Mycelium synthetic material processing technology

Abstract

The invention discloses a mycelium synthetic material processing technology. The process comprises the following steps: carrying out thermal pretreatment on a wet mycelium substrate; an alkaline activated precursor emulsion containing sodium lignin sulfonate and epoxidized soybean oil is infiltrated into the mycelium matrix by using vacuum pulse; then immersing into an acidic phase transformation locking solution containing metal salt, inducing sodium lignin sulfonate to be separated out in situ in pores of the mycelium matrix by utilizing pH gradient, and finishing coordination locking by utilizing metal ions; and after washing and pre-drying, gradient hot-pressing curing is carried out. Deep filling of modified components is achieved through acid-base phase conversion, residual metal ions serve as Lewis acid to catalyze ring opening polymerization of epoxy bonds, and a metal coordination and covalent crosslinking coexisting interpenetrating polymer network is constructed in the material. The obtained material has high density, high static bending intensity and excellent water-resistant stability, and the problems that a traditional mycelium material is loose in structure and poor in mechanical property are solved.

Description

Technical Field

[0001] This invention relates to the field of biomass composite material manufacturing technology, specifically a mycelium synthesis material processing technology. Background Technology

[0002] With increasing emphasis on sustainable development and environmental protection, biomass materials that utilize fungal mycelium to degrade agricultural waste and self-assemble into shapes are considered potential alternatives to traditional foam plastics and some wood-based panels due to their advantages such as complete biodegradability, low carbon footprint, and wide availability of raw materials.

[0003] However, naturally grown mycelial materials face significant performance bottlenecks in practical applications. Since mycelia are primarily composed of micron-sized tubular hyphae that extend and branch from their tips, their microstructure exhibits a loose and porous state, resulting in low overall density and high porosity. This loosely packed structure leads to poor mechanical strength and insufficient rigidity in unmodified mycelial materials, making it difficult to meet the structural load-bearing requirements of furniture components or building decoration materials.

[0004] Furthermore, the cell walls of mycelium are mainly composed of chitin, dextran, and other polysaccharides, as well as proteins. These components are rich in hydrophilic groups such as hydroxyl and amino groups. This makes the mycelial material extremely sensitive to moisture, easily absorbing moisture and swelling in humid environments. This not only leads to a decrease in the material's dimensional stability but also causes a sharp decline in mechanical properties and may even induce the growth of other microorganisms, resulting in material decay.

[0005] In existing technologies, physical hot pressing densification or the addition of adhesives are commonly used to improve the performance of mycelial materials. While simple physical hot pressing can increase density to some extent, the lack of internal intermolecular chemical bonds makes the material prone to stress release and thickness rebound after moisture absorption. Introducing traditional petroleum-based adhesives such as urea-formaldehyde resin, phenolic resin, or isocyanates can significantly improve mechanical strength and water resistance, but often introduces volatile organic compounds and undermines the fully biodegradable and environmentally friendly characteristics of the mycelial material. Currently, a process method is lacking that can deeply fill microporous defects within the matrix while simultaneously constructing an efficient chemical cross-linking network to improve the material's density and water resistance. Summary of the Invention

[0006] The technical problem solved by this invention is that existing synthetic materials made from fungal mycelia such as Ganoderma lucidum generally have a loose internal mycelial network structure, high porosity, and strong hydrophilicity, resulting in low material density, insufficient mechanical strength, and poor water resistance, making it difficult to meet the requirements of high-strength structural components or humid environments.

[0007] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a processing technology for mycelial synthetic materials, which adopts the following technical solution: A process for processing mycelium synthetic materials includes the following steps: S1. Substrate pretreatment: The wet mycelial substrate is heat-treated at 70℃~80℃, and the moisture content of the mycelial substrate after treatment is controlled to be 40%~50%; S2, Vacuum Pulse Permeation and Activation: The mycelial matrix treated in S1 is placed in a vacuum environment, and the pore air is discharged under a negative pressure of -0.08MPa to -0.095MPa. Then, an alkaline activation precursor emulsion is drawn in until the mycelial matrix is ​​submerged. The pressure is then restored to normal or a positive pressure of 0.2MPa to 0.4MPa is applied for impregnation. The mycelium is swollen and deacetylated in a strongly alkaline environment. The alkaline activation precursor emulsion is made from the following raw materials in parts by weight: based on 100 parts of deionized water, it contains 10 to 20 parts of sodium lignosulfonate and 5 to 10 parts of epoxidized soybean oil, and the pH value of the emulsion is adjusted to 11.5 to 13.0 by adding an alkali regulator. S3, Acidic Impact Phase Separation and Locking: The mycelial matrix impregnated in S2 is drained and immersed in an acidic phase inversion locking solution for treatment. The acidic environment and the alkalinity inside the mycelial matrix induce the in-situ precipitation of sodium lignin sulfonate and complete the coordination locking of metal ions. The acidic phase inversion locking solution is an aqueous solution containing metal salts with a concentration of 0.5 mol / L to 1.5 mol / L, and the pH value of the solution is adjusted to 1.0 to 2.5 by adding an acid adjuster. S4. Washing and pre-drying: Wash the mycelial matrix after S3 treatment with water until the effluent is neutral to remove free ions. Then pre-dry it at 50℃~60℃, and control the moisture content of the mycelial matrix to 15%~20% to prevent steam defects during subsequent hot pressing. S5. Gradient hot-press curing: The mycelial matrix treated with S4 is placed in a mold for two-stage hot-press curing: the first stage temperature is 95℃~105℃ and the pressure is 2.0MPa~4.0MPa; the second stage temperature is 140℃~160℃ and the pressure is 8.0MPa~12.0MPa.

