Preparation method of degradable composite woven bag

Abstract

The invention relates to the field of composite woven bags, in particular to a preparation method of a degradable composite woven bag. Comprising the following raw materials in parts by mass: 50-100 parts of degradable plastic, 5-10 parts of a plasticizer, 10-15 parts of calcium carbonate, 10-20 parts of silicon dioxide, 3-7 parts of a coupling agent, 2-4 parts of zinc chloride, 5-7 parts of an antioxidant, 5-10 parts of a light stabilizer, 10-20 parts of chitosan, 15-25 parts of a toughness additive, 30-40 parts of starch polyvinyl alcohol, 15-25 parts of a carbon dioxide copolymer and 10-15 parts of aliphatic aromatic copolyester. And 100 to 200 parts of kraft paper. By adding the degradable plastic, the toughness additive, the starch polyvinyl alcohol, the carbon dioxide copolymer and the aliphatic aromatic copolyester, various properties of the composite plastic bag can be improved, and the normal degradation property of the composite plastic bag cannot be influenced, so that the composite plastic bag is relatively environment-friendly, and the influence of the composite plastic bag on the environment is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of composite woven bags, and in particular to a method for preparing a degradable composite woven bag. Background Art

[0002] Composite woven bags are made by compounding woven bags with other materials. It combines the lightness, easy processing and low cost of woven bags with the strength, waterproofness, UV resistance and load-bearing capacity of composite materials.

[0003] At present, traditional composite woven bags on the market are usually made of plastic and other materials. If the materials are not degradable, they will exist in the natural environment for a long time and are not easily decomposed by microorganisms. This will lead to soil pollution and water pollution, because non-degradable composite woven bags will release harmful substances in the environment, affecting the ecological balance of soil and water. Therefore, a method for preparing a degradable composite woven bag is urgently needed. Summary of the invention

[0004] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a method for preparing a degradable composite woven bag.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for preparing a degradable composite woven bag, comprising the following raw materials in parts by weight:

[0007] 50-100 parts of degradable plastic, 5-10 parts of plasticizer, 10-15 parts of calcium carbonate, 10-20 parts of silicon dioxide, 3-7 parts of coupling agent, 2-4 parts of zinc chloride, 5-7 parts of antioxidant, 5-10 parts of light stabilizer, 10-20 parts of chitosan, 15-25 parts of toughness additive, 30-40 parts of starch polyvinyl alcohol, 15-25 parts of carbon dioxide copolymer, 10-15 parts of aliphatic aromatic copolyester, 100-200 parts of kraft paper;

[0008] A method for preparing a degradable composite woven bag based on the above raw materials comprises the following steps:

[0009] S1: Pour 50-100 parts of biodegradable plastic, 30-40 parts of starch polyvinyl alcohol, 15-25 parts of carbon dioxide copolymer and 10-15 parts of aliphatic aromatic copolyester into a reactor for reaction;

[0010] S2: After the reaction is completed, the above raw materials are taken out and poured into a mixer, and then 5-10 parts of plasticizer, 10-15 parts of calcium carbonate, 10-20 parts of silicon dioxide, 3-7 parts of coupling agent, 2-4 parts of zinc chloride, 5-7 parts of antioxidant, 5-10 parts of light stabilizer, 10-20 parts of chitosan and 15-25 parts of toughness additive are added into the mixer and stirred;

[0011] S3: After the stirring is completed, the above materials are taken out and poured into a multi-layer co-extrusion extruder for film forming;

[0012] S4: Put the film-formed material into a compounding machine and add 100-200 parts of kraft paper for compounding;

[0013] S5: Use a bag making machine to cut and seal the composite material to make a plastic bag;

[0014] S6: Pack the prepared plastic bag.

[0015] Preferably, the degradable plastic is prepared by mixing polylactic acid, polycaprolactone and polyhydroxyalkanoate, wherein the weight ratio of polylactic acid, polycaprolactone and polyhydroxyalkanoate is (1-3):2:(3-5).

[0016] Preferably, the toughness additive is prepared by copolymerization of polybutylene succinate and terephthalate, wherein the weight ratio of polybutylene succinate to terephthalate is (2-4): (5-7).

