Polyurethane thermal insulation flame-retardant soundproofing material and preparation method thereof

Abstract

The application discloses a polyurethane heat-insulating flame-retardant sound-insulating material and a preparation method thereof. The material comprises the following raw materials: combined polyol, polymethylene polyphenyl polyisocyanate, sunflower stem pith micro-powder, defatted rice bran micro-powder, cuttlebone porous micro-powder, foaming agent, foam stabilizer and catalyst; wherein, according to weight parts, the combined polyol is 100 parts, the polymethylene polyphenyl polyisocyanate is 105-120 parts, the sunflower stem pith micro-powder is 2-5 parts, the defatted rice bran micro-powder is 5-12 parts, and the cuttlebone porous micro-powder is 3-8 parts; wherein, the cuttlebone porous micro-powder has a layer-columnar three-dimensional interconnected pore structure. The application realizes high-value utilization of agricultural, forestry and marine wastes by complementation and synergistic effect of the three kinds of natural biological solid waste fillers, simultaneously improves the flame-retardant and sound-insulating performance while retaining excellent heat-insulating performance, and enhances the mechanical strength of the material.

Description

Technical Field

[0001] This invention relates to the field of polyurethane foam materials technology, and in particular to a polyurethane thermal insulation, flame retardant and sound insulation material and its preparation method. Background Technology

[0002] Polyurethane foam is lightweight, has low thermal conductivity, and excellent thermal insulation properties, making it widely used in building energy conservation, cold chain logistics, and pipeline insulation. However, polyurethane foam is a flammable polymer material that burns rapidly when heated or exposed to fire, releasing large amounts of toxic fumes and posing significant fire safety hazards. Furthermore, its lightweight, porous structure limits its ability to dissipate sound waves, resulting in poor sound insulation and noise reduction performance. Therefore, polyurethane foam alone cannot simultaneously meet the comprehensive needs of the building and industrial sectors for thermal insulation, flame retardancy, and sound insulation.

[0003] To improve the flame retardant and sound insulation properties of polyurethane foam, flame retardants or functional fillers are usually introduced into the system. On the one hand, commonly used halogenated and phosphorus-based synthetic flame retardants have problems such as releasing toxic gases during combustion, poor compatibility with the matrix, easy migration and precipitation, and heavy environmental burden. On the other hand, high-density inorganic fillers introduced to improve sound insulation performance often increase the material density and thermal conductivity, impairing the material's thermal insulation performance. This creates a trade-off between thermal insulation, flame retardancy, and sound insulation, making it difficult to achieve both simultaneously.

[0004] The background description is provided for the purpose of understanding the relevant technologies in this field and is not intended as an admission of prior art. Summary of the Invention

[0005] To address the aforementioned issues, this invention aims to provide a polyurethane thermal insulation, flame retardant, and sound insulation material and its preparation method. This material uses multi-source natural biological solid waste as a functional filler, which, while maintaining the excellent thermal insulation performance of polyurethane foam, endows the material with good flame retardant and sound insulation properties, and realizes the high-value utilization of agricultural, forestry, and marine biological solid waste.

[0006] In a first aspect, embodiments of the present invention provide a polyurethane thermal insulation, flame retardant, and sound insulation material, comprising the following raw materials: a combination of polyols, polymethylene polyphenyl polyisocyanates, sunflower stem pith powder, defatted rice bran powder, cuttlebone porous powder, a foaming agent, a foam stabilizer, and a catalyst; wherein, by weight, the combination of polyols comprises 100 parts, polymethylene polyphenyl polyisocyanates comprises 105-120 parts, sunflower stem pith powder comprises 2-5 parts, defatted rice bran powder comprises 5-12 parts, and cuttlebone porous powder comprises 3-8 parts; wherein the cuttlebone porous powder has a layer-column three-dimensional interconnected pore structure.

[0007] Optionally, the porous cuttlebone powder has a mesh size of 200-400 mesh; and the porous cuttlebone powder contains more than or equal to 85% calcium carbonate by weight.

[0008] Optionally, the defatted rice bran powder has a mesh size of 200-400; and by weight, the defatted rice bran powder contains 10%-15% phytic acid, 15%-20% rice bran protein and 40%-50% cellulose.

[0009] Optionally, the sunflower stem pith powder has a mesh size of 100-200 mesh and a bulk density of 0.02-0.05 g / cm³; based on the weight of the sunflower stem pith powder, the sunflower stem pith powder contains greater than or equal to 40% cellulose and 15%-25% lignin.

[0010] Optionally, the combined polyol is a mixture of polyether polyol and bio-based polyol in a weight ratio of 3:1 to 5:1.

[0011] Optionally, the bio-based polyol is selected from at least one of castor oil-based polyol, epoxidized soybean oil-based polyol, and rosin ester polyol.

[0012] Optionally, by weight, the foaming agent is 3-6 parts, the foam stabilizer is 1.5-3 parts, and the catalyst is 0.5-1.5 parts, wherein the foaming agent is selected from at least one of cyclopentane and water, the foam stabilizer is an organosilicon foam stabilizer, and the catalyst is selected from at least one of amine catalysts and tin catalysts.

[0013] Optionally, the foaming agent is a compound system composed of cyclopentane and deionized water in a weight ratio of 3:1; the foam stabilizer is a polyether-modified organosilicon foam stabilizer; and the catalyst is an amine-tin composite catalytic system composed of triethylenediamine and dibutyltin dilaurate in a weight ratio of 2:1.

[0014] Optionally, the polyol, sunflower stem pith powder, defatted rice bran powder, cuttlebone porous powder, foaming agent, foam stabilizer and catalyst are used as component A, and the polymethylene polyphenyl polyisocyanate is used as component B, wherein the weight ratio of component A to component B is 0.9:1 to 1.3:1.

[0015] In a second aspect, the present invention provides a polyurethane thermal insulation, flame retardant and sound insulation material, comprising a polyurethane matrix and sunflower stem pith micro powder, defatted rice bran micro powder and cuttlebone porous micro powder dispersed in the polyurethane matrix; the sunflower stem pith micro powder is 0.8%~2.5% by weight of the finished product, the defatted rice bran micro powder is 2.0%~6.0% and the cuttlebone porous micro powder is 1.0%~4.0%; wherein the cuttlebone porous micro powder has a layer-column three-dimensional interconnected pore structure.

[0016] In a third aspect, embodiments of the present invention also provide a method for preparing the polyurethane thermal insulation, flame retardant, and sound insulation material according to any of the above embodiments of the present invention, comprising the following steps:

[0017] S1. After washing, drying, pulverizing and sieving sunflower stem pith, defatted rice bran and cuttlebone respectively, sunflower stem pith micro powder, defatted rice bran micro powder and cuttlebone porous micro powder are obtained respectively. The particle size of the cuttlebone is controlled to retain its layer-column three-dimensional interconnected pore structure.

[0018] S2. Weigh the combined polyol, sunflower stem pith powder, defatted rice bran powder, cuttlebone porous powder, foaming agent, foam stabilizer and catalyst according to the weight parts, mix and stir until uniformly dispersed to obtain component A;

[0019] S3. Using polymethylene polyphenyl polyisocyanate as component B, add component B to component A, stir and pour into a mold to allow it to foam freely;

[0020] S4. After curing, demolding and maintenance, the polyurethane thermal insulation, flame retardant and sound insulation material is obtained.

[0021] In this embodiment of the invention, three types of multi-source natural biological solid waste—sunflower stem pith powder, defatted rice bran powder, and cuttlebone porous powder—are introduced into the polyurethane foam system as functional fillers. Through the complementary functions and compatible performance of the three fillers, the material simultaneously possesses excellent comprehensive performance in terms of heat preservation, flame retardancy, and sound insulation, while also improving its mechanical strength.

[0022] Among them, sunflower stem pith micro powder is an important component contributing to heat preservation: with its natural tetrahedral closed-cell structure and extremely low packing density, it can increase the tortuous path of solid phase heat conduction when dispersed in the polyurethane foam wall. At the same time, its own closed-cell structure can help block the gas convection heat transfer inside the foam. Even after the introduction of functional fillers, it can still maintain the material's low thermal conductivity.

[0023] Defatted rice bran micro powder is an important contributing component for flame retardancy: by utilizing its naturally abundant phytic acid (phosphorus source), rice bran protein (nitrogen source) and cellulose (carbon source), an intrinsic phosphorus-nitrogen-carbon intumescent flame retardant system is constructed in situ. During combustion, it promotes the formation of a dense intumescent char layer, blocks the transfer of heat and oxygen, and significantly improves the flame retardant performance of the material.

