Wheat straw fiber-based full-degradable molded product slurry as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of disposable tableware, and particularly relates to wheat straw fiber-based full-degradable molded product slurry as well as a preparation method and application thereof. The wheat straw fiber-based fully-degradable molded product slurry is prepared from wheat straw slurry, wheat bran, modified soybean protein glue, palm wax, nano cellulose, chitosan, triethyl citrate, sodium carboxymethyl cellulose and calcium sulfate. Wherein the wheat straw slurry adopts a microbial pretreatment process, the usage amount of chemicals is reduced, pulping waste liquid can be recycled as an organic fertilizer, and the problem of high pollution caused by traditional chemical treatment is avoided; all auxiliary agents in the formula, such as modified soybean protein glue, palm wax, chitosan and the like, are biodegradable materials, and the final product can be completely degraded in the natural environment and meets the full-degradation standard.

Description

Technical Field

[0001] The invention belongs to the technical field of disposable tableware, and in particular relates to a straw fiber-based fully degradable molded product slurry, a manufacturing method and an application thereof. Background Art

[0002] With the rapid development of the economy, people's demand for convenience foods is increasing. The development of the fast food industry has led to a rapid increase in the demand for disposable tableware. Plant fiber tableware has attracted much attention due to its excellent mechanical properties, biodegradability and low environmental pollution.

[0003] Straw is one of the largest biomass resources in my country, with an annual output of about 800 million tons. Improper handling of straw puts tremendous pressure on the environment. High-value utilization of this huge resource can not only alleviate energy and environmental problems, but also generate huge economic benefits.

[0004] While the manufacturing technology for straw-based tableware has made some progress, it still faces challenges such as insufficient mechanical properties, poor water resistance, and reliance on non-degradable additives. Chen Fukuai's "A Method for Manufacturing Disposable Tableware Based on Crop Straw" (CN113652096A) uses straw as a base material, but focuses solely on improving the tableware's appearance and color. It fails to address the poor mechanical properties caused by the rigid structure of straw fibers, resulting in no significant improvement in tableware quality.

[0005] Yang Guogang's "A Disposable Oil-Proof, Water-Resistant, and Degradable Lunch Box and Its Preparation Method" (CN104845400A) uses hydroxypropyl methylcellulose or polyvinyl alcohol (PVA) as an adhesive and paraffin as a waterproofing agent. However, PVA can produce microplastic pollution during degradation, and while paraffin is waterproof, it has poor biodegradability and does not meet the requirement for full degradation. Furthermore, the straw fiber is not pretreated, leaving its rigid structure intact, resulting in insufficient mechanical properties in the finished product. Summary of the Invention

[0006] In response to the shortcomings of the existing technology, the present invention provides a straw fiber-based fully degradable molded product slurry, a manufacturing method and application thereof. The straw fiber of the present invention is pretreated with a composite microbial agent instead of traditional chemical treatment to reduce environmental pollution; fully degradable adjuvants such as modified soy protein glue and palm wax are used to solve the problems of insufficient water resistance and non-degradability in the existing technology; at the same time, the comprehensive performance of tableware is improved by optimizing the formula to meet the dual needs of environmental protection and practicality.

[0007] The technical solutions of the present invention are as follows: The wheat straw fiber-based fully degradable molding product slurry comprises the following components in parts by weight: 60-70 parts of wheat straw slurry, 8-10 parts of wheat bran, 8-12 parts of modified soy protein gum, 2-4 parts of palm wax, 3-5 parts of nanocellulose, 2-3 parts of chitosan, 1-2 parts of triethyl citrate, 2-4 parts of sodium carboxymethyl cellulose, and 8-10 parts of calcium sulfate.

[0008] According to the preferred embodiment of the present invention, the straw slurry is prepared according to the following method: Preparation: sorting the wheat straw raw materials, removing mildew and debris, and squeezing the raw materials; washing the wheat straw and drying it; soaking the dried wheat straw in water until it covers the straw; adding 1.1-1.5% sodium bicarbonate by weight of the water; mixing evenly; soaking and swelling for 24-48 hours; taking out the wheat straw to obtain the swollen wheat straw; adding 0.01-0.3% of the dry weight of the wheat straw to the swollen wheat straw; the composite microbial pretreatment agent The agent is prepared by compounding Bacillus subtilis solution, Bacillus cereus solution, Bacillus licheniformis solution, Bacillus pumilus solution and Bacillus amyloliquefaciens solution in a mass ratio of (1-3):(1-2):(1-3):(1-3):(1-3); adding water to cover the wheat straw, mixing evenly, fermenting and degrading at 35-40°C for 24-48 hours, taking out the wheat straw and drying it to obtain pretreated wheat straw, and grinding the pretreated wheat straw to prepare wheat straw slurry.

