High-load degradable light tray as well as preparation method and application thereof

Abstract

The invention relates to the technical field of degradable trays, in particular to a high-load degradable light tray and a preparation method and application thereof. The preparation method of the high-load degradable light tray comprises the following steps that a foaming raw material and a fluid foaming agent are mixed to form a mixture, the mixture is extruded through an extrusion technology to obtain a foaming material, the foaming raw material comprises a degradable material, and the foaming multiple of the foaming material is 30-70 times; degradable fibers are laid and attached to the interior of a mold cavity, the surface, away from the interior of the mold cavity, of the degradable fiber fabric is coated with an adhesive, the interior of the mold cavity where the degradable fiber fabric is laid and attached is filled with a foaming material, and the degradable light tray is obtained through an integrated forming technology. The degradation conditions of the degradable material and the degradable fiber are the same. According to the light tray formed by the degradable inner core and the shell through the integrated forming process, stress is fully released, and the bearing capacity of the tray is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of degradable pallets, and in particular to a high-load degradable lightweight pallet and a preparation method and application thereof. Background Art

[0002] With the rapid development of the modern supply chain, logistics pallets have evolved from the original simple wooden platforms to standard pallets that can meet the needs of mechanization. At present, traditional pallets mainly include wooden pallets, plywood pallets, plastic pallets, paper pallets or space pallets. Wooden pallets are of high quality and high price; plywood pallets are of high quality, poor strength and poor environmental performance; plastic pallets are non-degradable and have poor environmental performance; although paper pallets can be degraded, their load-bearing capacity is limited, and their strength decreases significantly after moisture absorption; space pallets can meet the requirements of lightweight and have excellent load-bearing capacity, but because they cannot be degraded, they are not environmentally friendly.

[0003] The prior art discloses a pallet and a preparation method thereof, which utilizes 100-200 parts of recycled polyethylene terephthalate (PET) powder, 15-20 parts of lubricant, 15-20 parts of calcium carbonate, 3-5 parts of foaming agent, 3-5 parts of antioxidant, 1-3 parts of glass fiber, and 2-6 parts of pH adjuster. The addition of glass fiber can enhance the rigidity, improve its mechanical properties and load-bearing capacity, but the maximum load-bearing capacity of the pallet can only reach 1500kg, and the load-bearing effect is not ideal. Moreover, the pallet cannot achieve integrated degradation, resulting in the continued existence of the hazards of microplastics. Summary of the invention

[0004] Therefore, in order to solve the above technical problems, the present invention provides a high-load-bearing degradable lightweight pallet and a preparation method and application thereof.

[0005] The present invention provides a preparation method of a high-load-bearing degradable lightweight pallet, comprising the following steps: mixing a foaming raw material and a fluid foaming agent to form a mixture, extruding the mixture through an extrusion process to obtain a foamed material, wherein the foaming raw material comprises a degradable material, and the foaming multiple of the foamed material is 30-70 times; paving degradable fibers inside a mold cavity, coating an adhesive on a surface of the degradable fiber fabric away from the inside of the mold cavity, filling the foaming material into the mold cavity paved with the degradable fiber fabric, and obtaining a degradable lightweight pallet through an integrated molding process; the degradation conditions of the degradable material and the degradable fibers are the same.

[0006] In some embodiments, the degradable fiber includes at least one of a degradable felt or a degradable fiber fabric.

[0007] In some of these embodiments, the one-piece forming process includes a steam molding process.

[0008] In some embodiments, the degradable material comprises a biodegradable material.

[0009] In some embodiments, the foaming raw material also includes at least one of a first cellulose and talcum powder. The mass ratio of the degradable material, the first cellulose and the talcum powder in the foaming raw material is 100:3-5:2-5. Preferably, the foaming raw material is obtained by forming a mixture of the first cellulose and talcum powder, and then mixing the mixture with the degradable material; the first cellulose and talcum powder are mixed by ball milling, the rotation speed of the ball mill is 200-800rpm, and the ball milling time is 0.5-6h; the mixing temperature of the mixture and the degradable material is 130-180℃, and the mixing time is 6-24h.

[0010] In some embodiments, the first cellulose includes at least one of bamboo powder fiber and bagasse fiber, and the particle size of the first cellulose is greater than or equal to 400 mesh, preferably 600-1000 mesh.