[0024] Porous cuttlebone micropowder is a key component contributing to sound insulation while also synergistically enhancing flame retardant performance. Its unique natural layer-column three-dimensional interconnected pore structure causes multiple scattering of incident sound waves, interfacial dissipation, and impedance mismatch, significantly improving the material's sound insulation and noise reduction performance. The micropowder is controlled within a particle size range of 200-400 mesh, dissecting only the macroscopic overall structure of the cuttlebone while retaining the original porous framework within each individual micropowder particle. Under high-temperature combustion conditions, the calcium carbonate in the micropowder decomposes, absorbing heat and releasing carbon dioxide to dilute combustible smoke. Its high-temperature decomposition products can also react in situ with phosphorus-containing active components released from defatted rice bran decomposition to form a calcium phosphate ceramic phase, filling the pore defects of the expanded char layer, improving the density and thermal stability of the char layer, and synergistically enhancing the flame retardant and smoke-suppressing effects.

[0025] Testing revealed that the thermal conductivity of the polyurethane thermal insulation, flame retardant, and sound insulation material prepared by this invention can be maintained at 0.022~0.026 W / (m·K), comparable to pure polyurethane foam without added functional fillers, and its thermal insulation performance is not significantly degraded by the introduction of functional fillers. Its compressive strength can reach 345 kPa, significantly improved compared to pure polyurethane foam. In terms of flame retardancy, the material's continuous burning time can be reduced to 0 seconds, furnace temperature rise is significantly reduced, and combustion residue rate is greatly improved. Regarding sound insulation, the material's sound insulation can reach 32 dB, significantly higher than pure polyurethane foam. Furthermore, this invention fully utilizes agricultural, forestry, and marine biological solid waste, achieving high-value utilization of waste materials and providing a polyurethane material with excellent comprehensive performance for the field of building energy conservation and safety protection.

[0026] Other optional features and technical effects of the embodiments of the present invention are partly described below and partly apparent from reading this document. Attached Figure Description

[0027] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The elements shown are not limited to the scale shown in the drawings, and the same or similar reference numerals in the drawings denote the same or similar elements, wherein:

[0028] Figure 1 This is a photograph of a polyurethane thermal insulation, flame retardant, and sound insulation material sample prepared according to an embodiment of the present invention. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings. Here, the illustrative embodiments and descriptions of this invention are used to explain the invention, but are not intended to limit the invention. Where there is no conflict, the technical features of the various embodiments of this invention can be combined with each other. Unless otherwise stated, all parts in this document are parts by weight, and percentages involving component content are based on the weight of the corresponding component or material.

[0030] This invention provides a polyurethane thermal insulation, flame retardant and sound insulation material, the raw materials of which include a combination of polyols, polymethylene polyphenyl polyisocyanates, sunflower stem pith powder, defatted rice bran powder, cuttlebone porous powder, foaming agent, foam stabilizer and catalyst. Figure 1 This is a photograph of a polyurethane thermal insulation, flame retardant, and sound insulation material sample prepared according to an embodiment of the present invention.

[0031] In some embodiments, the combined polyol is composed of a polyether polyol and a bio-based polyol mixed in a weight ratio of 3:1 to 5:1; for example, a weight ratio of 3:1, 3.5:1, 4:1, 4.5:1, or 5:1. In some embodiments, the polyether polyol has a hydroxyl value of 350 to 450 mg KOH / g (e.g., 350, 400, or 450 mg KOH / g) and a viscosity at 25°C of 3000 to 5000 mPa·s (e.g., 3000, 4000, or 5000 mPa·s). In some embodiments, the bio-based polyol is selected from at least one of castor oil-based polyol, epoxidized soybean oil-based polyol, and rosin ester polyol, with a hydroxyl value of 180-280 mgKOH / g (e.g., 180, 230, or 280 mgKOH / g) and a viscosity at 25°C of 500-2000 mPa·s (e.g., 500, 1000, 1500, or 2000 mPa·s). Introducing bio-based polyols helps to increase the bio-based content of the material, further realizing its green utilization.

[0032] In some embodiments, materials other than polymethylene polyphenyl polyisocyanate are used as component A, and polymethylene polyphenyl polyisocyanate is used as component B, with the isocyanate group weight percentage being 30% to 32% (e.g., 30%, 31%, or 32%) and the viscosity at 25°C being 150 to 250 mPa·s (e.g., 150, 200, or 250 mPa·s). In some embodiments, the amount of polymethylene polyphenyl polyisocyanate used is 105 to 120 parts by weight (e.g., 100, 105, 110, 115, or 120 parts); in other embodiments, the amount of polymethylene polyphenyl polyisocyanate used is 105 to 120 parts by weight.

[0033] In some embodiments, the sunflower stem pith powder is derived from the pith of sunflower stalks, possessing a natural tetrahedral closed-cell structure and extremely low bulk density. In some embodiments, the sunflower stem pith powder has a mesh size of 100-200 mesh (e.g., 100, 150, or 200 mesh) and a bulk density of 0.02-0.05 g / cm³. 3 (e.g., 0.02, 0.03, 0.04, or 0.05 g / cm³) 3The sunflower stem pith powder, by weight, contains greater than or equal to 40% cellulose (e.g., 40%, 45%, or 50%) and 15% to 25% lignin (e.g., 15%, 20%, or 25%). In some embodiments, the amount of sunflower stem pith powder is 2 to 5 parts by weight (e.g., 2, 2.5, 3, 3.5, 4, 4.5, or 5 parts). Sunflower stem pith powder possesses a natural tetrahedral closed-cell structure. When dispersed in a foam matrix, it increases the path length for heat conduction while reducing convective heat transfer within the cells, helping to maintain excellent thermal insulation performance of the material while introducing functional fillers.

[0034] In some embodiments, the defatted rice bran powder is powder obtained by defatting rice bran, a byproduct of rice processing. In some embodiments, the defatted rice bran powder has a mesh size of 200-400 mesh (e.g., 200, 300, or 400 mesh) and a moisture content of less than or equal to 3% (e.g., 1%, 2%, or 3%); by weight, the defatted rice bran powder contains 10%-15% phytic acid (e.g., 10%, 12%, or 15%), 15%-20% rice bran protein (e.g., 15%, 18%, or 20%), and 40%-50% cellulose (e.g., 40%, 45%, or 50%). In some embodiments, the defatted rice bran powder is used in an amount of 5-12 parts by weight (e.g., 5, 6, 8, 10, or 12 parts). The phytic acid, rice bran protein and cellulose naturally abundant in defatted rice bran powder can serve as phosphorus, nitrogen and carbon sources, respectively. When heated and burned, they form an intrinsically expanding flame-retardant phosphorus-nitrogen-carbon system, promoting the formation of a dense char layer. At the same time, defatted rice bran powder dispersed in the polyurethane foam walls also plays an interfacial reinforcing role.

[0035] In some embodiments, the porous cuttlebone powder is derived from the inner shell of the cuttlefish, which naturally possesses a layer-column three-dimensional interconnected pore structure. In this embodiment of the invention, the layer-column three-dimensional interconnected pore structure is a hierarchical porous skeletal structure naturally present in the inner shell of the cuttlebone. It is composed of calcareous lamellae (also known as septa) arranged in an orderly stacked manner along the thickness direction of the cuttlebone, and columnar support structures vertically connected between adjacent lamellae. Adjacent lamellae and the surrounding columnar support enclose an independent chamber, and the columnar support is evenly distributed within the chamber and supports the lamellae to maintain a fixed spacing. The chambers are interconnected in three-dimensional space through the gaps between the edges of the lamellae and the columnar support, forming a hierarchical interconnected pore network from large chambers to micro-gap.

[0036] In this embodiment of the invention, three types of multi-source natural biological solid waste—sunflower stem pith powder, defatted rice bran powder, and cuttlebone porous powder—are introduced into the polyurethane foam system as functional fillers. Through the complementary functions and compatible performance of the three fillers, the material simultaneously possesses excellent comprehensive performance in terms of heat preservation, flame retardancy, and sound insulation, while also improving its mechanical strength.

[0037] In some implementations, sunflower stem pith powder can be used as an important component contributing to heat preservation. As an explanation, sunflower stem pith powder has a natural tetrahedral closed-cell structure and extremely low bulk density. When dispersed in the polyurethane foam wall, it can increase the tortuous path of solid-phase heat conduction. At the same time, its own closed-cell structure can help block the gas convection heat transfer inside the foam. Even after the introduction of functional fillers, the material can still maintain a low thermal conductivity.