[0009] More preferably, the viable cell count of the Bacillus subtilis liquid is 1.0×10 9 cfu / mL~1.0×10 11 cfu / mL, and the number of viable bacteria of Bacillus cereus liquid was 2.0×10 9 cfu / mL~5.0×10 10 cfu / mL, and the number of viable bacteria in the Bacillus licheniformis solution was 1.0×10 10 cfu / mL~5.0×10 11 cfu / mL, and the number of viable bacteria of Bacillus pumilus was 2.0×10 9 cfu / mL~ 1.0×10 11 cfu / mL, the number of viable bacteria of Bacillus amyloliquefaciens culture liquid was 1.0×10 9 cfu / mL~5.0×10 10 cfu / mL.

[0010] Further preferably, the Bacillus subtilis is Bacillus subtilis CICC 10028, the Bacillus cereus is Bacillus cereus CICC 10184, the Bacillus licheniformis is Bacillus licheniformis CICC 10084, the Bacillus pumilus is Bacillus pumilus CICC 22395, and the Bacillus amyloliquefaciens is Bacillus amyloliquefaciens CICC10160, all of which are purchased from the China Industrial Microorganism Collection Center.

[0011] Further preferably, the refining is a two-stage refining, and the refining parameters are: coarse grinding, disc grinding gap 0.5-1.5 mm, rotation speed 1200-1500 r / min, fiber length 1.5-2.0 mm; fine grinding, disc grinding gap 0.15-0.25 mm, rotation speed 2500-3000 r / min, fiber length 0.8-1.2 mm.

[0012] Further preferably, the moisture content of the wheat straw slurry obtained after refining is controlled to be 8-12%.

[0013] The method for producing the above-mentioned wheat straw fiber-based fully degradable molded product slurry comprises the following steps: The wheat straw slurry is evenly mixed with wheat bran, modified soybean protein glue, palm wax, nanocellulose, chitosan, triethyl citrate, sodium carboxymethyl cellulose and calcium sulfate to obtain wheat straw fiber-based fully degradable molding product slurry.

[0014] Preferably, according to the present invention, the ingredients are mixed in steps. The first step is to add nanocellulose to the straw slurry and stir and disperse it at high speed. The second step is to add molten palm wax at 60-80°C and mix it at medium speed. The third step is to add modified soy protein gum and other additives and stir and prevent foaming at low speed.

[0015] Further preferably, the high-speed stirring and dispersing condition is 1500 r / min stirring for 10 min; the medium-speed mixing condition is 800 r / min stirring for 5-10 min; and the low-speed stirring condition is 300 r / min stirring for 3-8 min.

[0016] Application of the above-mentioned wheat straw fiber-based fully degradable molding product slurry in the preparation of molding products.

[0017] According to a preferred embodiment of the present invention, the molded product includes tableware, egg trays, and cup trays.

[0018] Preferably, according to the present invention, the molded product is obtained by compression molding wheat straw fiber-based fully degradable molded product slurry.

[0019] According to a preferred embodiment of the present invention, the compression molding method is: using a quantitative feeder to transport the straw fiber-based fully degradable molded product slurry to the mold, setting the mold temperature and pressure, and using three-stage hot pressing to press the mixed material; after the pressing is completed, wait for the mold temperature to drop below 60°C, take out the tableware, and obtain the molded product by trimming.

[0020] Further preferably, the specific operation of the three-stage hot pressing is as follows: the first stage is a preheating stage, the mold temperature is raised to 90-110°C, the pressure is set to 2-5 MPa, the processing time is 1-3 minutes, and the water vapor is discharged after the end; The second stage is the main pressing stage, where the mold temperature is raised to 150-160°C, the pressure is set to 6-9 MPa, and the processing time is 8-12 minutes; The third stage is the pressure holding stage. The specific operation is: the mold temperature is raised to 170-190℃, the pressure is set to 10-12 MPa, and the processing time is 5-7 minutes.

[0021] Beneficial effects: 1. Significantly improved environmental performance: The microbial pretreatment process is used to reduce the use of chemical drugs. The pulping waste liquid can be recycled as organic fertilizer, avoiding the high pollution problem of traditional chemical treatment. All auxiliary agents in the formula (such as modified soy protein glue, palm wax, chitosan, etc.) are biodegradable materials. The final product can be completely degraded in the natural environment and meets the full degradation standard.

[0022] 2. Enhanced mechanical properties: Microbial pretreatment destroys the rigid structure of wheat straw fibers, allowing the cellulose to be fully exposed and swelled. Combined with the synergistic effect of sodium carboxymethyl cellulose (CMC) and modified soy protein glue, it significantly improves the bonding force between fibers and enhances the flexural strength of tableware.