[0017] Preferably, the starch polyvinyl alcohol is prepared by mixing starch and polyvinyl alcohol, wherein the weight ratio between starch and polyvinyl alcohol is 1:3.

[0018] Preferably, the carbon dioxide copolymer comprises carbon dioxide, propylene oxide and succinic anhydride, which are polymerized by catalytic reaction, wherein the weight ratio of carbon dioxide, propylene oxide and ethylene oxide is 1:(20-30):(20-30).

[0019] Preferably, the aliphatic aromatic copolyester is formed by polymerization of adipic acid, sebacic acid and polybutylene terephthalate via a catalytic reaction, wherein the weight ratio of adipic acid, sebacic acid and polybutylene terephthalate is (3-5):(2-4):(1-3).

[0020] Preferably, the stirring rate in the reactor in step S1 is 100-200 rpm, the reaction temperature is 500-700° C., and the reaction time is 5-7 h.

[0021] Preferably, the stirring rate in the mixer in step S2 is 200-300 rpm, the reaction temperature is 700-900° C., and the reaction time is 3-5 h.

[0022] Preferably, the multi-layer co-extrusion extruder has a screw diameter of 30-50 mm, an extrusion speed of 50-100 m / min, a screw speed of 600-700 rpm, and is provided with 4 temperature zones.

[0023] The beneficial effects of the present invention are as follows: by adding degradable plastics, toughness additives, starch polyvinyl alcohol, carbon dioxide copolymers and aliphatic aromatic copolyesters, not only can the various properties of the composite plastic bag be improved, but also its normal degradation performance will not be affected, which is more environmentally friendly and reduces the impact of the composite plastic bag on the environment. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0025] Embodiment 1:

[0026] A method for preparing a degradable composite woven bag, comprising the following raw materials in parts by weight:

[0027] 50 parts of biodegradable plastic, 5 parts of plasticizer, 10 parts of calcium carbonate, 10 parts of silicon dioxide, 3 parts of coupling agent, 2 parts of zinc chloride, 5 parts of antioxidant, 5 parts of light stabilizer, 10 parts of chitosan, 15 parts of toughness additive, 30 parts of starch polyvinyl alcohol, 15 parts of carbon dioxide copolymer, 10 parts of aliphatic aromatic copolyester, 100 parts of kraft paper;

[0028] A method for preparing a degradable composite woven bag based on the above raw materials comprises the following steps:

[0029] S1: Pour 50 parts of biodegradable plastic, 30 parts of starch polyvinyl alcohol, 15 parts of carbon dioxide copolymer and 10 parts of aliphatic aromatic copolyester into a reactor for reaction;

[0030] S2: After the reaction is completed, the above raw materials are taken out and poured into a mixer, and then 5 parts of plasticizer, 10 parts of calcium carbonate, 10 parts of silicon dioxide, 3 parts of coupling agent, 2 parts of zinc chloride, 5 parts of antioxidant, 5 parts of light stabilizer, 10 parts of chitosan and 15 parts of toughness additive are added into the mixer and stirred;

[0031] S3: After the stirring is completed, the above materials are taken out and poured into a multi-layer co-extrusion extruder for film forming;

[0032] S4: Put the film-formed material into a compounding machine and add 100 parts of kraft paper for compounding;

[0033] S5: Use a bag making machine to cut and seal the composite material to make a plastic bag;

[0034] S6: Pack the prepared plastic bag.

[0035] Degradable plastics are made by mixing polylactic acid, polycaprolactone and polyhydroxyalkanoates, in which the weight ratio of polylactic acid, polycaprolactone and polyhydroxyalkanoates is 1:2:3. Polylactic acid can be gradually degraded at high temperatures and eventually converted into carbon dioxide and water, which is environmentally friendly. Polycaprolactone is also a biodegradable plastic, which degrades slowly but can be gradually degraded under high temperature and the action of microorganisms. Polyhydroxyalkanoates are another type of biodegradable plastic that can be degraded under a variety of environmental conditions, including high temperature and humid environments. The degradable plastics formed by mixing and copolymerizing them not only have good degradation performance, but also have high strength.

[0036] The toughness additive is prepared by copolymerization of polybutylene succinate and terephthalate, wherein the weight ratio of polybutylene succinate to terephthalate is 2: 5. By adding the toughness additive, the toughness of the composite woven bag can be further improved without affecting its degradation performance and shape.