[0008] By employing the above technical solution, this invention utilizes pH gradient-induced in-situ precipitation and metal-catalyzed crosslinking to improve the density and mechanical properties of the material. The specific principle is as follows: First, in step S2, the strongly alkaline environment of pH 11.5–13.0 induces swelling of chitin fibers in the mycelial cell walls and triggers partial deacetylation to generate chitosan, increasing the exposure of active amino and hydroxyl groups. This process expands the micropore size of the mycelial matrix, and combined with vacuum negative pressure and positive pressure pulse technology, allows high molecular weight sodium lignin sulfonate and hydrophobic epoxidized soybean oil to effectively penetrate into the three-dimensional network inside the mycelium.

[0009] Secondly, in step S3, when the mycelial matrix filled with alkaline precursor solution is immersed in a strongly acidic solution with a pH of 1.0–2.5, a rapid acid-base neutralization reaction occurs inside the mycelial matrix. The solubility of sodium lignin sulfonate decreases sharply under acidic conditions, forcing the sodium lignin sulfonate that has penetrated the micropores to precipitate in situ and separate from the dissolved state, transforming into an insoluble solid, precipitating and filling the gaps between the mycelial fibers. This in-situ precipitated filler supports the pore structure and reduces pore collapse caused by moisture evaporation during drying.

[0010] Furthermore, in steps S3 and S4, the high concentration of metal cations, including aluminum or iron ions, in the acidic phase inversion solution diffuses into the mycelial matrix, forming stable coordination structures with the sulfonic acid groups of sodium lignosulfonate and the amino groups generated by mycelial deacetylation. This multi-site coordination fixes the filler and mycelial fibers, restricts the movement of polymer chains, and reduces component loss during the washing process. Simultaneously, the pre-drying in step S4 precisely controls the moisture content, preventing steam defects caused by high moisture content during high-temperature mold closing and thus preventing delamination of the board.

[0011] Finally, during the hot pressing process in step S5, the metal ions remaining inside the mycelial matrix are converted into Lewis acid catalysts. Under high temperature and high pressure conditions, the metal ions lower the activation energy of the ring-opening polymerization of epoxy bonds in epoxidized soybean oil, catalyzing the chemical grafting and cross-linking reactions between epoxy groups and the hydroxyl and amino groups on mycelial fibers and lignin molecules. Ultimately, an interpenetrating polymer network consisting of a metal coordination network and an epoxy covalent cross-linked network is constructed inside the material, significantly improving the material's water resistance and mechanical strength.

[0012] Preferably, the preparation method of the alkaline activated precursor emulsion in S2 is as follows: sodium lignosulfonate is dissolved in deionized water, sodium hydroxide aqueous solution is added dropwise to adjust the pH value to 11.5-13.0, then epoxidized soybean oil is added, and the mixture is sheared and homogenized at 5,000-8,000 rpm for 5-10 minutes using a high-shear dispersing emulsifier to obtain an oil-in-water (O / W) emulsion. By adopting the above technical solution, sodium lignosulfonate plays the role of an amphiphilic surfactant, emulsifying and dispersing the hydrophobic epoxidized soybean oil in the aqueous phase under high shear force to form a stable and homogeneous emulsion, ensuring that the two modified components can simultaneously penetrate into the hydrophilic mycelial matrix.

[0013] Preferably, the metal salt in the acidic phase inversion locking solution in S3 is selected from aluminum chloride hexahydrate or anhydrous ferric chloride; the acid regulator is hydrochloric acid. By adopting the above technical solution, aluminum ions or iron ions not only have high coordination constants and can form stable cross-linked structures, but also, as typical Lewis acids, have catalytic activity for epoxy ring-opening polymerization.

[0014] Preferably, the method for preparing the wet mycelial matrix in S1 is as follows: using Ganoderma lucidum as the strain to produce mycelium, using lignocellulose waste with a particle size of 1.0 mm to 3.0 mm as the culture substrate, and culturing at 25°C in the dark until the mycelium completely covers the mycelial matrix, finally obtaining a wet mycelial matrix with an initial moisture content of 50% to 70%.