[0023] 3. Excellent waterproof and oil-proof performance: Palm wax and nanocellulose (CNF) form a dense nano-network structure, filling the fiber gaps and blocking water penetration, significantly improving the waterproof and oil-proof performance of tableware.

[0024] 4. Outstanding antibacterial properties: Chitosan has broad-spectrum antibacterial properties that can inhibit common microorganisms such as Escherichia coli and Staphylococcus aureus, and can effectively inhibit the growth of bacteria in food residues.

[0025] 5. Resource recycling: The main raw material of the present invention is wheat straw fiber, which makes rational use of existing resources, improves the conversion and utilization value of wheat straw, reduces the production cost of disposable tableware, reduces pollution problems caused by improper straw processing, and realizes high-value utilization of wheat straw. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the production process flow of wheat straw fiber-based fully biodegradable molded tableware.

[0027] Figure 2 This is a picture of the wheat straw fiber-based fully biodegradable molded tableware produced in Example 1. DETAILED DESCRIPTION

[0028] The present invention will be further described below by way of specific examples, but the scope of protection is not limited thereto. The drugs and reagents used in the examples are commercially available products unless otherwise specified, and any matters not described in detail in the examples are based on the prior art in the art.

[0029] Specific sources of main raw materials: Bacillus subtilis ( Bacillus subtilis ): purchased from China Industrial Microorganism Collection Center, strain number: CICC 10028; Bacillus cereus ( Bacillus cereus ): purchased from China Industrial Microorganism Collection Center, strain number: CICC 10184; Bacillus licheniformis ( Bacillus licheniformis ): purchased from China Industrial Microorganism Collection Center, strain number: CICC 10084; Bacillus pumilus ( Bacillus pumilus ): purchased from China Industrial Microorganism Collection Center, strain number: CICC 22395; Bacillus amyloliquefaciens ( Bacillus amyloliquefaciens ): purchased from China Industrial Microorganism Collection Center, strain number: CICC 10160; Wheat straw (wheat straw) was purchased from Jinan, Shandong; Modified soy protein gel: Product number: KDZ-80, purchased from Henan Kangzhiwang Biotechnology Co., Ltd. Corn starch glue: Product No. 006, purchased from Henan Suda Starch Adhesive Co., Ltd. Polyvinyl alcohol: Product number: YP-217, purchased from Ningxia Yixing New Material Technology Co., Ltd. Palm wax: purchased from Shanghai Zhupin Chemical Co., Ltd. Nanocellulose: Product number: DQNFC-5, purchased from Zibo Daoqin New Materials Co., Ltd. Chitosan: Product number: GTC-CS60, purchased from Shandong Guante Bioengineering Co., Ltd. Triethyl citrate: purchased from Jinan Rongguang Chemical Co., Ltd. Sodium carboxymethyl cellulose: Product number: FUH9-1, purchased from Shandong Pingju Biotechnology Co., Ltd. Sodium bicarbonate solid powder: purchased from Jinan Xintengda Chemical Co., Ltd. Calcium sulfate powder: purchased from Laiwu Taihe Biochemical Co., Ltd.

[0030] The schematic diagram of the manufacturing method of wheat straw fiber-based fully degradable molded tableware in the embodiment is as follows Figure 1 shown.

[0031] Example 1 A method for manufacturing wheat straw fiber-based fully biodegradable molded tableware comprises the following steps: (1) The wheat straw raw material is sorted to remove mildew, debris, etc., and the wheat straw is squeezed using a press and then cleaned; the dried wheat straw is transferred to a swelling tank, water is added to soak the straw, and then 1.2% sodium bicarbonate solid powder is added to the weight of the water, mixed evenly, soaked and swollen for 48 hours, and the wheat straw is taken out to obtain the swollen wheat straw; the swollen wheat straw is sent to a degradation tank, and a composite microbial pretreatment agent is added to the degradation tank at 0.1% of the dry weight of the wheat straw, wherein the composite microbial pretreatment agent is a mixed bacterial solution with a mass ratio of Bacillus subtilis liquid: Bacillus cereus liquid: Bacillus licheniformis liquid: Bacillus pumilus liquid: Bacillus amyloliquefaciens liquid = 1:2:1:2:1; water is added to cover the wheat straw, mixed evenly, fermented and degraded at 37°C for 40 hours, and the wheat straw in the degradation tank is filtered and dried using a filter to obtain the pretreated wheat straw. The wheat straw was refined in two stages using a high-consistency disc mill. The coarse grinding settings were: disc gap 1.0 mm, rotation speed 1500 r / min, and fiber length 1.5-2.0 mm; the fine grinding settings were: disc gap 0.2 mm, rotation speed 3000 r / min, and fiber length 0.8-1.2 mm. 8% water of the wheat straw mass was added during the refining process, and finally a wheat straw slurry with a moisture content of 8% was obtained.