[0011] In some embodiments, the biodegradable material comprises at least one of polylactic acid, polyglycolic acid, polyhydroxyalkanoate, polysaccharide, protein, polyethylene terephthalate, polybutylene succinate, wherein the polysaccharide comprises at least one of starch or a second cellulose. Preferably, the biodegradable material is polylactic acid.

[0012] In some of these embodiments, the fluid foaming agent includes at least one of carbon dioxide and nitrogen.

[0013] In some embodiments, the foamed material includes at least one of a cylinder and an olive shape.

[0014] Preferably, in some embodiments, when the foaming material is a cylinder, the diameter of the cylinder is 1-10 mm and the height is 1-10 mm.

[0015] In some embodiments, the foaming raw material is mixed with the fluid foaming agent including supercritical carbon dioxide.

[0016] When the first mixture and the fluid foaming agent are mixed by means of supercritical carbon dioxide, the supercritical fluid foaming agent is continuously introduced into the system and the internal pressure is controlled to achieve mixing.

[0017] In some embodiments, the foaming multiple of the foaming material is 40-70 times.

[0018] In some embodiments, the extrusion process includes using a die with a preheating temperature of 180-295° C. and extruding the foaming material at a rotation speed of 40-55 rpm. Preferably, the preheating temperature of the die is 185-195° C. and the rotation speed is 50-55 rpm.

[0019] In some embodiments, the material of the degradable fiber fabric includes at least one of polylactic acid fiber, polyglutamic acid fiber, polyhydroxyalkanoate fiber, polyhydroxyalkanoate fiber, polybutylene adipate terephthalate, polysaccharide fiber, protein fiber, and polyglycolic acid fiber, wherein the polysaccharide fiber includes at least one of starch-based fiber, chitin fiber or plant fiber.

[0020] In some embodiments, the surface density of the degradable fiber fabric is 60-400 g / m 2 , preferably 100-300g / m 2 , thickness is 0.3mm-0.8mm.

[0021] In some embodiments, the degradable fiber fabric includes at least one of a twill fabric or a patterned fabric.

[0022] In some of the embodiments, a degradable hot-melt adhesive is coated between the degradable fiber fabric and the foaming raw material, and the raw material of the degradable hot-melt adhesive includes polylactic acid.

[0023] In some of the embodiments, before laying the degradable fiber inside the mold cavity, a step of coating the inside of the mold cavity with a silane coupling agent is also included.

[0024] In some of the embodiments, when the degradation condition is industrial composting, the degradable material includes at least one of polylactic acid, starch-based foaming material, polybutylene adipate terephthalate foaming material, polyhydroxyalkanoate, polyhydroxyalkanoate, polyglycolic acid, cellulose-based foaming material, and polybutylene succinate; the material of the degradable fiber fabric includes at least one of polylactic acid fiber, polyhydroxyalkanoate fiber, polyhydroxyalkanoate fiber, polybutylene adipate terephthalate fiber, starch-based composite fiber, chitin fiber or polyglycolic acid; further, the material of the degradable fiber fabric includes compostable degradable coated fabric.

[0025] In some of the embodiments, when the degradation conditions are wet anaerobic digestion degradation, the degradable material includes at least one of polylactic acid, starch-based foaming material, polyhydroxyalkanoate, cellulose-based foaming material, protein-based foaming material, and polybutylene succinate, and the material of the degradable fiber fabric includes at least one of polylactic acid fiber, polyhydroxyalkanoate fiber, polybutylene terephthalate fiber, starch-based composite fiber, protein-based fiber, and plant fiber.

[0026] On the other hand, the present invention provides a high-load-bearing, degradable, lightweight pallet produced by the above-mentioned preparation method. The pallet provided by the present invention can be applied in logistics transportation or offshore photovoltaic power stations.