[0015] Preferably, in S2, the total immersion time for vacuum pulse penetration and activation is 30 to 60 minutes; in S3, the treatment method for acidic impact phase separation and locking is immersion or spraying, and the treatment time is 15 to 30 minutes.

[0016] Preferably, in step S5, the first stage hot pressing time is 5-10 minutes, the second stage hot pressing time is 10-20 minutes, and after hot pressing, the pressure is maintained and cooled to below 60°C for demolding. By adopting the above technical solution, the staged hot pressing process first utilizes metal ions to catalyze epoxy prepolymerization at a lower temperature to establish a preliminary network and reduce component loss at high temperatures; subsequently, under high temperature and high pressure, lignin undergoes thermoplastic rheology and deep curing, reducing internal defects and increasing density.

[0017] Preferably, the sodium lignosulfonate has a weight-average molecular weight of 8,000 Da to 15,000 Da and a sulfonation degree of 1.5 mmol / g to 2.5 mmol / g; the epoxidized soybean oil has an epoxy value ≥ 6.0% and a viscosity of 300 cP to 500 cP. .

[0018] Secondly, the present invention provides a mycelium synthetic material prepared using the above-described process, employing the following technical solution: A mycelium synthetic material, said material being prepared by chemical modification and hot-press curing of raw materials comprising the following components: Mycelial substrate; The modified component is derived from the reaction product of the above-mentioned alkaline activated precursor emulsion and acidic phase inversion locking solution. The modified components include sodium lignosulfonate crosslinker, ring-opening cured epoxidized soybean oil, and metal ion ligands. Furthermore, during the preparation process, based on 100 parts by weight of deionized water, the amount of sodium lignosulfonate is 10-20 parts, and the amount of epoxidized soybean oil is 5-10 parts.

[0019] By adopting the above technical solution, the resulting material improves upon the problem of weak interfacial bonding in traditional physical blending modification. The components within the material form a stable bonded state through chemical bonding.

[0020] Preferably, the material has an interpenetrating polymer network structure, wherein the amino groups on the surface of the mycelium fibers, the sulfonic acid groups of sodium lignin sulfonate, and the metal ions form coordination crosslinks, and the epoxidized soybean oil forms covalent crosslinks with the active groups of the mycelium and lignin; the gel content of the material is greater than 90%.

[0021] By adopting the above technical solution, the high gel content indicates that a high-density cross-linked network has been formed inside the material, which improves the solvent resistance and dimensional stability of the material, making it less prone to swelling and deformation in humid environments.

[0022] Preferably, the material has a density of 1.25 g / cm³ to 1.40 g / cm³, a 24-hour water absorption thickness expansion rate of less than 5%, and a static bending strength greater than 40 MPa. By adopting the above technical solution, the physical performance indicators of this material meet the relevant requirements of high-density fiberboard, making it feasible for high-density fiberboard to replace some traditional wood-based panels in furniture manufacturing, building decoration, and structural support components.

[0023] This invention provides a processing technology for mycelial synthetic materials. It has the following beneficial effects: 1. This invention utilizes a pH gradient-induced in-situ precipitation process to significantly improve the density and mechanical strength of mycelial materials. Through swelling in a strongly alkaline environment, sodium lignosulfonate and epoxidized soybean oil can penetrate deep into the mycelial fibers. Subsequently, the instantaneous neutralization effect of the acidic environment forces sodium lignosulfonate to transform into an insoluble state and precipitate in situ within the micropores of the mycelial matrix. This filling effect effectively supports the three-dimensional network framework of the mycelium, reduces pore collapse during drying, and solves the technical problem of loose internal structure and low load-bearing capacity in natural mycelial materials.

[0024] 2. This invention constructs an interpenetrating polymer network with both coordination and covalent bonds, significantly improving the material's water resistance and dimensional stability. The introduced aluminum or iron ions form multi-site coordination crosslinks with lignin sulfonate and mycelial amino groups, restricting the freedom of hydrophilic groups. Furthermore, they act as Lewis acid catalysts, efficiently catalyzing the ring-opening polymerization of epoxidized soybean oil during hot pressing, and forming covalent grafts with the mycelial matrix. This high-density, dual-crosslinked network hinders the invasion and penetration of water molecules, enabling the material to maintain a low water absorption thickness swelling rate even in humid environments.

