Mushroom leather and preparation method thereof

Abstract

The invention discloses mushroom element leather and a preparation method thereof, and belongs to the technical field of green and environment-friendly materials. The method for preparing the mushroom leather comprises the following steps: (1) performing deacetylation on mushrooms in an alkaline solution, and then neutralizing and washing to obtain deacetylated mushrooms; (2) carrying out brooming treatment on the deacetylated mushrooms, and filtering to obtain broomed mushrooms; (3) adding a cross-linking agent and a plasticizer into the mushroom subjected to brooming treatment to carry out a cross-linking plastification reaction, and after the reaction is finished, filtering to obtain the mushroom subjected to cross-linking plastification; and (4) carrying out mold pressing or hot press molding on the mushrooms subjected to cross-linking plastification, so as to obtain the mushroom element leather. The mushroom element leather prepared by the invention can realize full biological degradation, and has certain mechanical properties.

Description

Technical Field

[0001] The invention relates to mushroom leather and a preparation method thereof, belonging to the technical field of green environmentally friendly materials. Background Art

[0002] Fruiting bodies are a renewable natural resource, and their growth is part of the fungal life cycle. Fruiting bodies are spore-producing structures of higher fungi, consisting of organized mycelium. The morphology of fruiting bodies of large fungi in nature is quite complex, and the shapes vary from fungus to fungus, including umbrella-shaped, pen-shaped, head-shaped, ear-shaped, tongue-shaped, spherical, flower-shaped, and tree-shaped. Higher fungi can be mainly divided into the following five categories: agaric, non-gill fungi, colloid fungi, gastric fungi, and ascomycetes. Fruiting bodies can be eaten fresh or processed. Fungal fruiting bodies can be produced by fermentation processes and culture medium preparation, inoculation, and incubation. The culture medium may be in the form of a substrate that can be obtained from cheap sources such as agricultural biomass and industrial waste, but it can also be converted into high-value-added food and medicine. Therefore, the use of fungi is important for both the economy and the environment.

[0003] Nowadays, most substitutes for animal materials such as artificial fur, artificial leather and artificial wool on the market are made of plastic surface made of polyurethane (PU) or polyvinyl chloride (PVC) and nylon, acrylic or polyester fabrics. In essence, they are still synthetic fiber products and a type of plastic. Moreover, the raw materials are all taken from petrochemical resources, and microplastics frequently fall off. In addition, these materials are difficult to degrade and will cause secondary damage to the environment when incinerated as garbage.

[0004] As consumers become more environmentally conscious, they are gradually becoming resistant to this kind of artificial leather that is not environmentally friendly. This has made artificial leather based on plant fibers, such as apple, pineapple, cactus, and mycelium leather, which contains a small amount of plastic, become popular. Among them, "mycelium leather" is considered to be one of the most promising vegan leather materials. It can form vegan leather with the morphology of animal leather through the growth of fungal mycelium without any animal ingredients.

[0005] Although mycelium leather has superior properties to other vegan leathers, mycelium growth is affected by environmental, chemical, material, and thigmotropism. More importantly, current methods for growing mycelium leather materials require multiple containers and multiple transfer steps, which means that the mycelium is easily contaminated by other microorganisms that can disrupt the fermentation process.

[0006] Therefore, in order to quickly industrialize the production of vegan leather, it is urgent to find a suitable method to prepare vegan leather. Summary of the invention

[0007] [Technical issues]

[0008] Most alternatives to animal materials such as faux fur, leather and wool are not environmentally friendly.

[0009] The method for growing mycelium leather material requires multiple containers, multiple steps, and is cumbersome to operate; and it is easy to be contaminated by microorganisms, which can destroy the fermentation process.

[0010] [Technical solution]

[0011] In order to solve the above problems, the present invention uses a method of depolymerization and reorganization of mushroom fruiting bodies to mass produce mushroom leather. The mushroom leather prepared by the present invention can achieve full biodegradability and has certain mechanical properties.

