Degradable biomass foam heat-insulation fireproof heat-preservation material and preparation method thereof

Abstract

The invention discloses a degradable biomass foam heat-insulation fireproof heat-preservation material which is prepared from the following raw materials in parts by weight: 1-10 parts of a recycled fiber material, 0.1-2 parts of a foaming agent and 190-200 parts of water, the preparation raw materials also comprise a water-soluble polymer, a cross-linking agent, a flame retardant and a biomass filler. The recycled fiber material is adopted to replace a traditional petroleum-based foam material, carbon emission and soil pollution caused by waste paper discarding are avoided, meanwhile, high energy consumption and non-degradability of petrochemical material production are avoided, and excellent environment friendliness is achieved. The natural porous structure of the water-soluble polymer is matched with the foaming agent, so that the distribution uniformity of foam holes is improved, the apparent density and compression strength of the material are excellent, the material has good heat insulation performance, and meanwhile, noise can be effectively absorbed and isolated. Meanwhile, the flame retardant property is excellent, the size of the material is stable, and deformation caused by moisture absorption or thermal expansion is avoided.

Description

Technical Field

[0001] The present invention relates to the field of polymer material compositions, and in particular to a degradable biomass foam heat-insulating, fire-proof and heat-preserving material and a preparation method thereof. Background Art

[0002] Foam materials are widely used in packaging, construction, transportation and other fields. Existing polymer foam materials are non-degradable. Not only do they consume a large amount of natural resources in their production, but they also pollute the environment after being discarded. The use of biomass foam materials to replace traditional foam materials is the current trend of sustainable development. Existing biomass foam materials have insufficient mechanical properties and are flammable. Improving flame retardancy by introducing inorganic flame retardants will inevitably affect some environmental protection. The thermal insulation performance can be improved by foaming and modifying biomass foam materials, but the existing chemical foaming methods may have toxic residues, and the biological foaming method has a long production cycle and high cost. Therefore, it is crucial to develop a biomass foam thermal insulation and fireproofing material that balances environmental protection, functionality and cost.

[0003] Chinese invention patent application CN115340879A discloses an environmentally friendly bamboo charcoal-based flame retardant material and its preparation and application. The material combines powdered bamboo charcoal, a nitrogen-containing compound, a coupling agent, hydroxymethyl cellulose and its salts, and ammonium polyphosphate to achieve environmental safety, good mechanical strength, and mechanical properties, but lacks thermal insulation. Chinese invention patent application CN106045429A discloses a preparation method and construction method for a novel powdered exterior wall insulation material. The raw materials include calcium stearate, polypropylene fiber, elastic emulsion, nanocement additive, self-extinguishing polystyrene particles, flame retardant, ceramic wool fiber, aluminum silicate fiber wool, cellulose ether, foam, sulfoaluminate cement, and water. This material overcomes the serious drawbacks of traditional thermal insulation materials, such as poor fire resistance and environmental concerns. However, the composite material is non-degradable, leading to high waste disposal costs. Summary of the Invention

[0004] In order to develop a biomass foam thermal insulation and fireproof thermal insulation material that balances environmental protection, functionality and cost, the first aspect of the present invention provides a degradable biomass foam thermal insulation and fireproof thermal insulation material, the preparation raw materials include, by weight: 1-10 parts of recycled fiber material, 0.1-2 parts of foaming agent, and 190-200 parts of water; the preparation raw materials also include water-soluble polymers, cross-linking agents, flame retardants, and biomass fillers.

[0005] As an embodiment, the flame retardant is a phosphorus-based flame retardant, and the added amount of the flame retardant is 0.5-2 parts by weight.

[0006] As an embodiment, the flame retardant is added in an amount of 0.5-2 parts by weight.

[0007] As an embodiment, the phosphorus-based flame retardant includes at least one of ammonium polyphosphate, aluminum hypophosphite, melamine phosphate, red phosphorus, polyphosphonate or hydroxyapatite.

[0008] As an embodiment, the flame retardant is ammonium polyphosphate.

[0009] As an embodiment, the biomass filler includes at least one of clay, attapulgite, kaolin, lignin, starch, chitosan, protein-based filler or biochar, and the added amount of the biomass filler is 2-8 parts by weight.

[0010] As an embodiment, the biomass filler is clay.

[0011] As an embodiment, the added amount of the biomass filler is 2-8 parts by weight.