[0027] The technical solution of the present invention has the following advantages:

[0028] The present invention provides a method for preparing a high-load degradable lightweight pallet, comprising the following steps: mixing a foaming raw material and a fluid foaming agent to form a mixture, extruding the mixture by an extrusion process to obtain a foamed material, wherein the foaming raw material includes a degradable material, and the foaming multiple of the foamed material is 30-70 times; paving the degradable fiber inside the mold cavity, coating the surface of the degradable fiber fabric away from the inside of the mold cavity with an adhesive, filling the foaming raw material into the mold cavity paved with the degradable fiber fabric, and obtaining a degradable lightweight pallet by an integrated molding process; the degradation conditions of the degradable material and the degradable fiber are the same. The present invention uses an integrated molding process to form a lightweight pallet with a degradable inner core and an outer shell, which has sufficient stress release, high pallet strength, and improved pallet bearing capacity.

[0029] The invention limits the foaming multiple of the foaming material to 30-70 times, thereby significantly improving the load-bearing capacity of the pallet and increasing the ultimate breaking load to more than 4000kg.

[0030] The present invention coats a degradable hot-melt adhesive between the degradable fiber fabric and the foaming raw material, thereby not only improving the adhesion between the outer shell and the inner core and further improving the strength of the pallet, but also ensuring that the adhesive and the pallet are completely degraded under the same degradation conditions, thereby improving environmental protection performance.

[0031] Furthermore, the present invention selects materials with the same degradation conditions as the inner core and the outer shell, respectively, so that the pallet can be completely degraded under the same degradation conditions without having to be disassembled and processed separately, thereby simplifying the degradation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 Schematic diagram of the mold cavity laying the outer shell knitted product in Example 1 of the present invention;

[0034] Reference numerals:

[0035] 1-Inside of the mold cavity; 2-Outer shell textile; 3-Degradable adhesive. DETAILED DESCRIPTION

[0036] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the guidance of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0037] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

[0038] Example 1

[0039] This embodiment provides a method for preparing a high-load-bearing degradable lightweight pallet, and the specific steps and parameters are as follows:

[0040] (1) According to the mass ratio of bamboo powder fiber particles to talcum powder of 3:2, bamboo powder fiber particles (particle size of 800 mesh) and talcum powder are ball-milled in a sodium hydroxide aqueous solution to form a mixture. After sieving, the mixture and polylactic acid (Zhejiang Hisun Biomaterials, REVODE110 weight average molecular weight 196200Da) are added to an internal mixer according to the mass ratio of the mixture to polylactic acid of 5:100, and kneaded at 150°C for 6 hours to obtain a first mixed masterbatch.

[0041] (2) Fluid foaming agent carbon dioxide is introduced into the first mixture masterbatch at a pressure of 5.5 MPa, and the first mixture and the fluid foaming agent are fully mixed by supercritical CO2 fluid until a constant pressure reaches 8.4 MPa to obtain a second mixture.

[0042] (3) The second mixed material is extruded by a twin-screw continuous extrusion process, wherein the specific steps are as follows: the second mixed material is extruded continuously at a rotation speed of 50 rpm in an extruder preheated at 180° C., the die head uses a diameter of 1.2 mm, and the cylindrical foamed beads with a diameter of 3 mm and a height of 3 mm are obtained by continuous cutting. The foamed beads have a foaming ratio of 40-45 times and a closed cell rate of more than 98%.

[0043] (4) Preheat the mold at 100°C and apply 10 g of silane coupling agent KH-550 (γ-aminopropyltriethoxysilane, brand SG-Si1100, CAS number 919-30-2, purchased from Nanjing Shuguang Chemical Group Co., Ltd.) to the inside of the mold cavity. Figure 1 As shown, the pre-cut shell textile 2 is laid inside the mold cavity 1, and the degradable adhesive 3 is coated on the surface of the textile away from the inside of the mold cavity, with a total of 50g of adhesive applied on both sides (the adhesive is a polylactic acid hot melt adhesive with a molecular weight of 3000Da). The surface density of the shell textile is 200g / m2 , a polylactic acid fiber twill fabric with a thickness of 0.6 mm, the foamed beads obtained in step (3) are filled into the mold cavity paved with the shell textile, and a steam molding process is adopted to form the foamed beads. The specific steps are as follows: fill the mold cavity with the beads, back-blow the beads, close the mold and compress, the compression amount is 10 mm of the compression gap reserved for the mold, first heat the non-planar side of the mold, the steam pressure is 1.2 bar, the heating time is 20 seconds, then heat the planar side, the steam pressure is 1.1 bar, the heating time is 17 seconds, and finally heat both sides at the same time, the steam pressure is 1.2 bar, the heating time is 10 seconds, cool, demould, dry, and trim to obtain an integrally formed tray.