[0032] The viable bacterial count of the Bacillus subtilis liquid is 1.0×10 9 cfu / mL, and the number of viable bacteria of Bacillus cereus liquid was 3.0×10 9 cfu / mL, and the number of viable bacteria in the Bacillus licheniformis solution was 5.0×10 10 cfu / mL, and the number of viable bacteria of Bacillus pumilus was 6.0×10 9 cfu / mL, and the number of viable bacteria of Bacillus amyloliquefaciens culture liquid was 4.0×10 9 cfu / mL.

[0033] (2) The tableware formula is as follows: by weight, 60 parts of wheat straw slurry, 10 parts of wheat bran, 12 parts of modified soy protein glue, 2 parts of palm wax, 5 parts of nanocellulose, 2 parts of chitosan, 2 parts of triethyl citrate, 2 parts of sodium carboxymethyl cellulose, and 8 parts of calcium sulfate. The moisture content of the wheat straw slurry is kept at 8%. In the first step, nanocellulose is added and dispersed at high speed (1500r / min) for 10 minutes; in the second step, molten palm wax at 60℃ is added and mixed at medium speed (800r / min) for 5 minutes; in the third step, modified soy protein glue, wheat bran, chitosan, triethyl citrate, sodium carboxymethyl cellulose, and calcium sulfate are added and stirred at low speed (300r / min) for 3 minutes until uniform, thereby obtaining a slurry for wheat straw fiber-based fully biodegradable molded products.

[0034] (3) Use a quantitative feeder to transport the molded product slurry obtained in step (2) to the mold for preheating treatment. The parameters are set as follows: the mold temperature is raised to 100°C, the pressure is 3 MPa, the treatment is 2 minutes, and the water vapor is discharged after the treatment. After the preheating treatment is completed, the main pressure treatment is carried out. The parameters are set as follows: the mold temperature is raised to 160°C, the pressure is 8 MPa, and the treatment is 10 minutes. After the main pressure treatment is completed, the pressure holding treatment is carried out. The parameters are set as follows: the mold temperature is raised to 180°C, the pressure is 10 MPa, and the treatment is 5 minutes. After the pressure holding treatment is completed, wait until the mold temperature drops below 60°C, take out the tableware, and trim the edges to obtain the finished product. The finished tableware obtained is as follows Figure 2 shown.

[0035] Example 2 A method for manufacturing wheat straw fiber-based fully biodegradable molded tableware comprises the following steps: (1) The wheat straw raw material is sorted to remove mildew, debris, etc., and the wheat straw is squeezed using a press and then cleaned; the dried wheat straw is transferred to a swelling tank, water is added to soak the straw, and then 1.3% sodium bicarbonate solid powder is added to the weight of the water, mixed evenly, and soaked and swollen for 36 hours. The wheat straw is taken out to obtain the swollen wheat straw; the swollen wheat straw is sent to a degradation tank, and a composite microbial pretreatment agent is added to the degradation tank at a weight ratio of 0.05% of the dry weight of the wheat straw, wherein the composite microbial pretreatment agent is a mixed bacterial solution of Bacillus subtilis liquid: Bacillus cereus liquid: Bacillus licheniformis liquid: Bacillus pumilus liquid: Bacillus amyloliquefaciens liquid = 2:1:1:2:1; water is added to cover the wheat straw, mixed evenly, and fermented and degraded at 37°C for 48 hours. The wheat straw in the degradation tank is filtered and dried using a filter to obtain the pretreated wheat straw. The wheat straw was refined in two stages using a high-consistency disc mill. The coarse grinding settings were: disc gap 0.7 mm, speed 1200 r / min, fiber length 1.5-2.0 mm; the fine grinding settings were: disc gap 0.22 mm, speed 2500 r / min, fiber length 0.8-1.2 mm. 10% water of the wheat straw mass was added during refining, and finally a wheat straw slurry with a moisture content of 10% was obtained.

[0036] The viable bacterial count of the Bacillus subtilis liquid is 2.0×10 9 cfu / mL, and the number of viable bacteria of Bacillus cereus liquid was 3.5×10 9 cfu / mL, and the number of viable bacteria in the Bacillus licheniformis solution was 2.0×10 10 cfu / mL, and the number of viable bacteria of Bacillus pumilus was 7.0×10 9 cfu / mL, and the number of viable bacteria of Bacillus amyloliquefaciens culture liquid was 1.5×10 9 cfu / mL.