[0025] 3. This invention achieves highly efficient synergistic curing of all biomass components, reaching the performance indicators of high-density fiberboard without the use of formaldehyde-based adhesives. The sodium lignosulfonate used in the process functions as both a dispersant and a reinforcing filler, while epoxidized soybean oil acts as both a plasticizer and a crosslinking agent. Both undergo phase separation, fixation, and thermosetting reactions under the regulation of metal ions. The resulting composite material exhibits high static bending strength and elastic modulus, as well as high surface hardness, making it a practical alternative to traditional wood-based panels in furniture manufacturing and interior building applications. Attached Figure Description

[0026] Figure 1 This is a process flow diagram of the present invention. Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] The main raw materials and reagents used in the following examples and comparative examples have the following sources and specifications. Reagents not specifically mentioned are all commercially available analytical grade or higher grade products.

[0029] The Ganoderma lucidum mycelium substrate is made from Ganoderma lucidum spores. The substrate is composed of oak sawdust and cottonseed hulls in a mass ratio of 80:20. The particle size of the substrate is selected from 1.0 mm to 3.0 mm. After high-temperature sterilization and inoculation, it is cultured at 25°C in the dark for 30 days until the mycelium completely covers the substrate. Before use, it should be kept moist with a moisture content of 50% to 70%.

[0030] Sodium lignosulfonate, CAS No. 8061-51-6, industrial grade, with a weight-average molecular weight (Mw) of 8000 Da to 15000 Da and a degree of sulfonation of 1.5 mmol / g to 2.5 mmol / g.

[0031] Epoxidized soybean oil, CAS No. 8013-07-8, epoxy value ≥6.0%, viscosity (25℃) is 300cP~500cP.

[0032] Aluminum chloride hexahydrate, CAS No. 7784-13-6, analytical grade, purity ≥97.0%.

[0033] Anhydrous ferric chloride, CAS No. 7705-08-0, analytical grade, purity ≥98.0%.

[0034] Sodium hydroxide, CAS No. 1310-73-2, analytical grade, purity ≥96.0%.

[0035] Preparation Example 1: This preparation example provides an alkaline activated precursor emulsion (component A) for verifying low concentration / low alkalinity conditions, including the following steps: Take 100 parts by weight of deionized water, add 10 parts by weight of sodium lignosulfonate, and stir at 300 rpm at room temperature to dissolve; add 2 mol / L sodium hydroxide aqueous solution to the solution to adjust the pH value to 11.5; while maintaining stirring, add 5 parts by weight of epoxidized soybean oil, and use a high shear dispersion emulsifier to shear homogenize at 5000 rpm for 5 minutes to obtain a brownish-brown homogeneous emulsion, labeled A1 for later use.

[0036] Preparation Example 2: This preparation example provides an alkaline activated precursor emulsion (component A) for the preferred embodiment, comprising the following steps: Take 100 parts by weight of deionized water, add 15 parts by weight of sodium lignosulfonate, and stir at 400 rpm at room temperature to dissolve; add 2 mol / L sodium hydroxide aqueous solution dropwise to the solution to adjust the pH value of the solution to 12.5; while maintaining stirring, add 8 parts by weight of epoxidized soybean oil, and use a high-shear dispersing emulsifier to shear homogenize at 6000 rpm for 8 minutes to obtain a brownish-brown homogeneous emulsion, labeled A2 for later use.

[0037] Preparation Example 3: This preparation example provides an alkaline activated precursor emulsion (component A) for verifying high concentration / high alkalinity conditions, including the following steps: Take 100 parts by weight of deionized water, add 20 parts by weight of sodium lignosulfonate, and stir at 500 rpm at room temperature to dissolve; add 5 mol / L sodium hydroxide aqueous solution to the solution to adjust the pH value to 13.0; while maintaining stirring, add 10 parts by weight of epoxidized soybean oil, and use a high shear dispersion emulsifier to shear homogenize at 8000 rpm for 10 minutes to obtain a brownish-brown homogeneous emulsion, labeled A3 for later use.

[0038] Preparation Example 4: This preparation example provides a neutral comparative precursor emulsion (comparative component A) to verify the necessity of a pH gradient, including the following steps: Take 100 parts by weight of deionized water, add 15 parts by weight of sodium lignosulfonate, and stir to dissolve at room temperature; without strong alkali adjustment, only add a trace amount of dilute sodium hydroxide solution to adjust the pH value to 7.5 (neutral environment); add 8 parts by weight of epoxidized soybean oil, and use a high-shear dispersing emulsifier to shear homogenize at 6000 rpm for 8 minutes to obtain the comparative emulsion, labeled A4 for later use.

[0039] Preparation Example 5: This preparation example provides an acidic phase inversion locking solution (component B) for verifying low concentration / low acidity conditions, including the following steps: Weigh aluminum chloride hexahydrate and dissolve it in deionized water to prepare a solution with a concentration of 0.5 mol / L; adjust the pH of the solution to 2.5 using hydrochloric acid to obtain a colorless and transparent solution, labeled as B1 for later use.