[0044] Example 2

[0045] This embodiment provides a method for preparing a high-load-bearing biodegradable lightweight pallet. The specific steps and parameters are the same as those in Example 1, except that an equal mass of polybutylene terephthalate (weight-average molecular weight of 50,000) is used to replace the polylactic acid in step (1).

[0046] Example 3

[0047] This embodiment provides a method for preparing a high-load-bearing degradable lightweight pallet. The specific steps and parameters are the same as those in Example 1, except that an equal mass of protein-based foaming material is used to replace the polylactic acid in step (1).

[0048] Example 4

[0049] This embodiment provides a method for preparing a high-load-bearing biodegradable lightweight pallet. The specific steps and parameters are the same as those in Example 1, except that an equal mass of poly-β-hydroxybutyric acid (weight-average molecular weight of 3,000,000 Da) is used to replace the polylactic acid in step (1).

[0050] Example 5

[0051] The present embodiment provides a method for preparing a high-load-bearing biodegradable lightweight pallet. The specific steps and parameters are the same as those in Example 1, except that the foaming ratio of the foamed beads is 50-60 times, and the extrusion process parameters are preheating the die head to 185°C and continuous extrusion and foaming at a rotation speed of 50 rpm.

[0052] Example 6

[0053] The present embodiment provides a method for preparing a high-load-bearing biodegradable lightweight pallet. The specific steps and parameters are the same as those in Example 1, except that the foaming ratio of the foamed beads is 60-70 times, and the extrusion process parameters are preheating the die head at 195°C and continuous extrusion and foaming at a rotation speed of 55 rpm.

[0054] Example 7

[0055] This embodiment provides a method for preparing a high-load-bearing biodegradable lightweight pallet. The specific steps and parameters are the same as those in Example 1, except that the foaming ratio of the foamed beads is 30-40 times, and the extrusion process parameters are preheating the die head to 180°C and continuous extrusion and foaming at a rotation speed of 40 rpm.

[0056] Example 8

[0057] This embodiment provides a method for preparing a high-load-bearing degradable lightweight pallet, and the specific steps and parameters are as follows:

[0058] (1) According to the mass ratio of bamboo powder fiber particles to talcum powder of 3:5, bamboo powder fiber particles (particle size of 800 mesh) and talcum powder are ball-milled in a sodium hydroxide aqueous solution to form a mixture, and after screening, the mixture and polybutylene adipate terephthalate foaming material are added into an internal mixer according to the mass ratio of 8:100, and kneaded at 150° C. for 8 hours to obtain a first mixed masterbatch.

[0059] (2) Fluid foaming agent nitrogen is introduced into the first mixed material masterbatch at a pressure of 5.5 MPa, and the first mixed material and the fluid foaming agent are fully mixed by supercritical CO2 fluid to obtain a second mixed material.

[0060] (3) The second mixed material is extruded by a twin-screw continuous extrusion process, wherein the specific steps are as follows: the second mixed material is extruded continuously at a rotation speed of 50 rpm in an extruder preheated at 180° C., the die head uses a diameter of 1.2 mm, and the cylindrical foamed beads with a diameter of 5 mm and a height of 10 mm are obtained by continuous cutting. The foaming ratio of the foamed beads is 45-50 times, and the closed cell rate is more than 95%.

[0061] (4) Preheat the mold at 100°C, apply 10 g of silane coupling agent KH-550 (γ-aminopropyltriethoxysilane, brand SG-Si1100, CAS number 919-30-2, purchased from Nanjing Shuguang Chemical Group Co., Ltd.) inside the mold cavity, lay the pre-cut shell textile into the mold cavity, and apply a degradable adhesive on the surface of the textile away from the mold cavity, with a total of 50 g of adhesive applied on both sides (the adhesive is a polylactic acid hot melt adhesive with a molecular weight of 3000 Da). The surface density of the shell textile is 200 g / m 2, a poly-β-hydroxybutyric acid twill fabric with a thickness of 0.6 mm, filling the foamed beads obtained in step (3) into the mold cavity paved with the shell textile, and adopting a steam molding process to form. The specific steps are as follows: fill the mold cavity with the beads, back-blow the beads, close the mold and compress, the compression amount is 10 mm of the compression seam reserved for the mold, first heat the non-planar side of the mold, the steam pressure is 1.2 bar, the heating time is 20 seconds, then heat the flat side, the steam pressure is 1.1 bar, the heating time is 17 seconds, and finally heat both sides at the same time, the steam pressure is 1.2 bar, the heating time is 10 seconds, cool, demould, dry, and trim to obtain an integrally formed tray.

