silicate boards, and a wall system is further provided comprising a plurality of such panels arranged and connected to each other to form a non-load-bearing wall structure. 1. Definitions and functional architecture

[0017] In the present disclosure, the term “lightweight cementitious composite core body” refers to a cured, dimensionally stable cementitious composite configured as a panel core and incorporating lightweight particle elements dispersed in a cementitious matrix, such that the particle elements contribute to density reduction and thermal insulation, while the matrix provides compressive strength and fire resistance; the term “polymeric modifier” refers to polymer additives compatible with cementitious systems that enhance cohesion, adhesion, water resistance, and toughness, making EPS-containing cementitious composites virtually durable and non-brittle; and the term “fibrous reinforcing component” refers to fibers that prevent microcracks and improve tensile and flexural strength by bridging cracks and stabilizing shrinkage.and the term "secondary mineral constituents" refers to industrial by-products and / or recycled minerals that can function as fillers, pozzolan additives, sulfate additives, density modifiers and / or shelf-life enhancers. 2. Lightweight particulate elements (EPS and alternatives)

[0018] The lightweight particle elements preferably comprise expanded polystyrene beads, which are commercially available in various bead sizes and densities suitable for composite materials, and in certain embodiments the EPS beads comprise a nominal diameter of 2.0 mm to 4.0 mm to achieve uniform distribution and stable mechanical properties, although other sizes between 1.0 mm and 6.0 mm may also be used depending on the desired density and insulation level, and in further embodiments the lightweight particle elements additionally or alternatively comprise expanded polypropylene beads, recycled polymer foam granules, hollow polymer microspheres, hollow ceramic particles or combinations thereof, provided that the particles remain stable in a cementitious environment and can be distributed in the matrix in such a way as to prevent segregation.

[0019] To improve the adhesion between particles and matrix, the lightweight particle elements can be selected and / or provided with surfaces that are wettable with cement-bound slurries and polymer-modified binders. For example, the particle elements can be supplied or treated as coated particles, including polymer-coated particles and / or particles coated with cement-bound slurry. The resulting core body can therefore include an interfacial region around the particle elements characterized by the presence of polymer and improved adhesion, which improves compressive strength and reduces bead pull-out under load. Although such a conditioning condition can be achieved in practice through known site or factory techniques, the utility model protection relates to the resulting product structures rather than a manufacturing process. 3. Inorganic binder (cement-bound matrix)

[0020] The inorganic binder can comprise ordinary Portland cement (OPC) as the primary binder, and OPC can include commercially available cement grades such as CEM I class cement, including common construction grades used in dry mixes, and in further embodiments the binder can comprise blended cement systems, cement-bound materials, calcium sulfoaluminate cement, alkali-activated binders and geopolymer binders, with such alternative binder systems being used to tailor early strength, shrinkage behavior, durability and sustainability, and the binder being selected such that the matrix cures to a cohesive mineral phase surrounding the light particle elements and interacting with the polymeric modifier and fibers. 4. Polymeric Modifying Agent (commercial examples)

[0021] The polymeric modifier can be provided as latex powder (redispersible polymer powder) and / or as liquid latex, and the polymeric modifier can include SBR polymers, VAE polymers, EVA polymers, acrylic polymers, polyurethane dispersions and mixtures thereof, and commercially available examples that can be used in non-restrictive embodiments include SBR latex additives marketed under the SikaLatex label. ® -family sold including SikaLatex ® SBR products, described as cement-based binders and mortar additives, and redispersible polymer powders, which fall under the WACKER VINNAPAS range. ® -types are sold, including VINNAPAS ®5044 N, which is described as a dispersible polymer powder for drywall mortars, as well as alternatives with renewable ingredients such as VINNECO ® 5044 N, which can also be used if a sustainability label is desired.

[0022] The content of polymeric modifier can be selected in certain embodiments within ranges such as 0.5% to 2% of the dry mix to balance toughness and processability while meeting density and strength targets, and the polymeric modifier improves cohesion and adhesion so that the EPS phase does not behave as inert, detachable inclusions, but as a mechanically integrated lightweight phase. 5. Fiber reinforcement (commercial examples)

[0023] The fibrous reinforcing component may include cellulose fibers, which are particularly useful in cementitious composites for microcrack control and improving mix cohesion, and are among the commercially available cellulose fiber additives that include cellulose fibers, such as ARBOCEL. ® -Cellulose fibers used in construction chemical products which, according to the description, improve processability and prevent microcracks, and the fibers can be selected with typical lengths ranging from less than one millimeter to several millimeters, depending on the desired crack bridging behavior and the molding process used by the manufacturer.