[0040] Preparation Example 6: This preparation example provides an acidic phase inversion locking solution (component B) for the best implementation, comprising the following steps: weighing aluminum chloride hexahydrate and dissolving it in deionized water to prepare a solution with a concentration of 1.0 mol / L; adjusting the pH of the solution to 2.0 using hydrochloric acid to obtain a colorless and transparent solution, labeled as B2 for later use.

[0041] Preparation Example 7: This preparation example provides an acidic phase inversion locking solution (component B) for verifying high concentration / high acidity conditions, including the following steps: Weigh aluminum chloride hexahydrate and dissolve it in deionized water to prepare a solution with a concentration of 1.5 mol / L; adjust the pH of the solution to 1.0 using hydrochloric acid to obtain a colorless and transparent solution, labeled as B3 for later use.

[0042] Preparation Example 8: This preparation example provides an iron-based acidic phase inversion locking solution (component B) for verifying the substitutability of metal ions, including the following steps: weigh anhydrous ferric chloride and dissolve it in deionized water to prepare a solution with a concentration of 1.0 mol / L; adjust the pH of the solution to 1.5 using hydrochloric acid to obtain a reddish-brown transparent solution, labeled as B4 for later use.

[0043] Preparation Example 9: This preparation example provides a metal-free acidic solution (comparative component B) for verifying the necessity of metal coordination, including the following steps: take deionized water, add only hydrochloric acid to adjust the pH to 2.0, without adding any metal salts, and label it as B5 for later use.

[0044] Example 1: This embodiment provides a processing technology for mycelium synthetic materials, including the following steps: Step 1: Substrate pretreatment: Place the wet Ganoderma lucidum mycelium substrate in a 75°C forced-air drying oven for 30 minutes to partially dehydrate and inactivate the Ganoderma lucidum mycelium, controlling the moisture content of the mycelium substrate to be around 45%.

[0045] Step 2, Vacuum Pulse Infiltration and Activation: The pretreated mycelial matrix is ​​placed in a vacuum impregnation vessel, and a vacuum is drawn to -0.09 MPa and maintained for 10 minutes; the alkaline activated precursor emulsion (A2) obtained in Example 2 is drawn in under negative pressure until the mycelial matrix is ​​completely submerged; normal pressure is restored and a positive pressure of 0.3 MPa is applied, and impregnation is maintained for 45 minutes to swell and activate the mycelial fibers in a strongly alkaline environment (pH 12.5).

[0046] Step 3, acidic shock phase inversion: Take out the mycelial matrix and drain it for 2 minutes. Immediately immerse it in the acidic phase inversion locking solution (B2) obtained in Preparation Example 6 and soak it for 20 minutes. The acid-base neutralization reaction (pH 12.5→2.0) forces the infiltrated sodium lignin sulfonate to precipitate in situ in the pores of the mycelial matrix, while aluminum ions are used to complete the coordination locking.

[0047] Step 4, Pre-drying: Take out the mycelial substrate, wash it with water until the effluent is neutral, and dry it at 55°C until the moisture content is about 18%.

[0048] Step 5, Gradient hot pressing curing: The mycelium matrix is ​​placed in a metal mold and first hot-pressed at 100℃ and 3.0MPa for 8 minutes to utilize the residual metal ions to catalyze the ring-opening polymerization of epoxy; then the temperature is raised to 150℃ and the pressure is increased to 10.0MPa, and held for 15 minutes to allow lignin rheology and complete deep cross-linking; after cooling to below 60℃, the high-density mycelium composite material is obtained.

[0049] Example 2: This embodiment provides a processing technology for mycelial synthetic materials (verification under low parameter / low alkalinity conditions), including the following steps: Step 1, Substrate Pretreatment: Treat the wet mycelial substrate at 70℃ for 20 minutes, controlling the moisture content to 50%.

[0050] Step 2, Vacuum Pulse Infiltration and Activation: Place the mycelial matrix in a vacuum vessel and evacuate to -0.08 MPa for 10 minutes; aspirate the alkaline activated precursor emulsion (A1) obtained in Preparation Example 1 to submerge the mycelial matrix; restore normal pressure (without applying positive pressure) and maintain immersion for 30 minutes.

[0051] Step 3, acidic shock phase inversion: Remove the mycelial substrate, drain it, and immediately immerse it in the acidic phase inversion locking solution (B1) obtained in Preparation Example 5 for 15 minutes.

[0052] Step 4: Pre-drying: After washing with water, dry at 50℃ until the moisture content is about 20%.

[0053] Step 5, Gradient hot pressing curing: First stage hot pressing temperature 95℃, pressure 2.0MPa, time 10 minutes; Second stage hot pressing temperature 140℃, pressure 8.0MPa, time 10 minutes; Cool and demold.

[0054] Example 3: This embodiment provides a processing technology for mycelial synthetic materials (validation under high parameters / high alkalinity conditions), including the following steps: Step 1, Substrate Pretreatment: Treat the wet mycelial substrate at 80℃ for 40 minutes, controlling the moisture content to 40%.