[0038] In some embodiments, defatted rice bran powder can be used as an important contributing component for flame retardancy. For explanation, defatted rice bran powder utilizes its naturally abundant phytic acid (phosphorus source), rice bran protein (nitrogen source), and cellulose (carbon source) to construct an intrinsically expanding flame retardant system of phosphorus-nitrogen-carbon in situ. During combustion, it promotes the formation of a dense expanding char layer, blocks the transfer of heat and oxygen, and significantly improves the flame retardant performance of the material.

[0039] In some possible solutions, cuttlebone powder may be introduced into the polyurethane system as an inorganic flame retardant filler, but such solutions typically involve ultra-fine grinding of cuttlebone into submicron-sized amorphous powder.

[0040] This kind of ultrafine grinding often makes it difficult to preserve the natural porous structure of cuttlebone during the powdering process. As a result, the flame-retardant effect of its calcium carbonate component decomposing when heated is mainly utilized, and the potential acoustic noise reduction value brought by its natural porous structure is not explored.

[0041] In contrast, the cuttlebone porous micro powder of the present invention is a powder that completely retains the above-mentioned original layer-column three-dimensional interconnected pore structure. During the preparation process, by controlling the crushing method and particle size, only the macroscopic overall structure of the cuttlebone is disassembled, without destroying the pore skeleton inside each micro powder particle.

[0042] As an explanation, cuttlebone porous micro powder is an important component contributing to sound insulation, and at the same time can synergistically improve flame retardant performance: with its unique natural layer-column three-dimensional interconnected pore structure, it forms multiple scattering, interface dissipation and impedance mismatch of incident sound waves, thereby significantly improving the sound insulation and noise reduction performance of the material.

[0043] The micro powder is controlled within a particle size range of 200-400 mesh, disassembling only the macroscopic overall structure of cuttlebone, while the original porous skeleton is still completely preserved inside each micro powder particle. Under high-temperature combustion scenarios, the calcium carbonate in the micro powder can decompose and absorb heat, releasing carbon dioxide to dilute combustible smoke. Its high-temperature decomposition products can also react in situ with the phosphorus-containing active components released from the decomposition of defatted rice bran to generate a calcium phosphate ceramic phase, filling the pore defects of the expanded carbon layer, improving the density and thermal stability of the carbon layer, and synergistically enhancing the flame retardant and smoke-suppressing effect.

[0044] Optionally, the volumetric porosity of the layer-column three-dimensional interconnected porous structure is not less than 80% (e.g., 80%, 85%, or 90%), the spacing between adjacent layers is 50-600 μm (e.g., 50, 100, 300, or 600 μm), the thickness of a single layer is 1-5 μm, and the diameter of the columnar support is 2-8 μm. These microstructural features can be directly observed and characterized using a scanning electron microscope (SEM), and are structural parameters that can be routinely verified by those skilled in the art. In some embodiments, the mesh size of the cuttlebone porous powder is 200-400 mesh (e.g., 200, 250, 300, 350, or 400 mesh); the calcium carbonate content, based on the weight of the cuttlebone porous powder, is greater than or equal to 85% (e.g., 85%, 88%, 90%, 92%, or 95%). In some embodiments, the amount of the cuttlebone porous powder used is 3-8 parts by weight (e.g., 3, 4, 5, 6, or 8 parts). In some embodiments, to maintain the layer-column three-dimensional interconnected pore structure of the porous cuttlebone powder, the particle size of the cuttlebone can be controlled during the preparation process (e.g., controlled to 200-400 mesh) to preserve its layer-column three-dimensional interconnected pore structure and avoid damage to its pore structure due to excessive grinding. By way of explanation and not limitation, the layer-column three-dimensional interconnected pore structure can generate multiple scattering and impedance mismatch of sound waves, thereby improving the sound insulation performance of the material.

[0045] In some embodiments, the foaming agent is selected from at least one of cyclopentane and water; the foam stabilizer is an organosilicon foam stabilizer; and the catalyst is selected from at least one of amine catalysts and tin catalysts.

[0046] In some embodiments, the foaming agent is 3 to 6 parts by weight (e.g., 3, 4, 5 or 6 parts), the foam stabilizer is 1.5 to 3 parts by weight (e.g., 1.5, 2, 2.5 or 3 parts), and the catalyst is 0.5 to 1.5 parts by weight (e.g., 0.5, 1, 1.2 or 1.5 parts).

[0047] In some embodiments, the combined polyol, sunflower stem pith powder, defatted rice bran powder, cuttlebone porous powder, foaming agent, foam stabilizer and catalyst are used as component A, and the polymethylene polyphenyl polyisocyanate is used as component B. The weight ratio of component A to component B is 0.9:1 to 1.3:1 (e.g. 1:1, 1:1.05, 1:1.10, 1:1.15 or 1:1.20).

[0048] In some embodiments, based on the total mass of the polyurethane thermal insulation, flame retardant, and sound insulation material, the material comprises a polyurethane matrix and sunflower stem pith powder, defatted rice bran powder, and cuttlebone porous powder dispersed in the polyurethane matrix, wherein the sunflower stem pith powder comprises 0.8% to 2.5% (e.g., 0.8%, 1.5%, or 2.5%), the defatted rice bran powder comprises 2.0% to 6.0% (e.g., 2.0%, 4.0%, or 6.0%), and the cuttlebone porous powder comprises 1.0% to 4.0% (e.g., 1.0%, 2.5%, or 4.0%). Optionally, the polyurethane matrix formed by reacting the combined polyol with the polymethylene polyphenyl polyisocyanate comprises 85.0% to 92.0% (e.g., 85.0%, 88.0%, or 92.0%); optionally, the sum of the weight percentages of the above components is 100%. In some embodiments, the sunflower stem pith powder, defatted rice bran powder, and cuttlebone porous powder are dispersed in the cell walls of the polyurethane matrix.

[0049] In some embodiments, the polyurethane thermal insulation, flame retardant, and sound-insulating material is rigid polyurethane foam. In some embodiments, the thermal conductivity of the material is less than or equal to 0.026 W / (m·K) (e.g., 0.022, 0.023, 0.024, 0.025, or 0.026 W / (m·K)). In some embodiments, the compressive strength of the material is greater than or equal to 268 kPa (e.g., 268, 285, 300, 320, or 345 kPa). In some embodiments, the sound insulation of the material is greater than or equal to 20 dB (e.g., 20, 22, 25, 27, 30, or 32 dB).

[0050] This invention introduces three types of biological solid waste fillers with different natural structures and compositions into a polyurethane foam system, enabling the material to achieve comprehensive performance in terms of heat preservation, flame retardancy, and sound insulation.

[0051] As an explanation rather than a limitation, in terms of thermal insulation performance, sunflower stem pith micropowder has a natural tetrahedral closed-cell structure and extremely low bulk density. It is dispersed in the polyurethane foam cell walls, which on the one hand extends the heat conduction path inside the material, and on the other hand helps to maintain a high closed-cell ratio of the foam, so that the material still maintains a low thermal conductivity after the introduction of functional fillers.

[0052] In an interpretive rather than restrictive sense, regarding flame retardant properties, the three fillers work synergistically from multiple dimensions, including catalytic char formation, cooling and dilution, and char layer reinforcement, to jointly improve the flame retardant and smoke suppression properties of the material:

[0053] The phytic acid, rice bran protein and cellulose naturally contained in defatted rice bran powder together constitute the phosphorus-nitrogen-carbon intrinsic intumescent flame retardant system. When heated, it catalyzes the dehydration of the matrix into carbon, forming an intumescent carbon layer skeleton that isolates heat and oxygen transfer.

[0054] The calcium carbonate in the porous micro powder of cuttlebone decomposes at high temperature, absorbing heat and releasing carbon dioxide, which lowers the system temperature and dilutes the combustible flue gas. At the same time, the high-temperature decomposition products of calcium carbonate and the phosphorus-containing active components produced by the decomposition of phytic acid can react in situ in the high-temperature combustion field to generate a calcium phosphate ceramic phase, which fills the micropores and defects of the expanded carbon layer, improves the mechanical strength, thermal stability and barrier properties of the carbon layer, further prevents heat and oxygen from penetrating into the matrix, and inhibits the release of combustible flue gas.

[0055] The porous carbon skeleton formed after the combustion of sunflower stem pith powder can serve as a carbonization carrier, helping to improve the continuity and structural stability of the carbon layer.

[0056] As an explanation and not a limitation, regarding sound insulation performance, the unique layer-column three-dimensional interconnected pore structure of cuttlebone porous micropowder constructs a large number of acoustic dissipation interfaces within the material, where sound waves undergo multiple scattering and impedance mismatch, thereby significantly improving the sound insulation and noise reduction performance of the material; cuttlebone porous micropowder is the main contributor to the sound insulation performance of the material of this invention.