[0012] The first object of the present invention is to provide a method for preparing mushroom leather, comprising the steps of:

[0013] (1) deacetylating the mushrooms in an alkaline solution, then neutralizing and washing with water to obtain deacetylated mushrooms;

[0014] (2) subjecting the deacetylated mushrooms to a brooming treatment, filtering, and obtaining brooming-treated mushrooms;

[0015] (3) adding a crosslinking agent and a plasticizer to the mushrooms after the brooming treatment to carry out a crosslinking and plasticizing reaction, and filtering after the reaction to obtain the crosslinked and plasticized mushrooms;

[0016] (4) The mushrooms after cross-linking and plasticization are molded or hot-pressed to obtain mushroom leather.

[0017] In one embodiment of the present invention, the mushrooms in step (1) are one or more of well-grown oyster mushrooms, shiitake mushrooms, straw mushrooms, button mushrooms, enoki mushrooms, hericium erinaceus, white jade mushrooms, king oyster mushrooms, Agaricus bisporus, black fungus, white fungus, chanterelles, morels, northern wind mushrooms, bamboo fungus, etc.

[0018] In one embodiment of the present invention, the alkaline solution in step (1) is a sodium hydroxide solution, the mass concentration of the sodium hydroxide solution is 10-45%, and the solvent is water.

[0019] In one embodiment of the present invention, the ratio of the alkaline solution to the mushroom in step (1) is 0.5-1.5 mL: 1 g, more preferably 1 mL: 1 g.

[0020] In one embodiment of the present invention, the deacetylation in step (1) is carried out at 95-105° C. for 50-70 min, more preferably at 100° C. for 60 min.

[0021] In one embodiment of the present invention, the neutralization in step (1) is carried out using a hydrochloric acid solution, the concentration of the hydrochloric acid solution is 10-50%, and the solvent is water.

[0022] In one embodiment of the present invention, the brooming treatment in step (2) is carried out in a wall breaking machine, and the specific parameter settings are: the rotation speed is 10000-30000rpm, and the processing time is 0.5-1.5min.

[0023] In one embodiment of the present invention, the filtration in step (2) is performed using medium-speed filter paper.

[0024] In one embodiment of the present invention, in step (3), the cross-linking agent includes one or more of genipin, tyrosinase, glutaraldehyde, sodium trimetaphosphate and sodium tripolyphosphate; the plasticizer includes one or more of urea, a deep eutectic solvent (DES), polyethylene glycol (PEG), sorbitol, glycerol and ethanolamine; wherein the deep eutectic solvent (DES) includes a low eutectic solvent having a molar ratio of choline chloride to urea of ​​1:2; and the molecular weight of the polyethylene glycol (PEG) is above 1000.

[0025] In one embodiment of the present invention, in step (3), the mass ratio of the cross-linking agent to the mushrooms after brooming is 0-10%, more preferably 2-6%, and further preferably 4%; the mass ratio of the plasticizer to the mushrooms after brooming is 0-20%, more preferably 4-14%, and further preferably 8%.

[0026] In one embodiment of the present invention, the cross-linking plasticization reaction in step (3) is carried out at 80-95°C for 40-60 minutes, more preferably at 90°C for 45 minutes.

[0027] In one embodiment of the present invention, the filtration in step (3) is performed using medium-speed filter paper.

[0028] In one embodiment of the present invention, the hot pressing in step (4) is performed at a temperature of 90-110° C. for 1-3 min; and the molding is performed at a pressure of 0.5-1.5 MPa for 1-3 min.

[0029] The second object of the present invention is the mushroom leather prepared by the method according to the present invention.

[0030] The third object of the present invention is to provide a method for preparing artificial leather, wherein the method comprises adding PU before forming the mushroom leather, specifically mixing the mushroom after cross-linking and plasticization with polyurethane (PU) and performing hot pressing or molding to obtain artificial leather.