[0012] This application uses clay as a biomass filler in combination with recycled fiber materials. This material resists decomposition when heated and forms a physical barrier, slowing the transfer of oxygen and heat into the material, thereby delaying combustion. Compared to synthetic flame retardants, clay is more economical and environmentally friendly, avoiding the drawbacks of relying solely on flame retardants for flame retardancy. Furthermore, the clay's layered structure acts as a reinforcing filler, increasing the compressive strength and rigidity of the biomass foam. It also improves the material's dimensional stability and reduces deformation caused by moisture absorption or thermal expansion.

[0013] As an embodiment, the added amount of the cross-linking agent is 0.1-0.5 parts by weight.

[0014] As an embodiment, the added amount of the cross-linking agent is 0.1-0.5 parts by weight.

[0015] As an embodiment, the crosslinking agent includes at least one of a nitrogen-containing polymer crosslinking agent, a carboxylic acid crosslinking agent, a polyphenol crosslinking agent, an aldehyde crosslinking agent or an epoxy polymer crosslinking agent.

[0016] As an embodiment, the crosslinking agent includes but is not limited to at least one of polyamide epichlorohydrin, citric acid modified sodium hypophosphite, carboxymethyl cellulose grafted polyacrylic acid, tannic acid, glyoxal, glutaraldehyde, polyethylene glycol diglycidyl ether or polyoxypropylene polyoxyethylene glycerol ether.

[0017] As an embodiment, the cross-linking agent is polyamide epichlorohydrin.

[0018] As an embodiment, the water-soluble polymer includes at least one of carboxymethyl cellulose salt, hydroxy cellulose, methyl cellulose, guar gum, gum arabic, hydroxypropyl methyl cellulose, sodium alginate, sodium polyacrylate or ethyl cellulose, and the added amount of the water-soluble polymer is 0.2-0.5 parts by weight.

[0019] As an embodiment, the water-soluble polymer is sodium carboxymethyl cellulose.

[0020] In this application, polyamide epichlorohydrin, recycled fiber material and sodium carboxymethyl cellulose are combined to introduce carboxymethyl groups into the molecular chain of sodium carboxymethyl cellulose, making it hydrophilic and ionic. It is an anionic polyelectrolyte that dissociates into Na + and a negatively charged cellulose backbone. Dissolving in water, it forms a high-viscosity solution with thickening, stabilizing, and film-forming capabilities. Polyamide epichlorohydrin, through the azetidinyl group, forms covalent bonds with the carboxyl and hydroxyl groups of recycled fiber materials and sodium carboxymethyl cellulose under heating conditions, improving the material's wet strength and thermal stability. The combination of polyamide epichlorohydrin, recycled fiber materials, and sodium carboxymethyl cellulose forms a stable network structure under mild conditions that remains structurally stable in humid environments, enhancing its moisture resistance and durability.

[0021] As an embodiment, the foaming agent is at least one of an anionic surfactant, a zwitterionic surfactant or a nonionic surfactant, and the HLB value of the foaming agent is 15-40.

[0022] As an embodiment, the foaming agent includes but is not limited to at least one of alkyl sulfate, alkyl sulfonate, sodium laureth sulfate, α-olefin sulfonate, sodium lauroyl sarcosinate, cocamidopropyl hydroxysulfobetaine, lauryl dimethylamine oxide or Tween.

[0023] As an embodiment, the foaming agent is sodium lauryl sulfate.

[0024] The present invention adopts sodium lauryl sulfate as a foaming agent to produce a stable foam structure. The hydrophobic long-chain alkyl group and the hydrophilic sulfate group are easily soluble in water and can significantly reduce the surface tension of the liquid, so that the cellulose pulp produces uniform and stable foam cells.

[0025] As an embodiment, the recycled fiber material is a cellulose material prepared by crushing paper products.

[0026] As an embodiment, the paper product includes but is not limited to at least one of office paper, household paper, wrapping paper, printing paper, industrial paper, and container paper.

[0027] A second aspect of the present invention provides a method for preparing a degradable biomass foam thermal insulation and fireproofing material, comprising the following steps:

[0028] S1: Preparation of recycled fiber material;

[0029] S2: sequentially mixing the recycled fiber material, foaming agent, water-soluble polymer, cross-linking agent, flame retardant, biomass filler and water, crushing and stirring at 30,000-40,000 rpm for 1-5 minutes to obtain cellulose pulp foam;

[0030] S3: placing the cellulose pulp foam into a mesh mold and letting it stand, drain, and set;

[0031] S4: Drying at 70-90° C. for 10-15 hours to obtain a biomass foam thermal insulation and fireproof heat preservation material.