[0062] Example 9

[0063] This embodiment provides a method for preparing a high-load-bearing degradable lightweight pallet, and the specific steps and parameters are as follows:

[0064] (1) According to the mass ratio of bamboo powder fiber particles to talcum powder of 5:2, bamboo powder fiber particles (particle size of 800 mesh) and talcum powder are ball-milled in a sodium hydroxide aqueous solution to form a mixture, and after screening, the mixture and the starch-based foaming material are added to an internal mixer according to the mass ratio of the mixture to the starch-based foaming material of 7:100, and kneaded at 150° C. to obtain a first mixed masterbatch.

[0065] (2) Fluid foaming agent nitrogen is introduced into the first mixed material masterbatch at a pressure of 5.5 MPa, and the first mixed material and the fluid foaming agent are fully mixed by supercritical CO2 fluid until a constant pressure reaches 8.4 MPa to obtain a second mixed material.

[0066] (3) The second mixed material is extruded by a twin-screw continuous extrusion process, wherein the specific steps are as follows: the second mixed material is extruded continuously at a rotation speed of 50 rpm in an extruder preheated at 180° C., the die head uses a diameter of 1.2 mm, and the cylindrical foamed beads with a diameter of 10 mm and a height of 3 mm are obtained by continuous cutting. The foaming ratio of the foamed beads is 50-55 times, and the closed cell rate is more than 95%.

[0067] (4) Preheat the mold at 100°C, apply 10 g of silane coupling agent KH-550 (γ-aminopropyltriethoxysilane, brand SG-Si1100, CAS number 919-30-2, purchased from Nanjing Shuguang Chemical Group Co., Ltd.) inside the mold cavity, lay the pre-cut shell textile into the mold cavity, and apply a degradable adhesive on the surface of the textile away from the mold cavity, with a total of 50 g of adhesive applied on both sides (the adhesive is a polylactic acid hot melt adhesive with a molecular weight of 3000 Da). The surface density of the shell textile is 200 g / m 2, polybutylene adipate terephthalate with a thickness of 0.6 mm, filling the foamed beads obtained in step (3) into the mold cavity paved with the shell textile, and adopting a steam molding process to form. The specific steps are as follows: fill the mold cavity with the beads, back-blow the beads, close the mold and compress, the compression amount is 10 mm of the compression gap reserved for the mold, first heat the non-planar side of the mold, the steam pressure is 1.2 bar, the heating time is 20 seconds, then heat the flat side, the steam pressure is 1.1 bar, the heating time is 17 seconds, and finally heat both sides at the same time, the steam pressure is 1.2 bar, the heating time is 10 seconds, cool, demould, dry, and trim to obtain an integrally formed tray.

[0068] Comparative Example 1

[0069] This comparative example provides a method for preparing a high-load-bearing biodegradable lightweight pallet. The specific steps and parameters are the same as those in Example 1, except that polyethylene terephthalate fiber fabric is used instead of the polylactic acid fiber fabric in step (4) of Example 1.

[0070] Comparative Example 2

[0071] This comparative example provides a method for preparing a high-load-bearing biodegradable lightweight pallet. The specific steps and parameters are the same as those in Example 1, except that the pallet is not formed in one piece. The specific steps are: filling the foamed beads prepared in step (3) into a mold, forming an inner core by a steam molding process, and adhering the inner core to the outer shell sheet formed by vacuum forming by applying an adhesive to form a pallet.

[0072] Comparative Example 3

[0073] This comparative example provides a method for preparing a high-load-bearing degradable lightweight pallet, and the specific steps and parameters are the same as those of Example 1, except that step (4) does not include the step of coating the degradable adhesive on the surface of the outer shell knitted fabric away from the inside of the mold cavity.