[0037] Among them, starch polyvinyl alcohol is prepared by mixing starch and polyvinyl alcohol, wherein the weight ratio between starch and polyvinyl alcohol is 1:3. Starch polyvinyl alcohol combines the advantages of starch and polyvinyl alcohol, and has good biodegradability and certain physical properties. It can be used to improve the barrier properties of plastic bags and reduce costs.

[0038] The carbon dioxide copolymer is formed by the polymerization of carbon dioxide, propylene oxide and succinic anhydride through catalytic reaction, wherein the weight ratio of carbon dioxide, propylene oxide and ethylene oxide is 1:20:20. The carbon dioxide copolymer formed by the polymerization of carbon dioxide, propylene oxide and succinic anhydride through catalytic reaction not only has good degradation performance and barrier performance, but also has the advantages of transparency and non-toxicity.

[0039] Among them, the aliphatic aromatic copolyester includes adipic acid, sebacic acid and polybutylene terephthalate through catalytic polymerization, wherein the weight ratio of adipic acid, sebacic acid and polybutylene terephthalate is 3:2:1. The aliphatic aromatic copolyester formed by the catalytic polymerization of adipic acid, sebacic acid and polybutylene terephthalate has an excellent structure, and has excellent processing and use properties and biodegradability.

[0040] Wherein, the stirring rate in the reactor in step S1 is 100 rpm, the reaction temperature is 500° C., and the reaction time is 5-7 h.

[0041] Wherein, the stirring rate in the mixer in step S2 is 200 rpm, the reaction temperature is 700° C., and the reaction time is 3 h.

[0042] Among them, the screw diameter of the multi-layer co-extrusion extruder is 30mm, the extrusion speed is 50m / min, the screw speed is 600rpm, and it is equipped with 4 temperature zones.

[0043] Embodiment 2:

[0044] A method for preparing a degradable composite woven bag, characterized by comprising the following raw materials in parts by weight:

[0045] 75 parts of degradable plastic, 7 parts of plasticizer, 12 parts of calcium carbonate, 15 parts of silicon dioxide, 5 parts of coupling agent, 3 parts of zinc chloride, 6 parts of antioxidant, 7 parts of light stabilizer, 15 parts of chitosan, 20 parts of toughness additive, 35 parts of starch polyvinyl alcohol, 20 parts of carbon dioxide copolymer, 12 parts of aliphatic aromatic copolyester, 150 parts of kraft paper;

[0046] A method for preparing a degradable composite woven bag based on the above raw materials comprises the following steps:

[0047] S1: Pour 75 parts of biodegradable plastic, 35 parts of starch polyvinyl alcohol, 20 parts of carbon dioxide copolymer and 12 parts of aliphatic aromatic copolyester into a reactor for reaction;

[0048] S2: After the reaction is completed, the above raw materials are taken out and poured into a mixer, and then 7 parts of plasticizer, 12 parts of calcium carbonate, 15 parts of silicon dioxide, 5 parts of coupling agent, 3 parts of zinc chloride, 6 parts of antioxidant, 7 parts of light stabilizer, 15 parts of chitosan and 20 parts of toughness additive are added into the mixer and stirred;

[0049] S3: After the stirring is completed, the above materials are taken out and poured into a multi-layer co-extrusion extruder for film forming;

[0050] S4: Put the film-formed material into a compounding machine and add 150 parts of kraft paper for compounding;

[0051] S5: Use a bag making machine to cut and seal the composite material to make a plastic bag;

[0052] S6: Pack the prepared plastic bag.

[0053] Degradable plastics are made by mixing polylactic acid, polycaprolactone and polyhydroxyalkanoates, in which the weight ratio of polylactic acid, polycaprolactone and polyhydroxyalkanoates is 1:1:2. Polylactic acid can gradually degrade at high temperatures and eventually convert into carbon dioxide and water, which is environmentally friendly. Polycaprolactone is also a biodegradable plastic, which degrades slowly but can gradually degrade under high temperatures and the action of microorganisms. Polyhydroxyalkanoates are another type of biodegradable plastic that can degrade under a variety of environmental conditions, including high temperatures and humid environments. The degradable plastics formed by mixing and copolymerizing them not only have good degradation properties, but also have higher strength.