[0032] As an embodiment, the method for preparing the recycled fiber material includes the following steps: removing impurities from paper products, and crushing at 30,000-40,000 rpm for 1-3 minutes to obtain the recycled fiber material.

[0033] As an embodiment, the paper product impurity removal includes but is not limited to removing impurities such as ink, film, stains, tape, etc. on the surface of the paper product.

[0034] As an embodiment, the drying method is air drying.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] (1) The biodegradable biomass foam thermal insulation and fireproofing material of the present invention uses recycled fiber materials to replace traditional petroleum-based foam materials, thereby avoiding carbon emissions and soil pollution caused by waste paper disposal, while avoiding the high energy consumption and non-degradability of petrochemical material production, and having excellent environmental protection.

[0037] (2) The biodegradable biomass foam thermal insulation and fireproofing material of the present invention adopts the natural porous structure of water-soluble polymer and foaming agent to improve the uniformity of the distribution of foam cells, and the apparent density and compressive strength of the material are excellent.

[0038] (3) The biodegradable biomass foam heat-insulating and fire-proof heat-preserving material of the present invention uses sodium carboxymethyl cellulose and sodium lauryl sulfate to form a porous structure, which has good heat-insulating properties and can effectively absorb and isolate noise.

[0039] (4) The cross-linking reaction between polyamide epichlorohydrin and sodium carboxymethyl cellulose in the biodegradable biomass foam thermal insulation and fireproofing material of the present invention improves the wet strength and thermal stability of the material. The formed cross-linked network improves moisture resistance and durability, and also has certain antibacterial properties.

[0040] (5) The recycled fiber material and clay in the biodegradable biomass foam thermal insulation and fireproofing material of the present invention are not easily decomposed when heated, and can form a physical barrier to slow down the transfer of oxygen and heat into the interior of the material, thereby delaying combustion, avoiding relying solely on flame retardants to enhance the flame retardant effect, while improving the compressive strength and rigidity of the biomass foam material, and also improving the dimensional stability of the material, reducing deformation caused by moisture absorption or thermal expansion. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a flow chart of the biomass foam thermal insulation and fireproofing material prepared in Example 19.

[0042] Figure 2 From left to right are the actual photos of the biomass foam thermal insulation and fireproof heat preservation materials prepared in Examples 1-4; top: photo after standing and shaping in step S3; bottom: photo after drying in step S4.

[0043] Figure 3 From left to right are the actual photos of the biomass foam thermal insulation and fireproof heat preservation materials prepared in Examples 5-8; top: photo after standing and shaping in step S3; bottom: photo after drying in step S4.

[0044] Figure 4 From left to right are the actual photos of the biomass foam thermal insulation and fireproof heat preservation materials prepared in Examples 9-13; top: photo after standing and shaping in step S3; bottom: photo after drying in step S4.

[0045] Figure 5 From left to right are the actual photos of the biomass foam thermal insulation and fireproof heat preservation materials prepared in Examples 14-16; top: photo after standing and shaping in step S3; bottom: photo after drying in step S4.

[0046] Figure 6 From left to right are the actual photos of the biomass foam thermal insulation and fireproof heat preservation materials prepared in Examples 17-19; top: photo after standing and shaping in step S3; bottom: photo after drying in step S4.

[0047] Figure 7 These are photos of water resistance tests of the biomass foam thermal insulation and fireproofing materials prepared in Example 3, Example 11, Example 12, and Example 13. From top to bottom, they are photos taken after immersion in distilled water for 0 days, 3 days, 5 days, 10 days, and 25 days; from left to right, they are Example 3, Example 11, Example 12, and Example 13.

[0048] Figure 8These are photos of soil degradation tests of the biomass foam thermal insulation and fireproofing materials prepared in Example 3, Example 15, and Example 19. From top to bottom, they are photos after 0 days, 15 days, and 30 days of landfill in the soil; from left to right, they are Example 3, Example 15, and Example 19.

[0049] Figure 9 These are photos of the combustion tests of the biomass foam thermal insulation and fireproofing materials prepared in Example 1, Example 15, and Example 19, from top to bottom are Example 1, Example 15, and Example 19; from left to right are photos during the combustion test.

[0050] Figure 10 These are photos of thermal insulation performance tests, in which: left: blank; middle: polystyrene foam (XPS); right: biomass foam thermal insulation and fireproofing material prepared in Example 19.