[0057] It should be noted that the source, mesh size, composition, and other parameters of the functional fillers described in this invention can be selected and adjusted within the conventional range in the art. The specific numerical ranges and preferred solutions listed are merely examples and should not be construed as limiting the scope of protection of this invention.

[0058] In other embodiments, the present invention also provides a polyurethane foam material, such as a polyurethane foam sound insulation material, comprising a polyurethane foam matrix and cuttlebone porous micropowder dispersed in the polyurethane foam matrix, the cuttlebone porous micropowder having a layer-column three-dimensional interconnected pore structure. Optionally, the polyurethane foam is a rigid polyurethane foam. Optionally, the sound insulation of the material is greater than or equal to 20 dB. Optionally, the mesh size of the cuttlebone porous micropowder is 200-400 mesh. In some embodiments, the polyurethane foam sound insulation material further comprises sunflower stem pith micropowder to further impart thermal insulation properties to the material, thereby constituting a polyurethane foam thermal insulation and sound insulation material. In some embodiments, the polyurethane foam sound insulation material further comprises defatted rice bran micropowder to further impart flame retardant properties to the material, thereby constituting a polyurethane foam sound insulation and flame retardant material. In some embodiments, the polyurethane foam sound insulation material also comprises sunflower stem pith micropowder and defatted rice bran micropowder, thereby constituting a polyurethane thermal insulation, flame retardant, and sound insulation material with combined thermal insulation, flame retardant, and sound insulation properties. Those skilled in the art will understand that the solutions provided in the other embodiments can be combined in a suitable manner with any other suitable embodiments / executives or features thereof herein to obtain new embodiments, which fall within the scope of the invention.

[0059] Based on the above components, parameters and mechanisms of action, the following further lists various technical solutions of the present invention and their preferred ranges and specific values. The ranges, preferred sub-ranges and specific values ​​can be used individually or in combination to limit the present invention. Any combination thereof is part of the content disclosed in the present invention. The specific values ​​listed are only examples and do not constitute a limitation on the scope of protection of the present invention.

[0060] In some embodiments, the polyurethane thermal insulation, flame retardant, and sound insulation material comprises the following raw materials: a combination of polyols, polymethylene polyphenyl polyisocyanates, sunflower stem pith powder, defatted rice bran powder, cuttlebone porous powder, a foaming agent, a foam stabilizer, and a catalyst; wherein, by weight, the combination of polyols is 100 parts, polymethylene polyphenyl polyisocyanates are 100-130 parts, sunflower stem pith powder is 2-5 parts, defatted rice bran powder is 5-12 parts, and cuttlebone porous powder is 3-8 parts.

[0061] In some embodiments, the polymethylene polyphenyl polyisocyanate is 100-130 parts, preferably 105-120 parts; for example, 100 parts, 105 parts, 110 parts, 115 parts, 120 parts, 125 parts or 130 parts.

[0062] In some embodiments, the sunflower stem pith powder is 2 to 5 parts, preferably 2 to 3 parts or 3 to 5 parts; for example, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts or 5 parts.

[0063] In some embodiments, the defatted rice bran powder is 5 to 12 parts, preferably 5 to 8 parts or 8 to 12 parts; for example, 5 parts, 6 parts, 8 parts, 10 parts or 12 parts.

[0064] In some embodiments, the porous cuttlebone powder is 3 to 8 parts, preferably 3 to 5 parts or 5 to 8 parts; for example, 3 parts, 4 parts, 5 parts, 6 parts or 8 parts.

[0065] In some embodiments, the foaming agent is 3 to 6 parts, preferably 4 to 6 parts; for example, 3 parts, 4 parts, 5 parts, or 6 parts. The foam stabilizer is 1.5 to 3 parts, preferably 2 to 3 parts; for example, 1.5 parts, 2 parts, 2.5 parts, or 3 parts. The catalyst is 0.5 to 1.5 parts, preferably 1 to 1.5 parts; for example, 0.5 parts, 1 part, 1.2 parts, or 1.5 parts.

[0066] In some embodiments, the porous cuttlebone powder has a mesh size of 200-400 mesh, preferably 250-350 mesh; for example, 200 mesh, 250 mesh, 300 mesh, 350 mesh, or 400 mesh. The calcium carbonate content of the porous cuttlebone powder, by weight, is greater than or equal to 85%, preferably greater than or equal to 90%; for example, 85%, 88%, 90%, 92%, or 95%. In some embodiments, the porous cuttlebone powder has a layer-column three-dimensional interconnected pore structure, with a porosity (volume fraction) of not less than 80%, and a spacing of 50-600 μm between adjacent layers.

[0067] In some embodiments, the defatted rice bran powder has a mesh size of 200-400 mesh, preferably 250-350 mesh; for example, 200 mesh, 300 mesh, or 400 mesh. By weight, the defatted rice bran powder contains 10%-15% phytic acid (e.g., 10%, 12%, or 15%), 15%-20% rice bran protein (e.g., 15%, 18%, or 20%), and 40%-50% cellulose (e.g., 40%, 45%, or 50%). In some embodiments, the defatted rice bran powder has a moisture content of less than or equal to 3%, preferably less than or equal to 2%; for example, 1%, 2%, or 3%.

[0068] In some embodiments, the sunflower stem pith powder has a mesh size of 100-200 mesh; for example, 100 mesh, 150 mesh, or 200 mesh. In some embodiments, the bulk density of the sunflower stem pith powder is 0.02-0.05 g / cm³. 3 For example, 0.02 g / cm³ 3 0.03g / cm 3 0.04g / cm 3 Or 0.05g / cm 3 The sunflower stem pith powder contains, by weight, 40% or more cellulose (e.g., 40%, 45% or 50%) and 15% to 25% lignin (e.g., 15%, 20% or 25%).

[0069] In some embodiments, the combined polyol is composed of a polyether polyol and a bio-based polyol mixed in a weight ratio of 3:1 to 5:1, preferably 3:1 to 4:1; for example, a weight ratio of 3:1, 3.5:1, 4:1, 4.5:1, or 5:1. In some embodiments, the polyether polyol has a hydroxyl value of 350 to 450 mg KOH / g (e.g., 350, 400, or 450 mg KOH / g) and a viscosity at 25°C of 3000 to 5000 mPa·s (e.g., 3000, 4000, or 5000 mPa·s). In some embodiments, the bio-based polyol is selected from at least one of castor oil-based polyol, epoxidized soybean oil-based polyol, and rosin ester polyol, having a hydroxyl value of 180-280 mgKOH / g (e.g., 180, 230, or 280 mgKOH / g) and a viscosity of 500-2000 mPa·s at 25°C (e.g., 500, 1000, 1500, or 2000 mPa·s).

[0070] In some embodiments, the polymethylene polyphenyl polyisocyanate has an isocyanate group content of 30% to 32% by weight (e.g., 30%, 31% or 32%) and a viscosity of 150 to 250 mPa·s at 25°C (e.g., 150, 200 or 250 mPa·s).

[0071] In some embodiments, the foaming agent is selected from at least one of cyclopentane and water; the foam stabilizer is an organosilicon foam stabilizer; and the catalyst is selected from at least one of amine catalysts and tin catalysts.

[0072] In some embodiments, the foaming agent is a compound system of cyclopentane and deionized water in a weight ratio of 3:1; the foam stabilizer is a polyether-modified silicone foam stabilizer; and the catalyst is an amine-tin composite catalytic system of triethylenediamine and dibutyltin dilaurate in a weight ratio of 2:1.

[0073] In some embodiments, the combined polyol, sunflower stem pith powder, defatted rice bran powder, cuttlebone porous powder, foaming agent, foam stabilizer, and catalyst are used as component A, and the polymethylene polyphenyl polyisocyanate is used as component B. The weight ratio of component A to component B is 0.9:1 to 1.3:1; for example, 1:1, 1:1.05, 1:1.10, 1:1.15, or 1:1.20.

[0074] In some embodiments, the polyurethane thermal insulation, flame retardant, and sound insulation material is rigid polyurethane foam. In some embodiments, the sunflower stem pith powder, defatted rice bran powder, and cuttlebone porous powder are dispersed in the foam walls of the polyurethane matrix; the layer-column three-dimensional interconnected pore structure of the cuttlebone porous powder causes multiple scattering and impedance mismatch of sound waves.

[0075] In some embodiments, the thermal conductivity of the material is less than or equal to 0.026 W / (m·K), preferably less than or equal to 0.024 W / (m·K); for example, 0.022, 0.023, 0.024, 0.025 or 0.026 W / (m·K).

[0076] In some embodiments, the compressive strength of the material is greater than or equal to 268 kPa, preferably greater than or equal to 300 kPa; for example, 268, 285, 300, 320 or 345 kPa.