[0024] In further embodiments, the fibrous reinforcing component can include glass fibers, basalt fibers, polypropylene fibers, PVA fibers, carbon fibers and natural fibers or mixtures thereof, and the fiber content can be selected, for example, within 0.1% to 1.0% of the dry matter to reinforce the matrix and suppress shrinkage cracks while maintaining processability and low density. 6. Secondary mineral components (by-products and recycled minerals)

[0025] The secondary mineral component may include industrial by-products such as fly ash and phosphogypsum, as well as slags, including steel slag and / or blast furnace slag, and may further include ceramicite and expanded clay derivatives and ceramic aggregates, and the secondary mineral component may, for example, be present within 0% to 10% of the dry mix and preferably within 5% to 8% to improve sustainability and adjust durability, fire behavior and dimensional stability without significantly affecting the desired density and strength of the core body, and the selection and dosage of the secondary mineral component is carried out by a specialist taking into account local availability and the desired performance indicators. 7. Product performance goals and testability

[0026] The lightweight cement-bonded composite core is configured so that, after curing under conditions typical in the cement construction industry and after reaching practical maturity, the dry density is below 500 kg / m³. 3 where the compressive strength is at least 3 MPa, and in preferred embodiments the cured core body further exhibits a thermal conductivity of at most 0.19 W / m·K and a moisture content of at most 8%, those skilled in the art will understand that such parameters can be routinely used with established laboratory methods and can be achieved by selecting the EPS bead fraction, the binder fraction, the polymer fraction, the fiber fraction and the secondary mineral fraction within the ranges of the disclosure while maintaining homogeneity and adequate matrix continuity. 8. Prefabricated sandwich panel construction (examples of commercial facing layers)

[0027] A prefabricated sandwich panel according to the present utility model comprises a first outer layer and a second outer layer, which are inorganic boards, and in preferred embodiments the inorganic boards are calcium silicate boards with a thickness between 4 mm and 6 mm, although thicknesses between 2 mm and 12 mm may also be used depending on the fire resistance class and handling requirements, and in non-restrictive, commercially available examples the face sheets may be made from calcium silicate board families such as Skamol SKAMOTEC. ® / SkamoDoor ® Calcium silicate boards, which are described as lightweight and non-combustible, should be selected, and comparable calcium silicate and fiber cement boards available at hardware stores can also be used.

[0028] The core layer of the panel consists of the lightweight cement-bonded composite core body described herein, and the panel may include an interfacial bonding zone between the core and at least one cover layer, wherein the bonding zone may be designed as an adhesive zone, polymer-cement transition zone, cement-bonded slurry zone, a porous infiltration zone, a mechanical locking zone or combinations thereof, and the interfacial bonding zone may be enhanced by selecting a cover layer panel with surface roughness, porosity, perforation or texturing that allows for physical anchoring and infiltration.

[0029] In preferred embodiments, the panel is configured to achieve a thermal conductivity of 0.19 W / m·K or less and an airborne sound insulation of at least 50 dB at a total thickness of approximately 125 mm, and the panel is further configured for manual installation without heavy lifting equipment, thus enabling quick on-site installation and reduced complexity of work processes. 9. Wall system (product arrangement features without process claim)

[0030] A wall system is provided, comprising a plurality of prefabricated sandwich panels arranged side by side to form a non-load-bearing wall structure. The wall system can be configured such that the panels can be joined using adhesives, mechanical fasteners, dowel rods, and / or interlocking panel edge profiles. While the specific joining process depends on the implementation, the protected subject matter is the wall system as a product arrangement comprising the plurality of panels. In preferred embodiments, the wall system is configured to achieve a U-value of 0.25 W / m²K. 2·K or less and offers an STC of at least 48 and preferably at least 52, while maintaining a high fire resistance, for example on the order of several hours, in combination with suitable inorganic covering layers and connection details. Work examples

[0031] The following examples serve as non-restrictive compositions and product designs that a person with average technical knowledge can reproduce using commercially available components, and the listed trade names serve only as examples of suitable materials, with equivalent products being acceptable. Example 1: Core body formulation with a target value of <500 kg / m³ 3 and ≥3 MPa

[0032] A lightweight cement-bonded composite core body was produced using EPS beads with a nominal diameter of 2 to 4 mm, ordinary Portland cement as the primary binder, a polymer modifier which is either an SBR latex additive such as a SikaLatex-type product. ® SBR or as a redispersible VAE polymer powder such as VINNAPAS ® 5044 N was selected, as well as cellulose fibers, which are known as ARBOCEL ® -Cellulose fibers were selected and produced, and fly ash was used as a secondary mineral component.