[0054] The toughness additive is prepared by copolymerization of polybutylene succinate and terephthalate, wherein the weight ratio of polybutylene succinate to terephthalate is 3: 5. By adding the toughness additive, the toughness of the composite woven bag can be further improved without affecting its degradation performance.

[0055] Among them, starch polyvinyl alcohol is prepared by mixing starch and polyvinyl alcohol, wherein the weight ratio between starch and polyvinyl alcohol is 1:3. Starch polyvinyl alcohol combines the advantages of starch and polyvinyl alcohol, and has good biodegradability and certain physical properties. It can be used to improve the barrier properties of plastic bags and reduce costs.

[0056] The carbon dioxide copolymer is formed by the polymerization of carbon dioxide, propylene oxide and succinic anhydride through catalytic reaction, wherein the weight ratio of carbon dioxide, propylene oxide and ethylene oxide is 1:25:25. The carbon dioxide copolymer formed by the polymerization of carbon dioxide, propylene oxide and succinic anhydride through catalytic reaction not only has good degradation and barrier properties, but also has the advantages of transparency and non-toxicity.

[0057] Among them, the aliphatic aromatic copolyester includes adipic acid, sebacic acid and polybutylene terephthalate through catalytic polymerization, wherein the weight ratio of adipic acid, sebacic acid and polybutylene terephthalate is 4:3:2. The aliphatic aromatic copolyester formed by the catalytic polymerization of adipic acid, sebacic acid and polybutylene terephthalate has an excellent structure, and has excellent processing and use properties and biodegradability.

[0058] Wherein, the stirring rate in the reactor in step S1 is 150 rpm, the reaction temperature is 600° C., and the reaction time is 6 h.

[0059] Wherein, the stirring rate in the mixer in step S2 is 250 rpm, the reaction temperature is 800° C., and the reaction time is 4 h.

[0060] Among them, the screw diameter of the multi-layer co-extrusion extruder is 40mm, the extrusion speed is 75m / min, the screw speed is 650rpm, and it is equipped with 4 temperature zones.

[0061] Embodiment 3:

[0062] A method for preparing a degradable composite woven bag, characterized by comprising the following raw materials in parts by weight:

[0063] 100 parts of biodegradable plastic, 10 parts of plasticizer, 15 parts of calcium carbonate, 20 parts of silicon dioxide, 7 parts of coupling agent, 4 parts of zinc chloride, 7 parts of antioxidant, 10 parts of light stabilizer, 20 parts of chitosan, 25 parts of toughness additive, 40 parts of starch polyvinyl alcohol, 25 parts of carbon dioxide copolymer, 15 parts of aliphatic aromatic copolyester, 200 parts of kraft paper;

[0064] A method for preparing a degradable composite woven bag based on the above raw materials comprises the following steps:

[0065] S1: Pour 100 parts of biodegradable plastic, 40 parts of starch polyvinyl alcohol, 25 parts of carbon dioxide copolymer and 15 parts of aliphatic aromatic copolyester into a reactor for reaction;

[0066] S2: After the reaction is completed, the above raw materials are taken out and poured into a mixer, and then 10 parts of plasticizer, 15 parts of calcium carbonate, 20 parts of silicon dioxide, 7 parts of coupling agent, 4 parts of zinc chloride, 7 parts of antioxidant, 10 parts of light stabilizer, 20 parts of chitosan and 25 parts of toughness additive are added into the mixer and stirred;

[0067] S3: After the stirring is completed, the above materials are taken out and poured into a multi-layer co-extrusion extruder for film forming;

[0068] S4: Put the film-formed material into a compounding machine and add 200 parts of kraft paper for compounding;

[0069] S5: Use a bag making machine to cut and seal the composite material to make a plastic bag;

[0070] S6: Pack the prepared plastic bag.

[0071] Degradable plastics are made by mixing polylactic acid, polycaprolactone and polyhydroxyalkanoates, where the weight ratio of polylactic acid, polycaprolactone and polyhydroxyalkanoates is 3:2:5. Polylactic acid can be gradually degraded at high temperatures and eventually converted into carbon dioxide and water, which is environmentally friendly. Polycaprolactone is also a biodegradable plastic, which degrades slowly but can be gradually degraded under high temperatures and microorganisms. Polyhydroxyalkanoates are another type of biodegradable plastic that can be degraded under a variety of environmental conditions, including high temperatures and humid environments. The degradable plastics formed by mixing and copolymerizing them not only have good degradation performance, but also have high strength.