[0077] In some embodiments, the sound insulation of the material is greater than or equal to 20 dB, preferably greater than or equal to 27 dB; for example, 20, 22, 25, 27, 30 or 32 dB.

[0078] In some embodiments, the continuous burning time of the material is less than or equal to 10 s, preferably 0 s; and / or, the furnace temperature rise of the material is less than or equal to 200°C, preferably less than or equal to 150°C (e.g., 105, 112, 118, 142 or 150°C); and / or, the residual rate of the material is greater than or equal to 33%, preferably greater than or equal to 40% (e.g., 40%, 45% or 52%).

[0079] In some embodiments, the polyurethane thermal insulation, flame retardant, and sound insulation material comprises a polyurethane matrix and sunflower stem pith powder, defatted rice bran powder, and cuttlebone porous powder dispersed in the polyurethane matrix; based on the total mass of the material, the sunflower stem pith powder is 0.8%~2.5% (e.g., 0.8%, 0.9%, 1.3%, 1.5%, 2.1%, or 2.5%), the defatted rice bran powder is 2.0%~6.0% (e.g., 2.0%, 2.3%, 3.5%, 4.7%, 5.1%, or 6.0%), and the cuttlebone porous powder is 1.0%~4.0% (e.g., 1.0%, 1.4%, 2.2%, 3.1%, 3.4%, or 4.0%). In some embodiments, the balance is the polyurethane matrix formed by reacting the combined polyols with the polymethylene polyphenyl polyisocyanate and conventional additives and / or unavoidable impurities. The conventional additives may include, for example, pentane blowing agents, amine catalysts, silicone surfactants, etc. In some embodiments, the polyurethane matrix content is, for example, 85.0% to 96% (e.g., 85.0%, 86.0%, 87.0%, 88.0%, 90.0%, 91.0%, 92.0%, 93.0%, 94.0%, 95.0%, or 96.0%). In some embodiments, the sum of the weight percentages of the above components is 100%.

[0080] In some embodiments, the present invention provides a polyurethane foam material, such as a polyurethane foam sound insulation material, comprising a polyurethane foam matrix and cuttlebone porous micropowder dispersed in the polyurethane foam matrix, wherein the cuttlebone porous micropowder has a layer-column three-dimensional interconnected pore structure. In some embodiments, the polyurethane foam is a rigid polyurethane foam; the sound insulation of the material is greater than or equal to 20 dB; the mesh size of the cuttlebone porous micropowder is 200-400 mesh, and its calcium carbonate content is greater than or equal to 85%. In some embodiments, the polyurethane foam sound insulation material further comprises sunflower stem pith micropowder to further impart thermal insulation properties to the material, thereby constituting a polyurethane foam thermal insulation and sound insulation material; in some embodiments, the polyurethane foam sound insulation material further comprises defatted rice bran micropowder to further impart flame retardant properties to the material, thereby constituting a polyurethane foam sound insulation and flame retardant material.

[0081] In some other embodiments, the present invention provides a polyurethane foam material whose functional filler comprises only sunflower stem pith powder.

[0082] In some other embodiments, the present invention provides a polyurethane foam material whose functional filler comprises only defatted rice bran powder.

[0083] In some other embodiments, the present invention provides a polyurethane foam material whose functional fillers include sunflower stem pith powder and defatted rice bran powder.

[0084] In some embodiments, the present invention provides a method for preparing any of the above-mentioned polyurethane thermal insulation, flame retardant, and sound insulation materials, comprising the following steps:

[0085] S1. Sunflower stem pith, defatted rice bran, and cuttlebone are ultrasonically cleaned to remove impurities, dried at a constant temperature to a constant weight, and then pulverized by low-speed physical shearing and sieved through a standard vibrating screen to obtain sunflower stem pith micro powder, defatted rice bran micro powder, and cuttlebone porous micro powder. During the pulverization of cuttlebone, high-energy ball milling and other processing methods that easily damage the pore structure are avoided. The sieve mesh size is controlled at 200~400 mesh to ensure that the natural layer-column three-dimensional interconnected pore structure of each micro powder is still intact.

[0086] S2. Weigh the combined polyol, sunflower stem pith powder, defatted rice bran powder, cuttlebone porous powder, foaming agent, foam stabilizer and catalyst according to the weight parts, mix and stir until uniformly dispersed to obtain component A;

[0087] S3. Using polymethylene polyphenyl polyisocyanate as component B, add component B to component A, stir and pour into a mold to allow it to foam freely;

[0088] S4. After curing, demolding and maintenance, the polyurethane thermal insulation, flame retardant and sound insulation material is obtained.

[0089] In some embodiments, the cleaning in S1 is ultrasonic cleaning, and the ultrasonic cleaning time is 10-30 min (e.g., 10 min, 20 min, or 30 min); the drying is drying to constant weight at 60-80°C (e.g., 60°C, 70°C, or 80°C); the pulverization is physical pulverization, with a pulverization speed of 10000-15000 r / min (e.g., 10000, 12000, or 15000 r / min), and sieving through a standard vibrating screen. In some embodiments, the particle size of the cuttlebone pulverized in S1 is controlled to be 200-400 mesh to retain its layer-column three-dimensional interconnected pore structure.

[0090] In some embodiments, in S2, the powders are first premixed at a low speed to initially disperse them, and then stirred at 1500~2000 r / min (e.g., 1500, 1800 or 2000 r / min) for 5~10 min (e.g., 5 min, 8 min or 10 min).

[0091] In some embodiments, the weight ratio of component A to component B in S3 is 0.9:1 to 1.3:1 (e.g., 1:1, 1:1.05, 1:1.10 or 1:1.20); after stirring at 3000 to 5000 r / min (e.g., 3000, 4000 or 5000 r / min) for 5 to 8 seconds (e.g., 5 seconds, 6 seconds or 8 seconds), it is poured into a mold preheated to 40 to 50°C (e.g., 40°C, 45°C or 50°C) within 10 seconds to allow it to foam freely.

[0092] In some embodiments, after curing at 25±2°C for at least 24 hours in S4, the material is demolded and then cured at 25±2°C and 50% relative humidity for at least 72 hours.

[0093] Example

[0094] The present invention will be further described below with reference to specific embodiments and comparative examples. The raw material ratios of each embodiment and comparative example are shown in Table 1 (unit: parts by weight). Among them, Examples 1-9 are polyurethane thermal insulation, flame retardant and sound insulation materials containing three functional fillers; Examples 10-12 are polyurethane foam materials containing only one functional filler; Comparative Examples 1-3 are pure polyurethane foam materials without functional fillers.

[0095] Table 1. Raw material ratios (parts by weight) for each embodiment and comparative example.

[0096] Example 1 100 105 2 5 3 4 2 1 Example 2 100 105 3 8 5 4 2 1 Example 3 100 105 5 12 8 4 2 1 Example 4 100 110 2 5 3 5 2.5 1.2 Example 5 100 110 3 8 5 5 2.5 1.2 Example 6 100 110 5 12 8 5 2.5 1.2 Example 7 100 120 2 5 3 6 3 1.5 Example 8 100 120 3 8 5 6 3 1.5 Example 9 100 120 5 12 8 6 3 1.5 Example 10 100 105 2 0 0 4 2 1 Example 11 100 105 0 8 0 4 2 1 Example 12 100 105 0 0 5 4 2 1 Comparative Example 1 100 105 0 0 0 4 2 1 Comparative Example 2 100 110 0 0 0 5 2.5 1.2 Comparative Example 3 100 120 0 0 0 6 3 1.5

[0097] In the above embodiments and comparative examples, except for the types and amounts of functional fillers (sunflower stem pith micro powder, defatted rice bran micro powder, and cuttlebone porous micro powder) which vary according to Table 1, the foaming agent, foam stabilizer, and catalyst components are all the same. Specifically, the foaming agent is a compound system composed of cyclopentane and deionized water at a weight ratio of 3:1; the foam stabilizer is a polyether-modified organosilicon foam stabilizer (brand name AK8805); and the catalyst is an amine-tin composite catalytic system composed of triethylenediamine and dibutyltin dilaurate at a weight ratio of 2:1. Specifically, the triethylenediamine is used in the form of a 33% (w / w) triethylenediamine solution, and the solvent is dipropylene glycol. The values ​​corresponding to the foaming agent, foam stabilizer, and catalyst in Table 1 are all the total amounts of the corresponding compound systems (or components) mentioned above.