[0033] For a batch of 100 kg dry matter, the dry formulation was determined as follows: EPS beads 50.0 kg, OPC 30.0 kg, fly ash 6.0 kg, ARBOCEL cellulose fibers 0.5 kg, polymer modifier (solid-based) 1.5 kg and mineral filler and / or additional binder fraction 12.0 kg, and water in an amount sufficient to achieve a processable consistency for forming a core body, taking into account that the required water content depends on the bead fraction, fiber quality and filler fineness.

[0034] After curing to the maturity typical for cement-bound composites, the cured core body exhibited a dry density in the range of approximately 410 to 480 kg / m³. 3 and a compressive strength in the range of approximately 3.2 to 4.2 MPa, and in many versions the thermal conductivity was within approximately 0.16 to 0.19 W / m · K, thus fulfilling the utility model objectives. Example 2: Alternative core body using phosphogypsum and slag

[0035] A second lightweight cement-bonded composite core body was produced, in which the secondary mineral component consisted of phosphogypsum and slag, while the lightweight particle elements remained EPS beads and the binder remained OPC, and a redispersible polymer powder of the VAE type, such as VINNAPAS, was used as the polymer modifier. ® 5044 N was selected, and cellulose fibers such as ARBOCEL were chosen as fibers.

[0036] For a batch of 100 kg dry matter, the dry formulation was determined as follows: EPS beads 45.0 kg, OPC 32.0 kg, phosphogypsum 5.0 kg, slag 3.0 kg, cellulose fibers 0.5 kg, polymer modifier (solid-based) 1.2 kg and mineral filler and / or additional binder fraction 13.3 kg, as well as water, were provided as required for the formation of the core body.

[0037] After hardening to maturity, the hardened core body typically exhibited a dry density of approximately 420 to 490 kg / m³. 3 and a compressive strength of typically about 3.0 to 3.8 MPa, and the moisture content under standardized conditioning conditions was ≤ 8% in preferred embodiments. Example 3: Prefabricated sandwich panel using calcium silicate facing sheets

[0038] A prefabricated sandwich panel was produced in which the core layer comprised the cured core body of Example 1 or Example 2, and the outer layers consisted of 5 mm thick calcium silicate boards from commercially available calcium silicate board families such as SKAMOTEC. ® / SkamoDoor ®or equivalent products were selected, and the total thickness of the panel was chosen to be in the range of 115 to 130 mm, and an interface bonding zone was provided between the core layer and each cover layer by selecting a cover layer panel surface that promotes infiltration and interlocking, and / or by providing an adhesive or polymer cement transition zone.

[0039] The resulting panel, with a thickness of approximately 125 mm, achieved an airborne sound insulation of at least 50 dB in typical applications, and the thermal conductivity of the panel was at or below 0.19 W / m·K in preferred applications, and due to the low density of the core body in combination with thin inorganic facings, the panel was configured for manual handling and installation. Example 4: Wall system comprising several panels

[0040] A wall system was designed as a product arrangement comprising a plurality of panels according to Example 3, arranged side by side to form a non-load-bearing wall structure, the product configuration being designed for connection by adhesive and / or mechanical features, including the optional use of polymer-modified cementitious adhesives and optional dowel elements such as galvanized steel dowels, and the wall system being configured to achieve a thermal transmittance of U ≤ 0.25 W / m²K 2 ·K and a sound insulation of STC ≥ 48 and preferably STC ≥ 52 when implemented with suitable connection and sealing details. Notes on trade names

[0041] All trade names mentioned here (including SikaLatex) ® , VINNAPAS ® , ARBOCEL ® and SKAMOTEC ® / SkamoDoor ®) serve only as non-restrictive examples of commercially available materials that can meet the described functional requirements, and equivalent products from other suppliers may be used without affecting the scope of the claims.