[0055] Step 2, Vacuum Pulse Infiltration and Activation: Place the mycelial matrix in a vacuum vessel and evacuate to -0.095 MPa for 15 minutes; aspirate the alkaline activated precursor emulsion (A3) obtained in Preparation Example 3 to submerge the mycelial matrix; restore normal pressure and apply a positive pressure of 0.4 MPa, maintaining immersion for 60 minutes to achieve maximum swelling and component loading.

[0056] Step 3, acid shock phase inversion: The mycelial substrate was removed and drained, and immediately immersed in the acidic phase inversion locking solution (B3) obtained in Preparation Example 7 for 30 minutes. The strong acid shock (pH 1.0) was used to achieve rapid and deep phase separation and fixation.

[0057] Step 4: Pre-drying: After washing with water, dry at 60℃ until the moisture content is about 15%.

[0058] Step 5, Gradient hot pressing curing: First stage hot pressing temperature 105℃, pressure 4.0MPa, time 5 minutes; Second stage hot pressing temperature 160℃, pressure 12.0MPa, time 20 minutes; Cool and demold.

[0059] Example 4: This embodiment provides a processing technology for mycelium synthetic materials (verification of iron-based metal ion substitution), including the following steps: Step 1, matrix pretreatment: Same as in Example 1.

[0060] Step 2, Vacuum pulse permeation and activation: The alkaline activated precursor emulsion (A2) obtained in Preparation Example 2 was used, and the process parameters were the same as in Example 1.

[0061] Step 3, acidic shock phase inversion: The mycelial matrix was removed and drained, and immediately immersed in the iron-based acidic phase inversion locking solution (B4) obtained in Preparation Example 8 for 20 minutes; iron ions were used to replace aluminum ions for coordination crosslinking, at which point the mycelial matrix turned dark reddish-brown.

[0062] Step 4, Pre-drying: Same as in Example 1.

[0063] Step 5, Gradient hot pressing curing: First stage hot pressing temperature 100℃, pressure 3.0MPa, time 8 minutes; Second stage hot pressing temperature 150℃, pressure 10.0MPa, time 15 minutes; Cool and demold, the resulting material has a deep natural color and high hardness.

[0064] Example 5: This embodiment provides a processing technology for mycelium synthetic materials (verification of long-term curing process), including the following steps: Step 1, matrix pretreatment: Same as in Example 1.

[0065] Step 2, Vacuum Pulse Permeation and Activation: The alkaline activated precursor emulsion (A2) obtained in Preparation Example 2 was used, but the immersion time was extended to 90 minutes to verify the ultimate permeation effect.

[0066] Step 3, Acidic shock phase inversion: Immerse the sample in the acidic phase inversion locking solution (B2) obtained in Preparation Example 6 for 25 minutes.

[0067] Step 4, Pre-drying: Same as in Example 1.

[0068] Step 5, Gradient hot pressing curing: Adjust the hot pressing curve. In the first stage, maintain 100℃ and 3.0MPa for 15 minutes (extend the catalytic reaction time); in the second stage, maintain 145℃ and 11.0MPa for 25 minutes (extend the densification time); cool and demold.

[0069] The following are comparative examples designed to comprehensively highlight the technical advantages of this invention. These comparative examples are designed to compare aspects such as pH gradient effects, metal coordination catalysis, and the necessity of each component.

[0070] Comparative Example 1: Compared with Example 1, the difference is that the impregnation solution used in step 2 was replaced with the neutral comparative precursor emulsion (A4) obtained in Preparation Example 4, and the treatment solution used in step 3 was a 1.0 mol / L aluminum chloride aqueous solution without hydrochloric acid pH adjustment (natural pH value is about 3.5). The pH change environment of "strong base swelling - strong acid shock" was not constructed in the entire process, and the remaining steps were the same as in Example 1.

[0071] Comparative Example 2: Compared with Example 1, the difference is that the treatment solution used in step 3 was replaced with the metal-free comparative acidic solution (B5) obtained in Preparation Example 9, and metal ions were absent during the treatment process. It participates in coordination crosslinking and catalytic reactions, and the remaining steps are the same as in Example 1.

[0072] Comparative Example 3: Compared with Example 1, the difference is that the alkaline activated precursor emulsion used in step 2 does not contain epoxidized soybean oil (ESO) during the preparation process, and only sodium lignosulfonate is retained as the single modifying component. The remaining steps are the same as in Example 1.

[0073] Comparative Example 4: Compared with Example 1, the difference is that sodium lignosulfonate (SLS) is not added to the alkaline activated precursor emulsion used in step 2 during the preparation process. Instead, an equal amount of conventional emulsifier (such as Tween-80) is added to stabilize the epoxidized soybean oil emulsion. The mycelial matrix lacks rigid skeleton filling. The remaining steps are the same as in Example 1.