[0051] Figure 11 This is a graph showing how the insulation temperature of the material changes over time at different positions. The figure shows positions a, b, c, and d of the actual object. DETAILED DESCRIPTION

[0052] Example

[0053] A degradable biomass foam thermal insulation and fireproofing material, the raw materials for preparation are shown in Table 1 in parts by weight:

[0054] Table 1

[0055]

[0056]

[0057] A method for preparing a degradable biomass foam thermal insulation and fireproofing material comprises the following steps:

[0058] S1: Preparation of recycled fiber material;

[0059] S2: The recycled fiber material, foaming agent, water-soluble polymer, cross-linking agent, flame retardant, biomass filler and water are mixed in sequence and crushed and stirred at 35,000 rpm for 3 minutes to obtain cellulose pulp foam;

[0060] S3: sieve the cellulose pulp foam, drain the water, let it stand for 30 minutes and put it into a mold to set;

[0061] S4: Blast drying at 80°C for 12 hours to obtain a biomass foam thermal insulation and fireproof heat preservation material.

[0062] The preparation method of the recycled fiber material comprises the following steps: removing impurities from paper products, and crushing at 32,000 rpm for 1 minute to obtain the recycled fiber material.

[0063] If the raw materials for the preparation of Examples 1-16 do not contain water-soluble polymers, cross-linking agents, flame retardants, and biomass fillers, they will not be added in the preparation method.

[0064] The flow chart of the biomass foam thermal insulation and fireproofing material prepared in Example 19 is shown in FIG. Figure 1 .

[0065] Performance Testing

[0066] 1. Foam performance test: See the actual photos of Examples 1-19 Figure 2-6 The foam of the biomass foam thermal insulation and fireproofing material prepared in Example 5 had already collapsed, so drying was unnecessary. Therefore, no photos of the material after drying are available. Foam density = weight of the material prepared in Example 5 / volume of the material prepared in Example 5. See Table 2 for test results.

[0067] Table 2

[0068] Foaming rate / % <![CDATA[Foam density (kg / m 3 )]]> Example 3 95 17.80 Example 8 95 18.30 Example 9 95 18.60 Example 11 85 25.80 Example 12 90 21.00 Example 13 95 18.60 Example 15 95 27.00 Example 19 95 28.50

[0069] 2. Water resistance test: Immerse the biomass foam thermal insulation and fireproofing materials (2g) prepared in Example 3, Example 11, Example 12, and Example 13 in distilled water (20g) at 25°C for 0 days, 3 days, 5 days, 10 days, and 25 days, and take pictures to check their appearance in water. Figure 7 .

[0070] Depend on Figure 7 It can be seen that Example 3, which does not contain a crosslinking agent component, completely dispersed in water after 3 days. Examples 11, 12, and 13 contain 0.5, 0.3, and 0.1 parts by weight of a crosslinking agent component, respectively. It can be seen that Example 13, when containing 0.1 parts by weight of a crosslinking agent, effectively prevents the biomass foam thermal insulation and fireproofing material from dispersing in water, with only a small amount of fibers scattered at the bottom of the water. When containing 0.3 and 0.5 parts by weight of a crosslinking agent, only a very small amount of scattered fibers is observed.

[0071] 3. Soil degradation test: The biomass foam thermal insulation and fireproofing materials (5g) prepared in Example 3, Example 15, and Example 19 were buried in standardized soil at a depth of 5cm, maintaining a humidity of 40%-60% and a temperature of 25°C. After 0 days, 15 days, and 30 days of testing, photos were taken to check the status. The test results are shown in Figure 8 .

[0072] Depend on Figure 8As can be seen, Example 3, which lacks sodium carboxymethylcellulose (physical crosslinking) and polyamide-epichlorohydrin (chemical crosslinking), exhibits the fastest apparent degradation rate, with soil degradation reaching 70% in 30 days. Examples 15 and 19, while incorporating sodium carboxymethylcellulose and polyamide-epichlorohydrin, gradually introduce clay and ammonium polyphosphate. The soil degradation rates of Examples 15 and 19 are significantly slower than that of Example 3, which lacks a crosslinking agent. The biomass foam insulation and fireproofing properties of Example 19 will degrade completely over time.

[0073] 4. Thermal insulation test: Place the sample between a heat source and a cold source and record the temperature gradient and heat flow. The sample thickness should be uniform and the test environment should avoid air convection interference. Figure 10 , 11.