Claims

[1] A lightweight cement-bound composite core body that can be incorporated as a core layer in a building element, the core body comprising lightweight particle elements dispersed in a cement-bound matrix, the cement-bound matrix containing at least one inorganic binder, at least one polymeric modifier and at least one fibrous reinforcing component, and the core body further comprising at least one secondary mineral component derived from an industrial by-product and / or a recycled mineral source, the core body having a dry density of less than 500 kg / m³ in the cured state. 3 and has a compressive strength of at least 3 MPa. [2] Lightweight cement-bonded composite core body according to claim 1, wherein the lightweight particle elements comprise polymeric expanded, foamed, hollow and / or cellular particles and comprise expanded polystyrene (EPS) beads. [3] Lightweight cement-bonded composite core body according to claim 1 or 2, wherein the lightweight particle elements have an average particle size of 1.0 to 6.0 mm. [4] Lightweight cement-bonded composite core body according to claim 3, wherein the average particle size is 2.0 to 4.0 mm. [5] Lightweight cement-bound composite core body according to any one of claims 1 to 4, wherein the light particle elements are present in an amount of 30 to 65 wt.%, based on the total dry matter of the core body. [6] Lightweight cement-bonded composite core body according to claim 5, wherein the light particle elements are present in an amount of 40 to 55 wt.%, based on the total dry matter of the core body. [7] Lightweight cement-bound composite core body according to any one of claims 1 to 6, wherein the inorganic binder comprises ordinary Portland cement and / or mixed cement and / or calcium sulfoaluminate cement and / or alkali-activated binder and / or geopolymer binder. [8] Lightweight cement-bonded composite core body according to any one of claims 1 to 7, wherein the inorganic binder is present in an amount of 20 to 45 wt.%, based on the total dry matter of the core body. [9] Lightweight cement-bonded composite core body according to claim 8, wherein the inorganic binder is present in an amount of 25 to 35 wt.%, based on the total dry matter of the core body. [10] Lightweight cement-bonded composite core body according to any one of claims 1 to 9, wherein the polymeric modifying agent comprises a latex, an aqueous dispersion and / or a redispersible polymer powder. [11] Lightweight cement-bonded composite core body according to any one of claims 1 to 10, wherein the polymeric modifier comprises at least one polymer selected from styrene-butadiene rubber (SBR), vinyl acetate-ethylene (VAE), ethylene-vinyl acetate (EVA), acrylic polymers, polyurethane polymers and combinations thereof. [12] Lightweight cement-bonded composite core body according to any one of claims 1 to 11, wherein the polymeric modifying agent is present in an amount of 0.5 to 2.5 wt.%, based on the total dry matter of the core body. [13] Lightweight cement-bonded composite core body according to claim 12, wherein the polymeric modifier is present in an amount of 1.0 to 1.8 wt.%, based on the total dry matter of the core body. [14] Lightweight cement-bonded composite core body according to any one of claims 1 to 13, wherein the fibrous reinforcing component comprises cellulose fibers and / or one or more fibers selected from glass fibers, basalt fibers, polymer fibers, carbon fibers and natural fibers. [15] Lightweight cement-bonded composite core body according to any one of claims 1 to 14, wherein the fibrous reinforcing component is present in an amount of 0.1 to 1.0 wt.%, based on the total dry matter of the core body. [16] Lightweight cement-bonded composite core body according to claim 15, wherein the fibrous reinforcing component is present in an amount of 0.3 to 0.6 wt.%, based on the total dry matter of the core body. [17] Lightweight cement-bound composite core body according to any one of claims 1 to 16, wherein the secondary mineral component comprises one or more materials selected from fly ash, phosphogypsum, slag, expanded clay derivative, ceramic-like lightweight mineral particles, ceramic aggregates and functional equivalents thereof. [18] Lightweight cement-bonded composite core body according to any one of claims 1 to 17, wherein the secondary mineral component is present in an amount of 0 to 10 wt.%, based on the total dry matter of the core body. [19] Lightweight cement-bonded composite core body according to claim 18, wherein the secondary mineral component is present in an amount of 5 to 8 wt.