[0074] Comparative Example 4

[0075] This embodiment provides a method for preparing a high-load-bearing biodegradable lightweight pallet. The specific steps and parameters are the same as those in Example 1, except that the foaming ratio of the foamed beads is 70-80 times, and the extrusion process parameters are preheating the die head at 200°C and continuous extrusion and foaming at a rotation speed of 60rpm.

[0076] Experimental Example 1

[0077] The degradation effects of the pallets formed in Examples 1-11 and Comparative Example 1 were measured, and the measurement results are shown in Table 1.

[0078] The method for determining the degradation effect is as follows: GB / T 19277.2-2013 "Standard for Determination of the Final Aerobic Biodegradability of Materials under Controlled Composting Conditions" is used to determine the industrial composting degradation effect; GB / T38737-2020 "Determination of the Final Anaerobic Biodegradability of Materials in a Controlled Sludge Digestion System of Plastics by Measuring the Release of Biogas" is used to determine the wet anaerobic digestion degradation effect.

[0079] It has been determined that the pallet provided in Example 1 of the present invention can achieve complete degradation of the pallet within 30 days under the conditions of industrial composting, the pallet provided in Example 3 can achieve complete degradation of the pallet within 30 days under the conditions of wet anaerobic digestion, and the pallets provided in Examples 2 and Examples 4-10 can all meet the requirement of complete degradation within 6 months under the conditions of industrial composting, while the pallet provided in Comparative Example 1 cannot meet the requirement of complete degradation within 6 months under the conditions of industrial composting, and cannot achieve sufficient degradation of the pallet.

[0080] Experimental Example 2

[0081] The quality and load-bearing effect of the pallets formed in Examples 1-7 and Comparative Examples 2-4 were measured respectively. The measurement results are shown in Table 1.

[0082] The method for measuring the load-bearing effect is as follows: the pallet is statically loaded with 1800kg and maintained for 24 hours. Then, the pallet is dynamically loaded with 500kg at a moving speed of 20cm / s and maintained for 1 hour, and the deformation of the pallet is measured.

[0083] The ultimate breaking test method is as follows: use a pressure plate that simulates the actual load to uniformly load the pallet (loading rate ≤ 10mm / min), record the load-displacement curve until the pallet structure breaks, and record the maximum breaking load.

[0084] Table 1 Pallet quality and load-bearing effect

[0085] quality Deformation mm Ultimate breaking load kg Example 1 4.2kg 3 4100 Example 2 4.4kg 2 4000 Example 3 4.0kg 5 3700 Example 4 4.2kg 3 3300 Example 5 3.8kg 5 3200 Example 6 3.5kg 6 3000 Example 7 5.0kg 3 4500 Comparative Example 2 4.2kg 6 3000 Comparative Example 3 4.4kg 6 2000 Comparative Example 4 3.1kg 14 2000

[0086] According to Table 2, compared with the pallets provided in Comparative Examples 2-4 with a load-bearing deformation greater than or equal to 6 mm and an ultimate breaking load of less than 3000 kg, the pallet provided in the embodiment of the present invention has a load-bearing deformation of 2-6 mm and an ultimate breaking load of more than 3000 kg, which proves that the pallet provided by the present invention has good load-bearing capacity; and in Example 7, the pallet formed by foamed beads with a foaming ratio of 30-40 times is relatively heavy, and the pallet formed by foamed beads with a foaming ratio of 40-70 times is relatively light.

[0087] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A method for preparing a high-load-bearing degradable lightweight pallet, characterized in that: The following steps are included: Mixing a foaming raw material and a fluid foaming agent to form a mixture, and extruding the mixture by an extrusion process to obtain a foaming material, wherein the foaming raw material includes a degradable material, and the foaming multiple of the foaming material is 30-70 times; The degradable fiber is laid inside the mold cavity, an adhesive is applied to the surface of the degradable fiber fabric away from the inside of the mold cavity, a foaming material is filled into the mold cavity where the degradable fiber fabric is laid, and a degradable lightweight pallet is obtained by an integrated molding process; The degradation conditions of the degradable material and the degradable fiber are the same.