[0098] Example 1

[0099] This embodiment provides a polyurethane thermal insulation, flame retardant, and sound insulation material, the preparation method of which includes the following steps:

[0100] S1. Preparation of functional filler micro powder: Sunflower stem pith, defatted rice bran and cuttlebone raw materials were collected and ultrasonically cleaned for 20 minutes to remove surface impurities, and dried at 70℃ to constant weight. The dried sunflower stem pith and defatted rice bran were placed in a high-speed pulverizer for physical pulverization and sieved through a standard vibrating screen to obtain sunflower stem pith micro powder and defatted rice bran micro powder respectively. The dried cuttlebone was physically pulverized and sieved, and its particle size was controlled to be 200~400 mesh to retain the layer-column three-dimensional interconnected pore structure of cuttlebone, so as to obtain cuttlebone porous micro powder for later use.

[0101] S2. Preparation of Component A: Weigh each raw material according to the proportions in Table 1. Add 100 parts of the combined polyol, 2 parts of sunflower stem pith micro powder, 5 parts of defatted rice bran micro powder, 3 parts of cuttlebone porous micro powder, 4 parts of foaming agent, 2 parts of foam stabilizer, and 1 part of catalyst to the stirrer in sequence. First, premix at low speed to initially disperse the functional filler, and then increase the speed to 1800 r / min and stir for 8 min to obtain a uniformly dispersed Component A.

[0102] S3. Mixing and foaming: Using polymethylene polyphenyl polyisocyanate as component B, add component B to component A according to the weight ratio of component A to component B, stir at high speed of 4000r / min for 6s, and then immediately pour into a mold preheated to 45℃ within 10s to allow it to foam freely.

[0103] S4. Curing and Molding: Place the mold in an environment of 25±2℃ for 24 hours to cure and then demold; after demolding, the product continues to be cured in a constant temperature and humidity environment of 25±2℃ and 50% relative humidity for more than 72 hours to obtain polyurethane thermal insulation, flame retardant and sound insulation material.

[0104] In the polyurethane thermal insulation, flame retardant and sound insulation material obtained in this embodiment, the total mass of the product is approximately 0.9% sunflower stem pith powder, approximately 2.3% defatted rice bran powder, and approximately 1.4% cuttlebone porous powder.

[0105] Example 2

[0106] This embodiment provides a polyurethane thermal insulation, flame retardant, and sound insulation material and its preparation method. The difference from Embodiment 1 is that the amount of defatted rice bran micro powder added to the functional filler is 8 parts, the amount of cuttlebone porous micro powder added is 5 parts, and the amount of sunflower stem pith micro powder added is 3 parts, as shown in Table 1. The preparation method involved in this embodiment is the same as in Embodiment 1.

[0107] In the polyurethane thermal insulation, flame retardant and sound insulation material obtained in this embodiment, the total mass of the product is approximately 1.3% sunflower stem pith powder, approximately 3.5% defatted rice bran powder, and approximately 2.2% cuttlebone porous powder.

[0108] Example 3

[0109] This embodiment provides a polyurethane thermal insulation, flame retardant, and sound insulation material and its preparation method. The difference from Embodiment 1 is that the amount of defatted rice bran micro powder added to the functional filler is 12 parts, the amount of cuttlebone porous micro powder added is 8 parts, and the amount of sunflower stem pith micro powder added is 5 parts, as shown in Table 1. The preparation method involved in this embodiment is the same as in Embodiment 1.

[0110] In the polyurethane thermal insulation, flame retardant and sound insulation material obtained in this embodiment, by total product weight, sunflower stem pith micro powder is about 2.1%, defatted rice bran micro powder is about 5.1%, and cuttlebone porous micro powder is about 3.4%.

[0111] Example 4

[0112] This embodiment provides a polyurethane thermal insulation, flame retardant, and sound insulation material and its preparation method. Similar to Embodiment 1, the difference lies in the proportion of functional fillers; the mass ratio of component A to component B is 1:1.10, the amount of foaming agent added is 5 parts, the amount of foam stabilizer added is 2.5 parts, and the amount of catalyst added is 1.2 parts, as shown in Table 1. The preparation method involved in this embodiment is the same as in Embodiment 1.

[0113] In the polyurethane thermal insulation, flame retardant and sound insulation material obtained in this embodiment, the total mass of the product is approximately 0.9% sunflower stem pith powder, approximately 2.2% defatted rice bran powder, and approximately 1.3% cuttlebone porous powder.

[0114] Example 5

[0115] This embodiment provides a polyurethane thermal insulation, flame retardant, and sound insulation material and its preparation method. It is similar to Example 4 in the mass ratio of component A to component B and the ratio of additives. The difference lies in the addition amount of defatted rice bran micro powder (8 parts), cuttlebone porous micro powder (5 parts), and sunflower stem pith micro powder (3 parts) in the functional filler, as shown in Table 1. The preparation method involved in this embodiment is the same as in Example 1.

[0116] In the polyurethane thermal insulation, flame retardant and sound insulation material obtained in this embodiment, by total product weight, sunflower stem pith micro powder is about 1.3%, defatted rice bran micro powder is about 3.4%, and cuttlebone porous micro powder is about 2.1%.

[0117] Example 6

[0118] This embodiment provides a polyurethane thermal insulation, flame retardant, and sound insulation material and its preparation method. It is similar to Example 4 in the mass ratio of component A to component B and the ratio of additives. The difference lies in the addition amount of defatted rice bran micro powder (12 parts), cuttlebone porous micro powder (8 parts), and sunflower stem pith micro powder (5 parts) in the functional filler, as shown in Table 1. The preparation method involved in this embodiment is the same as in Example 1.

[0119] In the polyurethane thermal insulation, flame retardant and sound insulation material obtained in this embodiment, by total product weight, sunflower stem pith micro powder is about 2.1%, defatted rice bran micro powder is about 4.9%, and cuttlebone porous micro powder is about 3.3%.

[0120] Example 7

[0121] This embodiment provides a polyurethane thermal insulation, flame retardant, and sound insulation material and its preparation method. Similar to Example 1, the difference lies in the proportion of functional fillers; the mass ratio of component A to component B is 1:1.20, the amount of foaming agent added is 6 parts, the amount of foam stabilizer added is 3 parts, and the amount of catalyst added is 1.5 parts, as shown in Table 1. The preparation method involved in this embodiment is the same as in Example 1.

[0122] In the polyurethane thermal insulation, flame retardant and sound insulation material obtained in this embodiment, by total product weight, sunflower stem pith micro powder is about 0.8%, defatted rice bran micro powder is about 2.1%, and cuttlebone porous micro powder is about 1.2%.

[0123] Example 8

[0124] This embodiment provides a polyurethane thermal insulation, flame retardant, and sound insulation material and its preparation method. It is similar to Example 7 in the mass ratio of component A to component B and the ratio of additives. The difference lies in the addition amount of defatted rice bran micro powder (8 parts), cuttlebone porous micro powder (5 parts), and sunflower stem pith micro powder (3 parts) in the functional filler, as shown in Table 1. The preparation method involved in this embodiment is the same as in Example 1.

[0125] In the polyurethane thermal insulation, flame retardant and sound insulation material obtained in this embodiment, by total product weight, sunflower stem pith micro powder is about 1.2%, defatted rice bran micro powder is about 3.2%, and cuttlebone porous micro powder is about 2.0%.

[0126] Example 9

[0127] This embodiment provides a polyurethane thermal insulation, flame retardant, and sound insulation material and its preparation method. It is similar to Example 7 in the mass ratio of component A to component B and the ratio of additives. The difference lies in the addition amount of defatted rice bran micro powder (12 parts), cuttlebone porous micro powder (8 parts), and sunflower stem pith micro powder (5 parts) in the functional filler, as shown in Table 1. The preparation method involved in this embodiment is the same as in Example 1.

[0128] In the polyurethane thermal insulation, flame retardant and sound insulation material obtained in this embodiment, by total product weight, sunflower stem pith micro powder is about 2.0%, defatted rice bran micro powder is about 4.7%, and cuttlebone porous micro powder is about 3.1%.

[0129] In Examples 2-9 above, the amount of functional filler used in Examples 2 and 3 is increased accordingly according to Table 1; in Examples 4-6, the amounts of foaming agent, foam stabilizer, and catalyst are adjusted to 5 parts, 2.5 parts, and 1.2 parts, respectively, and the weight ratio of component A to component B is adjusted accordingly; in Examples 7-9, the amounts of foaming agent, foam stabilizer, and catalyst are adjusted to 6 parts, 3 parts, and 1.5 parts, respectively, and the weight ratio of component A to component B is adjusted accordingly.

[0130] Example 10

[0131] This embodiment provides a polyurethane foam material containing only sunflower stem pith micro powder as a functional filler. Its preparation method is the same as that of Example 1 except for the operations involved in the following differences. The only difference is that only 2 parts of sunflower stem pith micro powder are added as functional filler, and defatted rice bran micro powder and cuttlebone porous micro powder are not added. The proportions are shown in Table 1.