[0037] (2) The tableware formula is as follows: by weight, 65 parts of wheat straw slurry, 9 parts of wheat bran, 10 parts of modified soy protein gum, 3 parts of palm wax, 4 parts of nanocellulose, 2.5 parts of chitosan, 1.5 parts of triethyl citrate, 3 parts of sodium carboxymethyl cellulose, and 9 parts of calcium sulfate. The moisture content of the wheat straw slurry is maintained at 10%, and the order of addition is the same as in Example 1, wherein the melting temperature of the palm wax is 70°C, the stirring time is 8 minutes at medium speed, and the stirring time is 5 minutes at low speed, to obtain a slurry for wheat straw fiber-based fully degradable molded products.

[0038] (3) The molded product slurry obtained in step (2) is transported to the mold by a quantitative feeder for preheating. The parameters are set as follows: the mold temperature is raised to 110°C, the pressure is 5 MPa, the treatment is carried out for 2 minutes, and the water vapor is discharged after the preheating treatment is completed. After the preheating treatment is completed, the main pressure treatment is carried out. The parameters are set as follows: the mold temperature is raised to 155°C, the pressure is 9 MPa, and the treatment is carried out for 9 minutes. After the main pressure treatment is completed, the pressure holding treatment is carried out. The parameters are set as follows: the mold temperature is raised to 175°C, the pressure is 11 MPa, and the treatment is carried out for 6 minutes. After the pressure holding treatment is completed, the mold temperature is lowered to below 60°C, the tableware is removed, and the edges are trimmed to obtain the finished product.

[0039] Example 3 A method for manufacturing wheat straw fiber-based fully biodegradable molded tableware comprises the following steps: (1) The wheat straw raw material is sorted to remove mildew, debris, etc., and the wheat straw is squeezed using a press and then cleaned; the dried wheat straw is transferred to a swelling tank, water is added to soak the straw, and then 1.4% sodium bicarbonate solid powder is added to the weight of the water, mixed evenly, soaked and swollen for 24 hours, and the wheat straw is taken out to obtain the swollen wheat straw; the swollen wheat straw is sent to a degradation tank, and a composite microbial pretreatment agent is added to the degradation tank at a weight ratio of 0.08% of the dry weight of the wheat straw, wherein the composite microbial pretreatment agent is a mixed bacterial solution of Bacillus subtilis liquid: Bacillus cereus liquid: Bacillus licheniformis liquid: Bacillus pumilus liquid: Bacillus amyloliquefaciens liquid = 2:1:1:2:3; water is added to cover the wheat straw, mixed evenly, fermented and degraded at 37°C for 48 hours, and the wheat straw in the degradation tank is filtered and dried using a filter to obtain the pretreated wheat straw. The wheat straw was refined in two stages using a high-consistency disc mill. The coarse grinding settings were: disc gap 1.2 mm, rotation speed 1300 r / min, and fiber length 1.5-2.0 mm; the fine grinding settings were: disc gap 0.22 mm, rotation speed 2900 r / min, and fiber length 0.8-1.2 mm. 12% water of the wheat straw mass was added during refining, and finally a wheat straw slurry with a moisture content of 12% was obtained.

[0040] The viable bacterial count of the Bacillus subtilis liquid was 1.6×10 9 cfu / mL, and the number of viable bacteria of Bacillus cereus was 4.0×1010 cfu / mL, and the number of viable bacteria in the Bacillus licheniformis solution was 3.0×10 11 cfu / mL, and the number of viable bacteria of Bacillus pumilus was 2.0×10 9 cfu / mL, and the number of viable bacteria of Bacillus amyloliquefaciens culture liquid was 2.5×10 10 cfu / mL.

[0041] (2) The tableware formula is, by weight, 70 parts of wheat straw slurry, 8 parts of wheat bran, 8 parts of modified soy protein gum, 4 parts of palm wax, 3 parts of nanocellulose, 3 parts of chitosan, 1 part of triethyl citrate, 4 parts of sodium carboxymethyl cellulose, and 10 parts of calcium sulfate. The moisture content of the wheat straw slurry is maintained at 12%, and the addition order is the same as in Example 1, wherein the melting temperature of the palm wax is 75°C, the stirring time is 10 minutes at a medium speed, and the stirring time is 8 minutes at a low speed, to prepare a slurry for a fully degradable molded product based on mixed wheat straw fiber.

[0042] (3) The molded product slurry obtained in step (2) is transported to the mold by a quantitative feeder for preheating. The parameters are set as follows: the mold temperature is raised to 95°C, the pressure is 2 MPa, and the treatment is carried out for 3 minutes. After the treatment, the water vapor is discharged. After the preheating treatment is completed, the main pressure treatment is carried out. The parameters are set as follows: the mold temperature is raised to 155°C, the pressure is 9 MPa, and the treatment is carried out for 9 minutes. After the main pressure treatment is completed, the pressure holding treatment is carried out. The parameters are set as follows: the mold temperature is raised to 185°C, the pressure is 12 MPa, and the treatment is carried out for 6 minutes. After the pressure holding treatment is completed, the mold temperature is lowered to below 60°C, the tableware is removed, and the edges are trimmed to obtain the finished product.