[0074] Figure 11 This is a comparative test of the thermal insulation performance of Example 19 and polystyrene foam (XPS). The foam samples were heated continuously for 30 minutes on a constant temperature hot plate. The temperature was measured every 5 minutes at different locations on the side of the foam sample (a, b, c) and the top center location (d). Figure 10 Comparison of infrared photos of polystyrene foam (XPS) and Example 19 after heating for 30 minutes shows that the thermal insulation performance of Example 19 prepared in the laboratory is more stable and uniform; Figure 11 The temperature / time curve of Example 19 shows more excellent thermal insulation performance.

[0075] 5. Flame retardant performance test: refer to standard UL 94, ignite the biomass foam thermal insulation fireproof thermal insulation materials prepared in Examples 1, 15, and 19, and record the burning time, spread speed, and whether it self-extinguishes. Figure 9 Example 1 does not contain fireproof filler. In Example 19, clay and ammonium polyphosphate are added as fireproof components. Figure 9 As can be seen, after Example 1 was ignited, although the flame did not sustain combustion, the sample continued to smolder, releasing smoke and heat until the sample was completely burned out. Example 19 could not be ignited and quickly extinguished naturally, demonstrating excellent fire retardant effects. Example 15, even without the presence of a flame retardant, also could not be ignited and still maintained a good flame retardant effect.

Claims

1. A biodegradable biomass foam thermal insulation and fireproofing material, characterized in that: The raw materials for preparation include, by weight: 1-10 parts of recycled fiber material, 0.1-2 parts of foaming agent, and 190-200 parts of water; the raw materials for preparation also include water-soluble polymer, cross-linking agent, flame retardant, and biomass filler.

2. The biodegradable biomass foam thermal insulation and fireproofing material according to claim 1, characterized in that: The flame retardant is a phosphorus-based flame retardant, and the added amount of the flame retardant is 0.5-2 parts by weight.

3. The biodegradable biomass foam thermal insulation and fireproofing material according to claim 2, characterized in that: The phosphorus-based flame retardant includes at least one of ammonium polyphosphate, aluminum hypophosphite, melamine phosphate, red phosphorus, polyphosphonate or hydroxyapatite.

4. The biodegradable biomass foam thermal insulation and fireproofing material according to claim 1, characterized in that: The biomass filler includes at least one of clay, attapulgite, kaolin, lignin, starch, chitosan, protein-based filler or biochar, and the added amount of the biomass filler is 2-8 parts by weight.

5. The biodegradable biomass foam thermal insulation and fireproofing material according to claim 1, characterized in that: The added amount of the cross-linking agent is 0.1-0.5 parts by weight.

6. The biodegradable biomass foam thermal insulation and fireproofing material according to claim 5, characterized in that: The crosslinking agent includes at least one of a nitrogen-containing polymer crosslinking agent, a carboxylic acid crosslinking agent, a polyphenol crosslinking agent, an aldehyde crosslinking agent or an epoxy polymer crosslinking agent.

7. The biodegradable biomass foam thermal insulation and fireproofing material according to claim 1, characterized in that: The water-soluble polymer includes at least one of carboxymethyl cellulose salt, hydroxy cellulose, methyl cellulose, guar gum, gum arabic, hydroxypropyl methyl cellulose, sodium alginate, sodium polyacrylate or ethyl cellulose, and the added amount of the water-soluble polymer is 0.2-0.5 parts by weight.

8. The biodegradable biomass foam thermal insulation and fireproofing material according to claim 1, characterized in that: The foaming agent is at least one of an anionic surfactant, a zwitterionic surfactant or a nonionic surfactant, and the HLB value of the foaming agent is 15-40.

9. The biodegradable biomass foam thermal insulation and fireproofing material according to claim 8, characterized in that: The recycled fiber material is a cellulose material prepared by crushing paper products.

10. A method for preparing the degradable biomass foam thermal insulation and fireproofing material according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1: Preparation of recycled fiber material; S2: sequentially mixing the recycled fiber material, foaming agent, water-soluble polymer, cross-linking agent, flame retardant, biomass filler and water and stirring at 3000-4000 rpm for 1-5 minutes to obtain cellulose pulp foam; S3: placing the cellulose pulp foam into a mesh mold and letting it stand, drain, and set; S4: Drying at 70-90° C. for 10-15 hours to obtain a biomass foam thermal insulation and fireproof heat preservation material.

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