[0074] Comparative Example 5: Compared with Example 1, the difference is that steps 2 (vacuum pulse penetration and activation) and 3 (acidic shock phase inversion) are completely omitted. The mycelial matrix pretreated in step 1 is directly dried in step 4 (to a moisture content of 18%) and cured by gradient hot pressing in step 5. That is, conventional physical hot pressing process is used. The other conditions are the same as in Example 1.

[0075] Test Example 1: Reaction Mechanism Characterization and Crosslinking Degree Test Experimental instructions The board samples prepared in Examples 1, 4, 1, 2 and 5 were selected, and the occurrence of chemical reactions and the density of the network structure were determined by infrared spectroscopy and solvent extraction.

[0076] First, Fourier transform infrared spectroscopy (FT-IR) analysis was performed. The sample to be tested was pulverized and passed through a 200-mesh sieve. Approximately 1 mg of the powder sample was mixed with 100 mg of dry potassium bromide (KBr) powder, ground, and compressed into a tablet. FT-IR spectroscopy was then used to analyze the sample. to Scan within the wavenumber range, with resolution set to [value missing]. A total of 32 scans were conducted. Key observations were conducted. Characteristic absorption peaks of epoxy groups at the location, The absorption peaks of hydroxyl and amino complexes at the position and The carbonyl absorption peak at [location]. This is a vibrational peak representing the benzene ring skeleton. As an internal standard, calculations were performed before and after curing. The change in absorbance was observed, and the conversion rate of the epoxy groups was then determined.

[0077] Subsequently, a gel content test was performed. The sample to be tested was cut into particles, and the mass was measured. Approximately 2.0 g of the sample was wrapped in filter paper and placed in a Soxhlet extractor. Acetone was used as the solvent, and the sample was refluxed in an 80°C water bath for 24 hours to remove unreacted free components and small molecule impurities. After extraction, the sample was removed and dried in a 105°C oven to constant weight. The residue was then weighed. The formula for calculating gel content is: .

[0078] Conclusions and Analysis

[0079] Infrared spectral data and Table 4 show that the epoxy group conversion rates of Examples 1 and 4 both exceeded 92%, and the gel content was higher than 91%. In the spectra, the sample from the examples... The epoxy characteristic peaks at the location have essentially disappeared, indicating that in Lewis acid... Under catalysis, epoxidized soybean oil underwent ring-opening polymerization and formed covalent bonds with the hydroxyl and amino groups on the mycelium and lignin. Simultaneously, The low wavenumber shift and broadening of the carbonyl absorption peak indicate that coordinate bonds have formed between the metal cation, lignin sulfonate, and chitosan amino groups. The coexistence of covalent and coordinate bonds constitutes an interpenetrating network structure.

[0080] Comparative Example 1 had a gel content of 28.45% and a low epoxy conversion rate. This group lacked a pH gradient environment, making it difficult for the modifier to penetrate deep into the mycelial matrix. Furthermore, sodium lignin sulfonate did not precipitate in situ and migrated with moisture during drying, failing to form an effective internal framework. Due to the lack of an acidic environment for activation, the epoxidized soybean oil existed mostly in a free state and was removed during solvent extraction.

[0081] The gel content of Comparative Example 2 was 62.14%, higher than Comparative Example 1 but lower than that of the Example Group. Although this group had an acidic environment that precipitated lignin, it lacked metal ions. The data reflects that the physical packing strength of lignin precipitated by simple acid precipitation is limited, and the lack of metal Lewis acid catalysis restricts the ring-opening reaction kinetics of the epoxy groups, resulting in a conversion rate of only 56.89%. This confirms that metal ions play a dual role in the system, acting as both coordination crosslinkers and catalytic curing agents.

[0082] Comparative Example 5, used as a physical hot-pressing control, showed a residual rate of 14.33%, originating from the chitin and cellulose components of the mycelium itself, lacking a chemically cross-linked network. These results indicate that pH gradient-induced in-situ phase separation and metal ion-catalyzed coordination-covalent dual cross-linking mechanism improve the density and stability of the material's micronetwork.