[0043] Comparative Example 1 The difference from Example 1 is that the treatment method of the wheat straw is adjusted, specifically, the wheat straw is not subjected to microbial pretreatment, and all other aspects are the same.

[0044] Comparative Example 2 The difference from Example 1 is that the microbial pretreatment method for wheat straw is adjusted, specifically, 0.005% of the dry weight of wheat straw is added as a composite microbial pretreatment agent, and the other aspects are the same.

[0045] Comparative Example 3 The difference from Example 1 is that the microbial pretreatment method of wheat straw is adjusted. Specifically, the composite microbial pretreatment agent is a mixed bacterial solution with a mass ratio of Bacillus subtilis solution: Bacillus cereus solution: Bacillus licheniformis solution: Bacillus pumilus solution: Bacillus amyloliquefaciens solution = 1:2:1:6:6, and the other methods are the same.

[0046] Comparative Example 4 The difference from Example 1 is that the microbial pretreatment method of wheat straw is adjusted. Specifically, the composite microbial pretreatment agent is a mixed bacterial solution of Bacillus cereus: Bacillus licheniformis: Bacillus pumilus at a mass ratio of 2:1:2, and Bacillus subtilis and Bacillus amyloliquefaciens are not added. All other conditions are the same.

[0047] Comparative Example 5 The difference from Example 2 is that the design of the tableware formula is adjusted, specifically, 10 parts of corn starch glue is used to replace 10 parts of modified soy protein glue, and everything else is the same.

[0048] Comparative Example 6 The difference from Example 2 is that the design of the tableware formula is adjusted, specifically, 10 parts of the commonly used adhesive polyvinyl alcohol is used to replace 10 parts of modified soy protein glue, and everything else is the same.

[0049] Comparative Example 7 The difference from Example 2 is that the design of the tableware formula is adjusted, specifically, nanocellulose is not added, and 3 parts of paraffin wax are used instead of 3 parts of palm wax, and everything else is the same.

[0050] Comparative Example 8 The difference from Example 2 is that the design of the tableware formula is adjusted, specifically, chitosan is not added, and everything else is the same.

[0051] Comparative Example 9 The difference from Example 2 is that the design of the tableware formula is adjusted, specifically, sodium carboxymethyl cellulose is not added, and everything else is the same.

[0052] Comparative Example 10 The difference from Example 2 is that the design of the tableware formula is adjusted, specifically, 1.5 parts of the common plasticizer glycerol is used instead of 1.5 parts of triethyl citrate, and all other aspects are the same.

[0053] The performance of the tableware prepared in the above examples and comparative examples was tested.

[0054] The physical properties and degradation performance of the prepared tableware were tested in accordance with the "General Technical Requirements for Disposable Degradable Tableware" (GB / T 18006.3-2020). The test results are shown in Tables 1 and 2, respectively. The antibacterial properties of the prepared tableware were tested in accordance with the "Determination of Antimicrobial Activity on the Surface of Plastics and Other Non-porous Materials" (GB / T 31402-2023). The test results are shown in Table 3.

[0055] Table 1. Physical property test results of tableware prepared in Examples 1-3 and Comparative Examples 1-10

[0056] As can be seen from Table 1, the load-bearing properties of the tableware manufactured in Examples 1-3 are all less than 2.0%, and the dropping, folding, heat resistance and waterproof capabilities are all good, indicating that the straw fiber-based fully degradable molded tableware prepared by the present invention has excellent performance and high quality.

[0057] It can be seen from Comparative Examples 1-4 that if the wheat straw is not pretreated with a composite microbial pretreatment agent or the pretreatment conditions are changed, the load-bearing performance, drop performance and folding performance of the resulting tableware are all poor. Among them, Comparative Example 1 does not undergo microbial pretreatment, resulting in insufficient degradation of wheat straw lignin, poor fiber flexibility, and reduced interfacial compatibility; Comparative Example 2 does not add a large amount of composite microbial pretreatment agent, resulting in the failure of the microbial community to form an effective metabolic network, partial hydrolysis of wheat straw hemicellulose but residual lignin, and insufficient fiber filamentation; Comparative Example 3 has an excessively large addition ratio of Bacillus pumilus and Bacillus amyloliquefaciens, resulting in excessive hydrolysis of wheat straw cellulose, uncoordinated lignin degradation, and an excessively high proportion of short fibers; Comparative Example 4 does not add Bacillus subtilis and Bacillus amyloliquefaciens, resulting in the failure of the wheat straw lignin-hemicellulose connection bond to break, the lack of biosurfactant, and low microbial colonization efficiency. The above treatment methods will all lead to a decrease in the fiber quality of the resulting wheat straw slurry, thereby affecting the physical properties of the resulting tableware.