[0132] In the polyurethane foam material obtained in this embodiment, the sunflower stem pith powder is about 0.9% by total product weight (excluding defatted rice bran powder and cuttlebone porous powder).

[0133] Example 11

[0134] This embodiment provides a polyurethane foam material containing only defatted rice bran micro powder as a functional filler. Its preparation method is the same as that of Example 1 except for the operations involved in the following differences. The only difference is that only 8 parts of defatted rice bran micro powder are added as functional filler, and sunflower stem pith micro powder and cuttlebone porous micro powder are not added. The proportions are shown in Table 1.

[0135] In the polyurethane foam material obtained in this embodiment, the defatted rice bran powder is about 3.6% by total product mass (excluding sunflower stem pith powder and cuttlebone porous powder).

[0136] Example 12

[0137] This embodiment provides a polyurethane foam material containing only cuttlebone porous micro powder as a functional filler. Its preparation method is the same as in Example 1, except for the operations described below, where the only difference is that only 5 parts of cuttlebone porous micro powder are added as the functional filler; sunflower stem pith powder and defatted rice bran powder are not added. The proportions are shown in Table 1. The cuttlebone porous micro powder retains a layer-column three-dimensional interconnected pore structure.

[0138] In the polyurethane foam sound insulation material obtained in this embodiment, the cuttlebone porous micro powder is about 2.3% by total product weight (excluding sunflower stem pith micro powder and defatted rice bran micro powder).

[0139] In the above embodiments 10-12, two types of functional fillers are omitted in turn, and only a single-function filler is retained.

[0140] Comparative Example 1

[0141] This comparative example provides a pure polyurethane insulation material and its preparation method. The materials used include a combination of polyols, polymethylene polyphenyl polyisocyanates, a blowing agent, a foam stabilizer, and a catalyst. The formulations of the combination of polyols, blowing agent, foam stabilizer, and catalyst are exactly the same as in Examples 1, 2, and 3, except that no functional fillers are added, i.e., it does not contain sunflower stem pith powder, defatted rice bran powder, or cuttlebone porous powder. The proportions are shown in Table 1. The preparation method involved in this comparative example is the same as in Example 1, except for the operation involving the functional fillers.

[0142] Comparative Example 2

[0143] This comparative example provides a pure polyurethane insulation material and its preparation method. The materials used are exactly the same as those in Comparative Example 1. The formulations of the combined polyol, foaming agent, foam stabilizer, and catalyst are exactly the same as those in Examples 4, 5, and 6. The difference is that no functional fillers are added, and the formulations are shown in Table 1. The preparation method involved in this comparative example is the same as that in Example 1, except for the operation involving the functional fillers.

[0144] Comparative Example 3

[0145] This comparative example provides a pure polyurethane insulation material and its preparation method. The materials used are exactly the same as those in Comparative Example 1. The formulations of the combined polyol, foaming agent, foam stabilizer, and catalyst are exactly the same as those in Examples 7, 8, and 9. The difference is that no functional fillers are added, and the formulations are shown in Table 1. The preparation method involved in this comparative example is the same as that in Example 1, except for the operation involving the functional fillers.

[0146] In Comparative Examples 1 to 3, a pure polyurethane foam material without any functional fillers was provided.

[0147] To evaluate the performance of the materials prepared in Examples 1-12 and Comparative Examples 1-3 of the present invention, the thermal insulation, mechanical, flame retardant and sound insulation performance of each group of samples were tested according to the following method.

[0148] (1) Thermal conductivity: The test was conducted according to GB / T10294-2008 "Determination of steady-state thermal resistance and related properties of thermal insulation materials by protective hot plate method". The specimen size was 300mm×300mm×30mm and the average test temperature was 25℃.

[0149] (2) Apparent density: Determined according to GB / T6343-2009 "Determination of apparent density of foamed plastics and rubber".

[0150] (3) Compression strength: The compression strength was determined in accordance with GB / T8813-2020 "Determination of compression properties of rigid foamed plastics". The specimen size was 100mm×100mm×50mm and the compression rate was 5mm / min.

[0151] (4) Flame retardant performance: Refer to the test procedure of GB / T5464-2010 "Test method for non-combustibility of building materials" to determine the furnace temperature rise, continuous burning time and combustion residue rate (the percentage of the residual mass of the sample after combustion to the total mass of the sample before combustion) of each group of samples, so as to evaluate the flame retardant modification effect of functional fillers on polyurethane foam.

[0152] (5) Sound insulation (transmission loss): Refer to GB / T 32385-2015 "Measurement of transmission loss in acoustic impedance tube by transfer matrix method", the airborne sound insulation of each group of samples was determined by acoustic impedance tube method. The diameter of the sample was 100 mm and the thickness was 30 mm.

[0153] The test results of thermal insulation and mechanical properties of each group of samples are shown in Table 2, the test results of flame retardant properties are shown in Table 3, and the test results of sound insulation properties are shown in Table 4.

[0154] Table 2 Results of Thermal Insulation and Mechanical Properties Tests

[0155] Example 1 285 48 0.024 Example 2 310 52 0.023 Example 3 345 56 0.022 Example 4 275 47 0.025 Example 5 305 51 0.024 Example 6 340 55 0.023 Example 7 268 46 0.026 Example 8 298 50 0.025 Example 9 332 54 0.024 Example 10 230 42 0.025 Example 11 210 41 0.027 Example 12 248 44 0.026 Comparative Example 1 195 38 0.028 Comparative Example 2 188 37 0.029 Comparative Example 3 182 36 0.030

[0156] Note: The compressive strength of rigid polyurethane foam for construction should generally not be less than 150 kPa, and the thermal conductivity should generally not be higher than 24.0 mW / (m·K) (i.e. 0.024 W / (m·K)).

[0157] Table 3 Flame retardant performance test results

[0158] Example 1 185 35.2 5 Example 2 142 43.8 0 Example 3 105 52.1 0 Example 4 192 34.6 8 Example 5 148 42.5 0 Example 6 112 51.3 0 Example 7 198 33.8 10 Example 8 153 41.7 0 Example 9 118 50.9 0 Example 10 365 12.4 38 Example 11 155 41.2 0 Example 12 340 18.6 25 Comparative Example 1 420 5.2 65 Comparative Example 2 435 4.8 72 Comparative Example 3 448 4.3 78

[0159] Note: The lower the temperature rise in the furnace, the shorter the continuous burning time, and the higher the combustion residue rate, the better the flame retardant and smoke-suppressing performance of the material. This set of tests is used to compare the relative improvement of the flame retardant performance of the material under different formulations.

[0160] Table 4 Sound insulation performance test results

[0161] Example 1 22 Example 2 27 Example 3 32 Example 4 21 Example 5 26 Example 6 31 Example 7 20 Example 8 25 Example 9 30 Example 10 17 Example 11 18 Example 12 27 Comparative Example 1 15 Comparative Example 2 14 Comparative Example 3 13

[0162] Note: The sound insulation value in the table is the airborne sound transmission loss, which is a quantitative indicator characterizing the sound insulation performance of materials. The unit is decibel (dB); the higher the value, the stronger the material's ability to block sound transmission.

[0163] Results Analysis

[0164] Examples 1-12 are superior to Comparative Examples 1-3 in multiple dimensions. Comparative Examples 1-3 are pure polyurethane foam without any functional fillers, with a compressive strength of only 182-195 kPa, an oven temperature rise of 420-448°C, a continuous burning time of 65-78 s (with a residual rate of only 4.3%-5.2%), and a sound insulation of only 13-15 dB. Apart from decent thermal insulation, their mechanical, flame-retardant, and sound insulation properties are poor. After introducing functional fillers, Examples 1-12 show improved overall performance compared to Comparative Examples 1-3: compressive strength increases to 210-345 kPa, thermal conductivity remains at a low level of 0.022-0.027 W / (m·K), and flame-retardant and sound insulation properties are also improved to varying degrees (sound insulation increases to 17-32 dB).

[0165] Examples 1-9 and 12, which contain porous cuttlebone powder, are significantly superior to Comparative Examples 1-3 in multiple dimensions, and also show a significant improvement in sound insulation performance compared to Examples 10-11, which do not contain cuttlebone. Examples 1-9 and 12 all use porous cuttlebone powder that retains the natural layer-column pore structure. Their airborne sound insulation (i.e., transmission loss, 20-32 dB for Examples 1-9 and 27 dB for Example 12) is significantly higher than that of Comparative Examples 1-3 (13-15 dB), and also significantly higher than that of Examples 10 (containing only sunflower stem pith powder, 17 dB) and 11 (containing only defatted rice bran powder, 18 dB), which do not contain porous cuttlebone powder. Simultaneously, their compressive strength and other mechanical properties are not lower than those of Examples 10 and 11.