[0031] In one embodiment of the present invention, the mass ratio of the mushroom to polyurethane (PU) after cross-linking and plasticization is 1:0.5-2.

[0032] The fourth object of the present invention is the artificial leather prepared by the method of the present invention.

[0033] The fifth purpose of the present invention is the application of the mushroom leather and artificial leather described in the present invention in the textile field.

[0034] In one embodiment of the present invention, the application is to prepare a bag by compounding mushroom leather and lining cloth.

[0035] In one embodiment of the present invention, the application is to use the artificial leather for preparing functional fabrics.

[0036] [Beneficial Effects]

[0037] (1) The mechanical properties of the mushroom leather prepared by the present invention are greatly improved, and its breaking strength can reach above 11.1 MPa, and its breaking elongation is above 31.7%.

[0038] (2) The mushroom leather prepared by the present invention can be fully biodegraded and is a green and environmentally friendly material.

[0039] (3) The present invention adopts deacetylation and fibrillation to make the fiber cell wall produce fluff and fibrillation. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 The effects of different concentrations of sodium hydroxide solution in Example 2 on the mechanical properties of Flammulina velutipes leather.

[0041] Figure 2 The effect of different brooming times on the mechanical properties of Flammulina velutipes leather in Example 3.

[0042] Figure 3 The effect of different amounts of plasticizer PEG in Example 4 on the mechanical properties of Flammulina velutipes leather.

[0043] Figure 4 The effect of different amounts of cross-linking agent glutaraldehyde on the mechanical properties of Flammulina velutipes leather in Example 5. DETAILED DESCRIPTION

[0044] The preferred embodiments of the present invention are described below. It should be understood that the embodiments are for better explaining the present invention and are not used to limit the present invention.

[0045] Test method:

[0046] Mechanical property test: The samples were cut into 5×100 mm long strips and subjected to tensile test on a universal material testing machine at a tensile speed of 40 mm / min.

[0047] In the examples, where the meaning of "%" is not specifically specified, it refers to mass percentage, and where the solvent is not specifically specified, water is used as the solvent.

[0048] Example 1

[0049] A method for preparing Flammulina velutipes leather comprises the following steps:

[0050] (1) placing the Flammulina velutipes in a 20% sodium hydroxide aqueous solution at a ratio of 1 g to 1 mL, deacetylation treatment at 100° C. for 60 min, neutralizing with a 25% hydrochloric acid solution, and washing with water to obtain deacetylated Flammulina velutipes;

[0051] (2) placing the deacetylated Flammulina velutipes in a wall breaking machine, brooming the mixture at a speed of 20,000 rpm for 1 min, and filtering the mixture with medium-speed filter paper to obtain broomed Flammulina velutipes;

[0052] (3) adding 4% of a cross-linking agent glutaraldehyde and 8% of a plasticizer PEG1200 to the Flammulina velutipes after the brooming treatment, and performing a cross-linking and plasticizing reaction at 90° C. for 30 minutes. After the reaction is completed, filtering is performed using a medium-speed filter paper to obtain the Flammulina velutipes after cross-linking and plasticization;

[0053] (4) The cross-linked and plasticized Flammulina velutipes was hot-pressed at 100° C. for 2 min to obtain Flammulina velutipes leather.

[0054] Example 2

[0055] The mass concentration of the sodium hydroxide aqueous solution in step (1) of Example 1 was adjusted to 10, 30, 40, and 50%, and the other concentrations were kept consistent with Example 1 to obtain Flammulina velutipes leather.

[0056] The obtained Flammulina velutipes leather was subjected to performance tests, and the test results were as follows: Figure 1 ;

[0057] from Figure 1 It can be seen that when the concentration of sodium hydroxide solution is 20%, the tensile strength and elongation at break of Flammulina leather are the best, and the toughness of the raw mycelium fiber is well retained; when the concentration is lower than 20%, the mechanical properties of Flammulina leather are poor, because the low concentration of NaOH leads to a low degree of deacetylation, which affects the subsequent cross-linking effect, so the tensile strength is poor; when the concentration is higher than 20%, the raw fiber and toughness loss are too large, which is not conducive to the preparation of Flammulina leather. Therefore, the optimal concentration of sodium hydroxide solution is 20%.