[0058] From Comparative Examples 5-10, it can be seen that the physical properties of the tableware have declined to varying degrees by changing the tableware formula. The reason is speculated to be that Comparative Example 5 uses corn starch glue instead of modified soybean protein glue. The main component of corn starch glue is polysaccharide, which has weak hydrogen bonding and strong hydrophilicity. The molecular chain movement is aggravated at high temperature, making it difficult to maintain the integrity of the tableware structure, and the heat resistance and waterproof performance are poor; Comparative Example 6 uses polyvinyl alcohol instead of modified soybean protein glue. Polyvinyl alcohol is a water-soluble polymer. Although it has good adhesion, it is not heat-resistant enough. It cannot maintain structural stability in high-temperature use scenarios, which will also cause the heat resistance and waterproof performance of the tableware to deteriorate; Comparative Example 7 does not add nanocellulose, and uses paraffin wax instead of palm wax. The lack of nanocellulose weakens the "skeleton support" function of the material, and the high crystallinity of paraffin wax does not affect high-temperature molding. , but it reduces the bonding strength of the fiber-adhesive interface; in Comparative Example 8, no chitosan is added. Chitosan, as a natural polymer additive, has both bonding and toughening effects. Its absence leads to insufficient cohesion of the material and decreased deformation resistance; in Comparative Example 9, no sodium carboxymethyl cellulose is added. The "network skeleton" effect of sodium carboxymethyl cellulose can enhance the toughness of the material. Although the density of the material increases after its absence, the impact resistance is significantly reduced, which manifests as brittle fracture; in Comparative Example 10, glycerol is used instead of triethyl citrate. Triethyl citrate is a low-volatility plasticizer that can form hydrogen bonds with polymer chains through ester groups to maintain the flexibility of the material. However, the high volatility and strong hydrophilicity of glycerol prevent it from functioning stably in a high-temperature environment.

[0059] Table 2. Degradation performance test results of tableware prepared in Examples 1-3 and Comparative Examples 1-10

[0060] As can be seen from Table 2, the biodegradation rate, disintegration rate and ecotoxicity of the tableware manufactured in Examples 1-3 are far better than the standards and meet the full biodegradation standards.

[0061] It can be seen from Comparative Examples 1-4 that the wheat straw is not pretreated with microbial agents or the pretreatment conditions are not changed, resulting in insufficient pretreatment, ineffective degradation of lignin, and reduced biodegradability of the product. The biodegradation rate and disintegration rate of Comparative Example 3 are relatively good because the excessive hydrolysis of cellulose and hemicellulose accelerates the bioaccessibility of the material. Cellulose with low crystallinity and low polymerization degree is more easily attacked by cellulase secreted by environmental microorganisms, accelerating saccharification and decomposition, thereby increasing the biodegradation rate. Water-soluble sugars can be directly utilized by microorganisms, significantly improving the disintegration rate.

[0062] It can be seen from Comparative Examples 6-7 that the use of non-degradable ingredients (such as paraffin) or ingredients with a slow degradation rate (such as polyvinyl alcohol) in the tableware formula greatly affects the degradation performance of the product.

[0063] Table 3. Antibacterial performance test results of tableware prepared in Examples 1-3 and Comparative Examples 1-10

[0064] As can be seen from Table 3, the antibacterial rates of Examples 1-3 against Escherichia coli and Staphylococcus aureus are far superior to the standards, indicating that the tableware prepared by the present invention has excellent antibacterial effect.

[0065] It can be seen from Comparative Example 8 that due to the lack of chitosan in the tableware formula, the antibacterial performance of the product is significantly reduced, indicating that chitosan is the main antibacterial component.

Claims

1. Wheat straw fiber-based fully degradable molded product slurry, characterized in that: By weight Includes the following ingredients: 60-70 parts of wheat straw slurry, 8-10 parts of wheat bran, 8-12 parts of modified soy protein gum, 2-4 parts of palm wax, 3-5 parts of nanocellulose, 2-3 parts of chitosan, 1-2 parts of triethyl citrate, 2-4 parts of sodium carboxymethyl cellulose, and 8-10 parts of calcium sulfate.