[0072] The toughness additive is prepared by copolymerization of polybutylene succinate and terephthalate, wherein the weight ratio of polybutylene succinate to terephthalate is 4:7. By adding the toughness additive, the toughness of the composite woven bag can be further improved without affecting its degradation performance.

[0073] Among them, starch polyvinyl alcohol is prepared by mixing starch and polyvinyl alcohol, wherein the weight ratio between starch and polyvinyl alcohol is 1:3. Starch polyvinyl alcohol combines the advantages of starch and polyvinyl alcohol, and has good biodegradability and certain physical properties. It can be used to improve the barrier properties of plastic bags and reduce costs.

[0074] The carbon dioxide copolymer is formed by the polymerization of carbon dioxide, propylene oxide and succinic anhydride through catalytic reaction, wherein the weight ratio of carbon dioxide, propylene oxide and ethylene oxide is 1:30:30. The carbon dioxide copolymer formed by the polymerization of carbon dioxide, propylene oxide and succinic anhydride through catalytic reaction not only has good degradation performance and barrier performance, but also has the advantages of transparency and non-toxicity.

[0075] Among them, the aliphatic aromatic copolyester includes adipic acid, sebacic acid and polybutylene terephthalate through catalytic polymerization, wherein the weight ratio of adipic acid, sebacic acid and polybutylene terephthalate is 5:4:3. The aliphatic aromatic copolyester formed by the catalytic polymerization of adipic acid, sebacic acid and polybutylene terephthalate has an excellent structure, and has excellent processing and use properties and biodegradability.

[0076] Wherein, the stirring rate in the reactor in step S1 is 200 rpm, the reaction temperature is 700° C., and the reaction time is 7 h.

[0077] Wherein, the stirring rate in the mixer in step S2 is 300 rpm, the reaction temperature is 900° C., and the reaction time is 5 h.

[0078] Among them, the screw diameter of the multi-layer co-extrusion extruder is 50mm, the extrusion speed is 100m / min, the screw speed is 700rpm, and it is equipped with 4 temperature zones.

[0079] In this embodiment, polylactic acid can be gradually degraded at high temperature and finally converted into carbon dioxide and water, which is environmentally friendly. Polycaprolactone is also a biodegradable plastic, which has a slow degradation rate, but can be gradually degraded under the action of high temperature and microorganisms. Polyhydroxyalkanoate is another biodegradable plastic, which can be degraded under a variety of environmental conditions, including high temperature and humid environment. The degradable plastic formed by mixing and copolymerizing them not only has good degradation performance, but also has high strength.

[0080] Furthermore, by adding toughness additives, the toughness of the composite woven bag can be further improved without affecting its degradation performance.

[0081] Furthermore, starch polyvinyl alcohol combines the advantages of starch and polyvinyl alcohol, has good biodegradability and certain physical properties, and can be used to improve the barrier properties of plastic bags and reduce costs.

[0082] Furthermore, the carbon dioxide copolymer formed by the polymerization of carbon dioxide, propylene oxide and succinic anhydride through a catalytic reaction not only has good degradation and barrier properties, but also has the advantages of being transparent and non-toxic.

[0083] Furthermore, the aliphatic aromatic copolyester formed by polymerization of adipic acid, sebacic acid and polybutylene terephthalate via catalytic reaction has an excellent structure and has excellent processing and use properties and biodegradability.

[0084] By adding degradable plastics, toughening additives, starch polyvinyl alcohol, carbon dioxide copolymers and aliphatic aromatic copolyesters, not only can the various properties of the composite plastic bag be improved, but also its normal degradation performance will not be affected, which is more environmentally friendly and reduces the impact of the composite plastic bag on the environment.

[0085] The composite woven bags prepared in the above embodiment were selected for strength testing, and the test environment, time and other conditions were the same (where A, B, and C are the composite woven bags prepared in this embodiment, and D is a composite woven bag purchased on the market).