[0083] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A processing technology for mycelial synthetic materials, characterized in that, Includes the following steps: S1. Substrate pretreatment: The wet mycelial substrate is heat-treated at 70-80℃, and the moisture content of the mycelial substrate after treatment is controlled to be 40%-50%. S2, Vacuum Pulse Permeation and Activation: The mycelial matrix treated in S1 is placed in a vacuum environment, and the pore air is discharged under a negative pressure of -0.08 to -0.095 MPa. Then, an alkaline activation precursor emulsion is drawn in until the mycelial matrix is ​​submerged. The pressure is restored to normal or a positive pressure of 0.2 to 0.4 MPa is applied for impregnation. The mycelium is swollen and deacetylated and activated by the strong alkaline environment. The alkaline activated precursor emulsion is made from raw materials comprising the following parts by weight: based on 100 parts deionized water, it comprises 10-20 parts sodium lignosulfonate and 5-10 parts epoxidized soybean oil, and the pH value of the emulsion is adjusted to 11.5-13.0 by adding an alkali adjuster; S3, Acidic Impact Phase Separation and Locking: After the mycelial matrix impregnated with S2 is drained, it is immersed in acidic phase transformation and locking solution for treatment. The acidic environment and the alkalinity inside the mycelial matrix induce the in-situ precipitation of sodium lignin sulfonate and complete the coordination and locking of metal ions. The acidic phase inversion locking solution is an aqueous solution containing a metal salt, with a metal salt concentration of 0.5–1.5 mol / L, and the pH value of the solution is adjusted to 1.0–2.5 by adding an acid adjuster. S4. Drying and curing: The mycelial matrix treated in S3 is washed with water until neutral, pre-dried to a moisture content of 15% to 20%, and then placed in a mold for two-stage hot pressing curing: the first stage temperature is 95 to 105℃ and the pressure is 2.0 to 4.0 MPa; the second stage temperature is 140 to 160℃ and the pressure is 8.0 to 12.0 MPa.

2. The processing technology for mycelial synthetic materials according to claim 1, characterized in that, The preparation method of the alkaline activated precursor emulsion described in S2 is as follows: Sodium lignosulfonate is dissolved in deionized water, sodium hydroxide aqueous solution is added dropwise to adjust the pH value to 11.5-13.0, then epoxidized soybean oil is added, and the mixture is sheared and homogenized at a speed of 5,000-8,000 rpm for 5-10 minutes using a high shear dispersion emulsifier to obtain an oil-in-water O / W type emulsion.

3. The mycelium synthesis material processing technology according to claim 1, characterized in that, The metal salt in the acidic phase inversion locking solution described in S3 is selected from either aluminum chloride hexahydrate AlCl3·6H2O or anhydrous ferric chloride FeCl3; the acid regulator is hydrochloric acid.

4. The processing technology for mycelial synthetic materials according to claim 1, characterized in that, The method for preparing the wet mycelial matrix described in S1 is as follows: Ganoderma lucidum is used as the strain to produce mycelium, and lignocellulose waste with a particle size of 1.0 to 3.0 mm is used as the culture medium substrate. The mycelium is cultured at 25°C in the dark until it completely covers the culture medium substrate, and finally a wet mycelial matrix is ​​obtained with an initial water content of 50% to 70%.

5. The processing technology for mycelial synthetic materials according to claim 1, characterized in that, In S2, the total immersion time for vacuum pulse penetration and activation is 30 to 60 minutes; in S3, the treatment method for acidic impact phase separation and locking is immersion or spraying, and the treatment time is 15 to 30 minutes.

6. The processing technology for mycelial synthetic materials according to claim 1, characterized in that, In S4, the first stage of hot pressing takes 5 to 10 minutes, the second stage of hot pressing takes 10 to 20 minutes, and after hot pressing, the material is held under pressure and cooled to below 60°C before demolding.

7. The processing technology for mycelial synthetic materials according to claim 1, characterized in that, The sodium lignosulfonate has a weight-average molecular weight of 8,000–15,000 Da and a sulfonation degree of 1.5–2.5 mmol / g; the epoxidized soybean oil has an epoxy value ≥6.0% and a viscosity of 300–500 cP.

8. A mycelium synthetic material, prepared using the mycelium synthetic material processing technology according to any one of claims 1 to 7, characterized in that, The material is made from raw materials containing the following components through chemical modification and hot-press curing: Mycelial matrix; Modified component, said modified component being derived from the reaction product of the above-mentioned alkaline activated precursor emulsion and acidic phase inversion locking solution; The modified components include sodium lignosulfonate crosslinker, ring-opening cured epoxidized soybean oil, and metal ion ligands. Furthermore, during the preparation process, based on 100 parts by weight of deionized water, the amount of sodium lignosulfonate is 10-20 parts, and the amount of epoxidized soybean oil is 5-10 parts.

9. The mycelium synthetic material according to claim 8, characterized in that, The material has an interpenetrating polymer network structure, in which the amino groups on the surface of the mycelium fibers, the sulfonic acid groups of sodium lignin sulfonate, and metal ions form coordination crosslinks, and the epoxidized soybean oil forms covalent crosslinks with the active groups of the mycelium and lignin; the gel content of the material is greater than 90%.

10. A mycelium synthetic material according to claim 8, characterized in that, The material has a density of 1.25–1.40 g / cm³, a thickness expansion rate of less than 5% after 24 hours of water absorption, and a static bending strength greater than 40 MPa.

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