[0058] Example 3

[0059] The brooming time 1 min in step (2) of Example 1 was adjusted to 0.5, 1.5, 2, 2.5, and 3 min, and the rest was kept consistent with Example 1 to obtain enoki mushroom leather.

[0060] The obtained Flammulina velutipes leather was subjected to performance tests, and the test results were as follows: Figure 2 ;

[0061] from Figure 2 It can be seen that when the brooming time is 0.5-1.5min, the tensile strength of the Flammulina velutipes leather reaches more than 15MPa, and the elongation at break reaches more than 50%; when the brooming time is 1min, the mechanical properties of the Flammulina velutipes leather are the best, because when the brooming time is 1min, the Flammulina velutipes fruiting body is partially dissociated, but not completely dissociated into single fibers. In the subsequent treatment, the mycelium fibers are entangled with each other, so the mechanical properties are better; while insufficient brooming time will cause the Flammulina velutipes mycelium to be too large, which is not conducive to subsequent treatment; when the brooming time is too long, the Flammulina velutipes fruiting body fibers are too broken, which makes subsequent filtration difficult, and there is no entanglement between the fibers, and the mechanical properties are poor. Therefore, the best brooming time is 1min.

[0062] Example 4

[0063] The amount of plasticizer PEG1200 in step (3) of Example 1 was adjusted to 0, 2, 4, 6, 8 (Example 1), 10, 12, 14, 16, 18, 20%, and the rest was kept consistent with Example 1 to obtain enoki mushroom leather.

[0064] The obtained Flammulina velutipes leather was subjected to performance tests. The test results Figure 3 :

[0065] from Figure 3 It can be seen that as the plasticizer content increases from 0 to 8%, its tensile strength and elongation at break increase accordingly. When the plasticizer content continues to increase, its tensile strength decreases slightly, and the elongation at break decreases significantly. This may be because there is a hydrogen bond force between the hydrophilic plasticizer and chitin and dextran, which reduces the molecular force between chitin and dextran and destroys their rigid structure, thus reducing the tensile strength. At the same time, due to the reduction of intermolecular forces, the ability of the film's molecular chains to move and deform is enhanced, so the toughness is enhanced and the elongation at break is also enhanced. Therefore, the optimal amount of plasticizer is 8%.

[0066] Example 5

[0067] The amount of the cross-linking agent glutaraldehyde in step (3) of Example 1 was adjusted to 0, 2, 4 (Example 1), 6, 8, and 10%, and the rest was kept consistent with Example 1 to obtain Flammulina velutipes leather.

[0068] The obtained Flammulina velutipes leather was subjected to performance tests. The test results Figure 4 :

[0069] from Figure 4 It can be seen that as the cross-linking agent content increases from 0 to 4%, its tensile strength and elongation at break increase accordingly. When the cross-linking agent content continues to increase, its tensile strength decreases slightly, and the elongation at break decreases significantly. This may be because the chitosan and chitin in the mycelium are cross-linked with glutaraldehyde. The more cross-linking agents there are, the more cross-linking groups there are, and the more connection points between the mycelium, the stronger the strength. However, excessive cross-linking makes the membrane material feel harder, the flexibility worsens, and the elongation at break also decreases. Therefore, the optimal amount of cross-linking agent is 4%.

[0070] Example 6

[0071] The enoki mushrooms in step (1) of Example 1 were adjusted to oyster mushrooms, shiitake mushrooms and hericium erinaceus, and the rest were kept consistent with Example 1 to obtain plain leather.