[0166] In an interpretive rather than restrictive sense, the sound insulation enhancement effect of cuttlebone primarily depends on the preservation of its natural layered-columnar three-dimensional interconnected porous structure. If cuttlebone is ground into amorphous calcium carbonate powder that disrupts the pores, as is common in existing technologies, it can only provide limited flame retardant effects and is unlikely to achieve a significant improvement in sound insulation. In other words, compared to pure polyurethane foam and filler solutions that do not contain porous cuttlebone powder, porous cuttlebone powder that retains its porous structure can achieve a substantial improvement in sound insulation performance without significantly deteriorating thermal insulation and mechanical properties—a technical effect that existing cuttlebone powder methods that disrupt the pores cannot achieve.

[0167] Examples 1-9, which contain three functional fillers, not only show significant improvements over Comparative Examples 1-3 in multiple dimensions, but are also significantly superior to Examples 10-12. Compared to Comparative Examples 1-3, the overall performance of Examples 1-9 is greatly improved: compressive strength increases from 182-195 kPa to 268-345 kPa, furnace temperature rise decreases from 420-448℃ to 105-198℃, continuous combustion time decreases from 65-78s to 0-10s (Examples 2, 3, 5, 6, 8, and 9 are all 0s), residual rate increases from 4.3%-5.2% to 33.8%-52.1%, and sound insulation increases from 13-15dB to 20-32dB, while maintaining a low thermal conductivity of 0.022-0.026 W / (m·K). That is, while maintaining thermal insulation performance comparable to pure polyurethane foam, it is significantly superior to pure polyurethane foam in multiple aspects such as flame retardancy, sound insulation, and mechanical properties. Compared to Examples 10-12, which only contain single-function fillers, Examples 1-9 also have obvious advantages: Examples 10-12 each perform well in only one aspect—Example 10 has good thermal insulation (thermal conductivity 0.025W / (m·K)) but poor flame retardancy (38s of continuous burning) and poor sound insulation (17dB); Example 11 has good flame retardancy (0s of continuous burning) but average thermal insulation (0.027W / (m·K)) and poor sound insulation (18dB); Example 12 has good sound insulation and mechanical properties (27dB, 248kPa) but poor flame retardancy (25s of continuous burning); while Examples 1-9 simultaneously possess excellent thermal insulation, flame retardancy, sound insulation and mechanical properties, achieving the integration of multiple functions of thermal insulation, flame retardancy and sound insulation, which cannot be achieved simultaneously by any example containing only a single-function filler.

[0168] In summary, some embodiments / examples of the present invention introduce three natural biological solid waste fillers—sunflower stem pith powder, defatted rice bran powder, and cuttlebone porous powder—into a polyurethane foam system. This allows the material to maintain excellent thermal insulation performance (thermal conductivity 0.022~0.026 W / (m·K)), while also achieving good flame retardant performance (burning time can be reduced to 0s) and sound insulation performance (sound insulation can reach 32dB), and high mechanical strength (compressive strength can reach 345kPa). This achieves the integration of multiple functions such as thermal insulation, flame retardancy, and sound insulation, as well as the high-value utilization of agricultural, forestry, and marine biological solid waste.

[0169] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0170] This document describes several embodiments of the present invention; however, for the sake of brevity, the descriptions of the embodiments are not exhaustive, and identical or similar features or parts between the embodiments may be omitted. In this document, "one embodiment," "some embodiments," "example," "specific example," or "some examples" refers to embodiments applicable to at least one, but not all, of the present invention. The above terms do not necessarily refer to the same embodiments or examples. Without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described herein, as well as the features of the different embodiments or examples.

Claims

1. A polyurethane thermal insulation, flame retardant, and sound insulation material, characterized in that, The product comprises the following raw materials: a combination of polyols, polymethylene polyphenyl polyisocyanates, sunflower stem pith powder, defatted rice bran powder, cuttlebone porous powder, a foaming agent, a foam stabilizer, and a catalyst; wherein, by weight, the combination of polyols comprises 100 parts, polymethylene polyphenyl polyisocyanates comprises 105-120 parts, sunflower stem pith powder comprises 2-5 parts, defatted rice bran powder comprises 5-12 parts, and cuttlebone porous powder comprises 3-8 parts; wherein, the cuttlebone porous powder has a layer-column three-dimensional interconnected pore structure.

2. The polyurethane thermal insulation, flame retardant, and sound insulation material according to claim 1, characterized in that, The porous cuttlebone powder has a mesh size of 200-400 mesh; based on the weight of the porous cuttlebone powder, it contains greater than or equal to 85% calcium carbonate.

3. The polyurethane thermal insulation, flame retardant, and sound insulation material according to claim 1, characterized in that, The defatted rice bran powder has a mesh size of 200-400 mesh; by weight, the defatted rice bran powder contains 10%-15% phytic acid, 15%-20% rice bran protein and 40%-50% cellulose.

4. The polyurethane thermal insulation, flame retardant, and sound insulation material according to claim 1, characterized in that, The sunflower stem pith powder has a mesh size of 100-200 and a bulk density of 0.02-0.05 g / cm³. Based on the weight of the sunflower stem pith powder, the sunflower stem pith powder contains greater than or equal to 40% cellulose and 15%-25% lignin.

5. The polyurethane thermal insulation, flame retardant, and sound insulation material according to claim 1, characterized in that, The combined polyol is composed of polyether polyol and bio-based polyol mixed in a weight ratio of 3:1 to 5:

1.

6. The polyurethane thermal insulation, flame retardant, and sound insulation material according to claim 5, characterized in that, The bio-based polyol is selected from at least one of castor oil-based polyol, epoxidized soybean oil-based polyol, and rosin ester polyol.

7. The polyurethane thermal insulation, flame retardant, and sound insulation material according to claim 1, characterized in that, The foaming agent comprises 3-6 parts by weight, the foam stabilizer comprises 1.5-3 parts by weight, and the catalyst comprises 0.5-1.5 parts by weight. The foaming agent is selected from at least one of cyclopentane and water, the foam stabilizer is an organosilicon foam stabilizer, and the catalyst is selected from at least one of amine catalysts and tin catalysts.

8. The polyurethane thermal insulation, flame retardant, and sound insulation material according to claim 7, characterized in that, The foaming agent is a compound system composed of cyclopentane and deionized water in a weight ratio of 3:1; the foam stabilizer is a polyether-modified organosilicon foam stabilizer; and the catalyst is an amine-tin composite catalytic system composed of triethylenediamine and dibutyltin dilaurate in a weight ratio of 2:

1.

9. The polyurethane thermal insulation, flame retardant, and sound insulation material according to claim 1, characterized in that, The combination of polyol, sunflower stem pith powder, defatted rice bran powder, cuttlebone porous powder, foaming agent, foam stabilizer and catalyst is used as component A, and the polymethylene polyphenyl polyisocyanate is used as component B. The weight ratio of component A to component B is 0.9:1 to 1.3:

1.

10. A polyurethane thermal insulation, flame retardant, and sound insulation material, characterized in that, The product comprises a polyurethane matrix and sunflower stem pith micropowder, defatted rice bran micropowder, and cuttlebone porous micropowder dispersed in the polyurethane matrix; by weight percentage of the finished product, the sunflower stem pith micropowder is 0.8%~2.5%, the defatted rice bran micropowder is 2.0%~6.0%, and the cuttlebone porous micropowder is 1.0%~4.0%; wherein the cuttlebone porous micropowder has a layer-column three-dimensional interconnected pore structure.

11. A method for preparing a polyurethane thermal insulation, flame retardant, and sound insulation material according to any one of claims 1 to 9, characterized in that, Includes the following steps: S1. After washing, drying, pulverizing and sieving sunflower stem pith, defatted rice bran and cuttlebone respectively, sunflower stem pith micro powder, defatted rice bran micro powder and cuttlebone porous micro powder are obtained respectively. The particle size of the cuttlebone is controlled to retain its layer-column three-dimensional interconnected pore structure. S2. Weigh the combined polyol, sunflower stem pith powder, defatted rice bran powder, cuttlebone porous powder, foaming agent, foam stabilizer and catalyst according to the weight parts, mix and stir until uniformly dispersed to obtain component A; S3. Using polymethylene polyphenyl polyisocyanate as component B, add component B to component A, stir and pour into a mold to allow it to foam freely; S4. After curing, demolding and maintenance, the polyurethane thermal insulation, flame retardant and sound insulation material is obtained.

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