[0086]

[0087] In the present invention, by adding degradable plastics, toughness additives, starch polyvinyl alcohol, carbon dioxide copolymers and aliphatic aromatic copolyesters, not only can the various properties of the composite plastic bag be improved, but also its normal degradation performance will not be affected, which is more environmentally friendly and reduces the impact of the composite plastic bag on the environment.

[0088] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a degradable composite woven bag, characterized in that: Including the following raw materials by mass: 50-100 parts of degradable plastic, 5-10 parts of plasticizer, 10-15 parts of calcium carbonate, 10-20 parts of silicon dioxide, 3-7 parts of coupling agent, 2-4 parts of zinc chloride, 5-7 parts of antioxidant, 5-10 parts of light stabilizer, 10-20 parts of chitosan, 15-25 parts of toughness additive, 30-40 parts of starch polyvinyl alcohol, 15-25 parts of carbon dioxide copolymer, 10-15 parts of aliphatic aromatic copolyester, 100-200 parts of kraft paper; A method for preparing a degradable composite woven bag based on the above raw materials comprises the following steps: S1: Pour 50-100 parts of biodegradable plastic, 30-40 parts of starch polyvinyl alcohol, 15-25 parts of carbon dioxide copolymer and 10-15 parts of aliphatic aromatic copolyester into a reactor for reaction; S2: After the reaction is completed, the above raw materials are taken out and poured into a mixer, and then 5-10 parts of plasticizer, 10-15 parts of calcium carbonate, 10-20 parts of silicon dioxide, 3-7 parts of coupling agent, 2-4 parts of zinc chloride, 5-7 parts of antioxidant, 5-10 parts of light stabilizer, 10-20 parts of chitosan and 15-25 parts of toughness additive are added into the mixer and stirred; S3: After the stirring is completed, the above materials are taken out and poured into a multi-layer co-extrusion extruder for film forming; S4: Put the film-formed material into a compounding machine and add 100-200 parts of kraft paper for compounding; S5: Use a bag making machine to cut and seal the composite material to make a plastic bag; S6: Pack the prepared plastic bag.

2. The method for preparing a degradable composite woven bag according to claim 1, characterized in that: The degradable plastic is prepared by mixing polylactic acid, polycaprolactone and polyhydroxyalkanoate, wherein the weight ratio of polylactic acid, polycaprolactone and polyhydroxyalkanoate is (1-3):2:(3-5).

3. The method for preparing a degradable composite woven bag according to claim 1, characterized in that: The toughness additive is prepared by copolymerizing polybutylene succinate and terephthalate, wherein the weight ratio of polybutylene succinate to terephthalate is (2-4): (5-7).

4. The method for preparing a degradable composite woven bag according to claim 1, characterized in that: The starch polyvinyl alcohol is prepared by mixing starch and polyvinyl alcohol, wherein the weight ratio between the starch and the polyvinyl alcohol is 1:

3.

5. The method for preparing a degradable composite woven bag according to claim 1, characterized in that: The carbon dioxide copolymer is formed by polymerization of carbon dioxide, propylene oxide and succinic anhydride through catalytic reaction, wherein the weight ratio of carbon dioxide, propylene oxide and ethylene oxide is 1:(20-30):(20-30).

6. The method for preparing a degradable composite woven bag according to claim 1, characterized in that: The aliphatic aromatic copolyester is formed by polymerization of adipic acid, sebacic acid and polybutylene terephthalate through a catalytic reaction, wherein the weight ratio of adipic acid, sebacic acid and polybutylene terephthalate is (3-5): (2-4): (1-3).

7. The method for preparing a degradable composite woven bag according to claim 1, characterized in that: The stirring rate in the reactor in step S1 is 100-200 rpm, the reaction temperature is 500-700° C., and the reaction time is 5-7 h.

8. The method for preparing a degradable composite woven bag according to claim 1, characterized in that: The stirring rate in the mixer in step S2 is 200-300 rpm, the reaction temperature is 700-900° C., and the reaction time is 3-5 h.

9. The method for preparing a degradable composite woven bag according to claim 1, characterized in that: The multi-layer co-extrusion extruder has a screw diameter of 30-50 mm, an extrusion speed of 50-100 m / min, a screw speed of 600-700 rpm, and is provided with 4 temperature zones.

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