%, based on the total dry matter of the core body. [20] Lightweight cement-bound composite core body according to any one of claims 1 to 19, wherein the core body comprises lightweight particle elements, each having a surface finish selected from polymer-coated, cement-coated, mineral-coated, roughened and combinations thereof, such that the core body encloses a region around the particle elements which is enriched compared to a bulk matrix with polymer and / or fine mineral binder. [21] Lightweight cement-bonded composite core body according to any one of claims 1 to 20, wherein the cured core body has a thermal conductivity of ≤ 0.19 W / m·K. [22] Lightweight cement-bonded composite core body according to any one of claims 1 to 21, wherein the cured core body has a moisture content of ≤ 8% under standardized conditioning conditions. [23] Lightweight cement-bonded composite core body according to any one of claims 1 to 22, wherein the core body is designed as a flat plate core with a thickness of 20 to 300 mm. [24] Prefabricated sandwich panel comprising a first outer face layer, a second outer face layer and a core layer arranged between the first and the second outer face layer, wherein the core layer comprises the lightweight cement-bonded composite core body according to any one of claims 1 to 23. [25] Prefabricated sandwich panel according to claim 24, wherein each outer face layer comprises an inorganic board selected from calcium silicate boards, fiber cement boards, cement-bonded boards, magnesium oxide boards, gypsum boards and functional equivalents. [26] Prefabricated sandwich panel according to claim 24 or 25, wherein each outer face layer has a thickness of 2 to 12 mm. [27] Prefabricated sandwich panel according to claim 26, wherein each outer face layer has a thickness of 4 to 6 mm. [28] Prefabricated sandwich panel according to any one of claims 24 to 27, wherein the panel comprises an interfacial bonding zone between the core layer and at least one outer cover layer, the interfacial bonding zone comprising an adhesive zone, a polymer cement zone, a cement-bonded slurry zone, a porous infiltration zone, a mechanical locking zone or any combination thereof. [29] Prefabricated sandwich panel according to any one of claims 24 to 28, wherein at least one edge of the panel comprises a profile selected from tongue and groove, step rebate, dovetail, interlocking, labyrinth, snap, wedge and multi-chamber profiles. [30] Prefabricated sandwich panel according to any one of claims 24 to 29, wherein the panel has a total thickness of 80 to 200 mm. [31] Prefabricated sandwich panel according to one of claims 24 to 30, wherein the panel is configured for manual handling and installation without heavy lifting equipment due to the low density of the core layer. [32] Prefabricated sandwich panel according to any one of claims 24 to 31, wherein the panel is configured to have a thermal conductivity of ≤ 0.19 W / m·K. [33] Prefabricated sandwich panel according to one of claims 24 to 32, wherein the panel is configured to provide an airborne sound insulation of at least 50 dB at a panel thickness of about 125 mm. [34] Wall system comprising a plurality of prefabricated sandwich building panels according to any one of claims 24 to 33, arranged side by side to form a non-load-bearing wall structure. [35] Wall system according to claim 34, wherein the wall system comprises a connection interface between adjacent panels, comprising at least one connection profile, one connecting element, one fastening receiving device, one dowel receiving device and one sealing receiving groove. [36] Wall system according to claim 34 or 35, wherein the wall system comprises at least one connecting element selected from metal dowels, screws, anchors, clamps, rails, brackets and combinations thereof. [37] Wall system according to any one of claims 34 to 36, wherein the wall system is configured as an internal partition wall, external facade wall, perimeter wall or modular wall unit. [38] Wall system according to any one of claims 34 to 37, wherein the wall system is configured to have a sound insulation class (STC) of at least 48. [39] Wall system according to claim 38, wherein the wall system is configured to have a sound insulation class (STC) of at least 52. [40] Wall system according to one of claims 34 to 39, wherein the wall system is configured to have a thermal transmittance (U-value) of ≤ 0.25 W / m² 2 ·K exhibits. [41] Wall system according to any one of claims 34 to 40, wherein the wall system is configured to have a fire resistance of at least 4 hours when assembled with the inorganic facing layers and connection details that are compatible with this fire resistance class. [42] Lightweight cement-bonded composite core body according to any one of claims 1 to 23, the prefabricated sandwich panel according to any one of claims 24 to 33 or the wall system according to any one of claims 34 to 41, wherein the materials are asbestos-free. [43] Lightweight cement-bonded composite core body, prefabricated sandwich panel or wall system according to claim 42, wherein the materials are formaldehyde-free.