[0072] The obtained plain leather was subjected to performance tests, and the test results are shown in Table 1:

[0073] Table 1

[0074] mushroom Tensile strength(MPa) Elongation at break (%) Flammulina velutipes (Example 1) 20.9 71.3 Oyster Mushroom 11.1 43.3 mushroom 12.3 31.7 Hericium erinaceus 12.8 51.1

[0075] It can be seen from Table 1 that different types of mushrooms have different mechanical properties. This is because different types of mushrooms have different fiber lengths, and mushrooms with longer fibers have better mechanical properties.

[0076] Comparative Example 1

[0077] The brooming speed in step (2) of Example 1 was omitted to be 40000 rpm, and the rest was kept the same as Example 1 to obtain Flammulina velutipes leather.

[0078] Comparative Example 2

[0079] The cross-linking agent and plasticizer in step (3) of Example 1 were omitted, and the other steps were kept the same as in Example 1 to obtain enoki mushroom leather.

[0080] Comparative Example 3

[0081] The cross-linking agent in step (3) of Example 1 was adjusted to sodium tripolyphosphate, and the other steps were kept consistent with Example 1 to obtain enoki mushroom leather.

[0082] Comparative Example 4

[0083] The plasticizer in step (3) of Example 1 was adjusted to glycerol, and the other steps were kept the same as in Example 1 to obtain Flammulina velutipes leather.

[0084] Comparative Example 5

[0085] The hot pressing in step (4) of Example 1 was adjusted to cold pressing, specifically cold pressing at 25° C. for 1 min. The other steps were kept the same as in Example 1 to obtain enoki mushroom leather.

[0086] The obtained Flammulina velutipes leather was subjected to performance tests, and the test results are shown in Table 2:

[0087] Table 2

[0088] example Tensile strength(MPa) Elongation at break (%) Comparative Example 1 10.3 46.3 Comparative Example 2 9.4 10.3 Comparative Example 3 18.6 22.8 Comparative Example 4 20.6 17.8 Comparative Example 5 17.3 60.4

[0089] From Table 2 we can see that:

[0090] In Comparative Example 1, the brooming speed was adjusted, so that the length of the Flammulina velutipes mycelium fibers changed, thereby affecting the performance of the Flammulina velutipes leather;

[0091] In Comparative Example 2, since the cross-linking agent and plasticizer were omitted, the cross-linking degree and plasticity of the Flammulina velutipes leather were reduced, affecting its mechanical properties;

[0092] Comparative Examples 3 and 4 adjusted the types of cross-linking agent and plasticizer, which affected the cross-linking degree and plasticity of the Flammulina velutipes leather, and thus affected the mechanical properties;

[0093] In Comparative Example 5, hot pressing was changed to cold pressing. Compared with Example 1, the tensile strength and elongation at break decreased to a certain extent, indicating that hot pressing has a reinforcing effect.

[0094] Example 7

[0095] The plasticizer PEG1200 in step (3) of Example 1 was adjusted to DES (molar ratio, choline chloride:urea=1:2) with a concentration of 8%, and the rest was kept consistent with Example 1 to obtain enoki mushroom leather.

[0096] The obtained Flammulina velutipes leather was subjected to performance tests, and the test results were as follows:

[0097] The tensile strength is 16.4MPa and the elongation at break is 87.5%. Compared with the same concentration of PEG as a plasticizer in Table 1, the plasticizing effect of DES is better than that of PEG. This is because the choline chloride and urea components in DES as plasticizers reduce the interaction between endogenous macromolecules (chitin and glucan) in Flammulina velutipes, resulting in a decrease in tensile strength. At the same time, due to the reduction of intermolecular forces, the molecular chains of the membrane are more likely to slip, resulting in an increase in the elongation at break.