2. The method for preparing a high-load-bearing degradable lightweight pallet according to claim 1, characterized in that: The degradable fiber comprises at least one of a degradable felt or a degradable fiber fabric; and / or, The one-piece molding process includes a steam molding process; and / or, The degradable material includes a biodegradable material.

3. The method for preparing a high-load-bearing degradable lightweight pallet according to claim 2, characterized in that: The foaming raw material further comprises at least one of a first cellulose and talc; and / or, The biodegradable material comprises at least one of polylactic acid, polyglycolic acid, polyhydroxyalkanoate, polysaccharide, protein, polyethylene terephthalate, and polybutylene succinate, wherein the polysaccharide comprises at least one of starch or a second cellulose; and / or, The fluid blowing agent includes at least one of carbon dioxide and nitrogen.

4. The method for preparing a high-load-bearing degradable lightweight pallet according to claim 3, characterized in that: The biodegradable material is polylactic acid; and / or, The first cellulose includes at least one of bamboo powder fiber and bagasse fiber; and / or, The foaming material comprises at least one of a cylindrical shape or an olive shape; and / or, The foaming raw material is mixed with the fluid foaming agent in a manner that includes supercritical carbon dioxide.

5. The method for preparing a high-load-bearing degradable lightweight pallet according to claim 4, characterized in that: The foaming multiple of the foaming material is 40-70 times; and / or, When the foaming material is a cylinder, the diameter of the cylinder is 1-10 mm and the height is 1-10 mm; and / or, The extrusion process comprises using a die head with a preheating temperature of 180-295° C. and extruding the foaming material at a rotation speed of 40-55 rpm. Preferably, the preheating temperature of the die head is 185-195° C. and the rotation speed is 50-55 rpm; and / or, The material of the degradable fiber fabric includes at least one of polylactic acid fiber, polyglutamic acid fiber, polyhydroxyalkanoate fiber, polyhydroxyalkanoate fiber, polybutylene adipate terephthalate, polysaccharide fiber, protein fiber, and polyglycolic acid fiber, wherein the polysaccharide fiber includes at least one of starch-based fiber, chitin fiber, or plant fiber.

6. The method for preparing a high-load-bearing degradable lightweight pallet according to claim 1, characterized in that: The surface density of the degradable fiber fabric is 60-400g / m 2 , preferably 100-300g / m 2 , with a thickness of 0.3 mm to 0.8 mm; and / or, The degradable fiber fabric includes at least one of a twill fabric or a patterned fabric.

7. The method for preparing a high-load-bearing degradable lightweight pallet according to claim 1, characterized in that: A degradable hot melt adhesive is coated between the degradable fiber fabric and the foaming raw material, and the raw material of the degradable hot melt adhesive includes polylactic acid; Before the degradable fiber is laid inside the mold cavity, the method also includes a step of coating the inside of the mold cavity with a silane coupling agent.

8. The method for preparing a high-load-bearing degradable lightweight pallet according to claim 3, characterized in that: When the degradation condition is industrial composting, the degradable material includes at least one of polylactic acid, starch-based foaming material, polybutylene adipate terephthalate foaming material, polyhydroxyalkanoate, polyhydroxyalkanoate, polyglycolic acid, cellulose-based foaming material, and polybutylene succinate, and the material of the degradable fiber fabric includes at least one of polylactic acid fiber, polyhydroxyalkanoate fiber, polyhydroxyalkanoate fiber, polybutylene adipate terephthalate fiber, starch-based composite fiber, chitin fiber, polyglycolic acid or; When the degradation condition is wet anaerobic digestion degradation, the degradable material includes at least one of polylactic acid, starch-based foaming material, polyhydroxyalkanoate, cellulose-based foaming material, protein-based foaming material, and polybutylene succinate, and the material of the degradable fiber fabric includes at least one of polylactic acid fiber, polyhydroxyalkanoate fiber, polybutylene adipate terephthalate fiber, starch-based composite fiber, protein-based fiber, and plant fiber.

9. A high-load-bearing, degradable, lightweight pallet, characterized in that: The pallet is prepared by the method for preparing a high-load-bearing degradable lightweight pallet as described in any one of claims 1 to 8.

10. Use of the high-load-bearing, degradable, lightweight pallet according to claim 9 in logistics transportation or offshore photovoltaic power stations.

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