2. The wheat straw fiber-based fully degradable molded product slurry according to claim 1, characterized in that: The wheat straw slurry is prepared according to the following method: Preparation: sorting the wheat straw raw materials, removing mildew and debris, and squeezing the raw materials; washing the wheat straw and drying it; soaking the dried wheat straw in water until it covers the straw; adding 1.1-1.5% sodium bicarbonate by weight of the water; mixing evenly; soaking and swelling for 24-48 hours; taking out the wheat straw to obtain the swollen wheat straw; adding 0.01-0.3% of the dry weight of the wheat straw to the swollen wheat straw; the composite microbial pretreatment agent The agent is prepared by compounding Bacillus subtilis solution, Bacillus cereus solution, Bacillus licheniformis solution, Bacillus pumilus solution and Bacillus amyloliquefaciens solution in a mass ratio of (1-3):(1-2):(1-3):(1-3):(1-3); adding water to cover the wheat straw, mixing evenly, fermenting and degrading at 35-40°C for 24-48 hours, taking out the wheat straw and drying it to obtain pretreated wheat straw, and grinding the pretreated wheat straw to prepare wheat straw slurry.

3. The wheat straw fiber-based fully degradable molded product slurry according to claim 2, characterized in that: Meet one or more of the following conditions: i. The number of viable cells of the Bacillus subtilis solution is 1.0×10 9 cfu / mL~1.0×10 11 cfu / mL, and the number of viable bacteria of Bacillus cereus liquid was 2.0×10 9 cfu / mL~5.0×10 10 cfu / mL, and the number of viable bacteria in the Bacillus licheniformis solution was 1.0×10 10 cfu / mL~5.0×10 11 cfu / mL, and the number of viable bacteria of Bacillus pumilus was 2.0×10 9 cfu / mL~ 1.0×10 11 cfu / mL, the number of viable bacteria of Bacillus amyloliquefaciens culture liquid was 1.0×10 9 cfu / mL~5.0×10 10 cfu / mL; ii. The Bacillus subtilis is Bacillus subtilis CICC 10028, the Bacillus cereus is Bacillus cereus CICC 10184, the Bacillus licheniformis is Bacillus licheniformis CICC 10084, the Bacillus pumilus is Bacillus pumilus CICC 22395, the Bacillus amyloliquefaciens is Bacillus amyloliquefaciens CICC 10160, all purchased from the China Industrial Microorganism Collection Center; iii. The refining is a two-stage refining, and the refining parameters are: coarse grinding, disc gap 0.5-1.5 mm, speed 1200-1500r / min, fiber length 1.5-2.0 mm; fine grinding, disc gap 0.15-0.25 mm, speed 2500-3000 r / min, fiber length 0.8-1.2 mm; iv. The moisture content of the wheat straw slurry obtained after refining is controlled to 8-12%.

4. The method for producing the wheat straw fiber-based fully degradable molded product slurry according to claim 1, characterized in that: The following steps are involved: The wheat straw slurry is evenly mixed with wheat bran, modified soybean protein glue, palm wax, nanocellulose, chitosan, triethyl citrate, sodium carboxymethyl cellulose and calcium sulfate to obtain wheat straw fiber-based fully degradable molding product slurry.

5. The manufacturing method according to claim 4, wherein: The ingredients are mixed in steps. The first step is to add nanocellulose to the straw slurry and disperse it by high-speed stirring. The second step is to add molten palm wax at 60-80°C and mix it at medium speed. The third step is to add modified soy protein gum and other ingredients and stir them at low speed to prevent foaming.

6. The manufacturing method according to claim 5, wherein: The high-speed stirring and dispersing condition is 1500 r / min stirring for 10 minutes; the medium-speed mixing condition is 800 r / min stirring for 5-10 minutes; and the low-speed stirring condition is 300 r / min stirring for 3-8 minutes.

7. Use of the wheat straw fiber-based fully degradable molded product slurry according to claim 1 in the preparation of molded products.

8. The use according to claim 7, characterized in that The molded products include tableware, egg trays, and cup trays.

9. The use according to claim 7, characterized in that The molded product is prepared by pressing and molding wheat straw fiber-based fully degradable molded product slurry.

10. The use according to claim 9, characterized in that The compression molding method comprises: using a quantitative feeder to deliver a slurry of a wheat straw fiber-based fully degradable molded product to a mold, setting the mold temperature and pressure, and using a three-stage hot press to compress the mixed material; after the pressing is completed, the mold temperature is lowered to below 60° C., the tableware is removed, and the molded product is obtained by trimming. Further preferably, the specific operation of the three-stage hot pressing is as follows: the first stage is a preheating stage, the mold temperature is raised to 90-110°C, the pressure is set to 2-5 MPa, the processing time is 1-3 minutes, and the water vapor is discharged after the end; The second stage is the main pressing stage, where the mold temperature is raised to 150-160°C, the pressure is set to 6-9 MPa, and the processing time is 8-12 minutes; The third stage is the pressure holding stage. The specific operation is: the mold temperature is raised to 170-190℃, the pressure is set to 10-12 MPa, and the processing time is 5-7 minutes.

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