[0098] Example 8 Compounded with PU

[0099] A method for preparing artificial leather comprises the following steps:

[0100] (1) placing the Flammulina velutipes in a 20% sodium hydroxide aqueous solution at a ratio of 1 g to 1 mL, deacetylation treatment at 100° C. for 60 min, neutralizing with a 25% hydrochloric acid solution, and washing with water to obtain deacetylated Flammulina velutipes;

[0101] (2) placing the deacetylated Flammulina velutipes in a wall breaking machine, brooming the mixture at a speed of 20,000 rpm for 1 min, and filtering the mixture with medium-speed filter paper to obtain broomed Flammulina velutipes;

[0102] (3) adding 4% of a cross-linking agent glutaraldehyde and 8% of a plasticizer PEG1200 to the Flammulina velutipes after the brooming treatment, and performing a cross-linking and plasticizing reaction at 90° C. for 30 minutes. After the reaction is completed, filtering is performed using a medium-speed filter paper to obtain the Flammulina velutipes after cross-linking and plasticization;

[0103] (4) The cross-linked and plasticized Flammulina velutipes and polyurethane PU (waterborne polyurethane, solid content 35%) were hot-pressed at 100° C. for 2 min in a mass ratio of 1:1 to obtain artificial leather.

[0104] The obtained artificial leather was subjected to performance tests, and the test results are shown in Table 3:

[0105] It can be seen from Table 3 that the tensile strength and elongation at break are greatly improved after the enoki mushroom leather is compounded with PU.

[0106] Table 3

[0107] example Tensile strength(MPa) Elongation at break (%) Example 1 20.9 71.3 Example 5 40.2 146.3

[0108] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A method for preparing mushroom leather, characterized in that: The steps include: (1) deacetylating the mushrooms in an alkaline solution, then neutralizing and washing with water to obtain deacetylated mushrooms; (2) subjecting the deacetylated mushrooms to a brooming treatment, filtering, and obtaining brooming-treated mushrooms; (3) adding a crosslinking agent and a plasticizer to the mushrooms after the brooming treatment to carry out a crosslinking and plasticizing reaction, and filtering after the reaction to obtain the crosslinked and plasticized mushrooms; (4) The mushrooms after cross-linking and plasticization are molded or hot-pressed to obtain mushroom leather.

2. The method according to claim 1, characterized in that The mushrooms described in step (1) are one or more of well-grown oyster mushrooms, shiitake mushrooms, straw mushrooms, button mushrooms, enoki mushrooms, hericium erinaceus, white jade mushrooms, king oyster mushrooms, Agaricus bisporus, black fungus, white fungus, chanterelles, morels, northern mushrooms, bamboo fungus, etc.

3. The method according to claim 1, characterized in that In step (1), the alkaline solution is a sodium hydroxide solution, and the mass concentration of the sodium hydroxide solution is 10-50%.

4. The method according to claim 1, characterized in that The brooming treatment in step (2) is carried out in a wall breaking machine, and the specific parameter settings are: the rotation speed is 10000-30000rpm, and the processing time is 0.5-1.5min.

5. The method according to claim 1, characterized in that In step (3), the cross-linking agent includes one or more of genipin, tyrosinase, glutaraldehyde, sodium trimetaphosphate and sodium tripolyphosphate; the plasticizer includes one or more of urea, low eutectic solvent, polyethylene glycol, sorbitol, glycerol and ethanolamine; the mass ratio of the cross-linking agent to the mushroom after brooming is 0-10%; the mass ratio of the plasticizer to the mushroom after brooming is 0-20%.

6. Mushroom leather prepared by the method according to any one of claims 1 to 5.

7. A method for preparing artificial leather, characterized in that: The method described is to add PU before forming the method for preparing mushroom leather in claim 1.

8. The method according to claim 7, characterized in that The method specifically comprises mixing the mushrooms after cross-linking and plasticization with polyurethane and performing hot pressing or molding to obtain artificial leather; wherein the mass ratio of the mushrooms after cross-linking and plasticization to the polyurethane is 1:0.5-2.

9. The artificial leather prepared by the method described in claim 7 or 8.

10. Use of the mushroom leather according to claim 7 and the artificial leather according to claim 9 in the textile field.

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