Preparation process of degradable environment-friendly shoe material

Abstract

The invention discloses a preparation process of a degradable environment-friendly shoe material. The preparation process comprises the following steps: step 1, preparing raw materials; step 2, fiber pretreatment; step 3, starch pretreatment; step 4, mixing; step 5, extruding and granulating; step 6, compression molding; the preparation method has the advantages that the degradable material is adopted for preparing the shoe material, the shoe material can be rapidly decomposed in the natural environment, pollution caused by traditional non-degradable shoe materials to soil, water sources and the like is effectively reduced, the positive effect on ecological environment protection is achieved, sustainable development is promoted, and the shoe material has excellent air permeability and comfort; the steps of material pretreatment, mixing and the like are optimized, full combination of all components is ensured, the quality stability of the shoe material is improved, the shoe material has huge market potential, the requirements of different consumer groups can be met, the industry is led to stride towards the environment-friendly sustainable direction, and the shoe material is worthy of popularization and application. And the technical progress, transformation and upgrading of the whole industry are promoted.

Description

Technical Field

[0001] The invention relates to the technical field of shoe material preparation, and in particular to a preparation process of a degradable and environment-friendly shoe material. Background Art

[0002] As global environmental problems become increasingly severe and people's environmental awareness continues to increase, the demand for environmentally friendly products has become increasingly strong. In the field of footwear, traditional shoe materials are usually made of non-degradable synthetic materials, such as plastics, rubber, etc. These materials are difficult to degrade in the natural environment, and long-term accumulation will cause serious pollution to soil, water sources, etc., and also waste a lot of resources.

[0003] At present, although some environmentally friendly shoe materials have appeared, there are still many shortcomings in terms of performance, cost and degradability. On the one hand, although some so-called environmentally friendly shoe materials claim to be degradable, the actual degradation speed is slow, and it is difficult to completely decompose within a reasonable time, and the effect of improving the environment is limited. On the other hand, the preparation process of some environmentally friendly shoe materials is complicated and the cost is high, making it difficult to promote and apply them on a large scale.

[0004] In addition, traditional non-degradable shoe materials have certain advantages in comfort, breathability, wear resistance, etc., but environmentally friendly shoe materials are often difficult to match with them in these properties. Therefore, the development of an environmentally friendly shoe material preparation process that has good degradable properties and can meet people's requirements for shoe material quality and performance has become an urgent problem to be solved in the current footwear industry. In order to reduce the pollution of footwear products to the environment and meet people's demand for environmentally friendly and high-performance shoe materials, it is necessary to develop a preparation process for degradable and environmentally friendly shoe materials. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a preparation process of a degradable and environmentally friendly shoe material which is simple in design, reliable in use, easy to clean, strong in damage resistance and low in cost.

[0006] In order to solve the above technical problems, the present invention is solved by the following technical solutions: A preparation process of a degradable and environmentally friendly shoe material comprises the following steps:

[0007] Step 1, raw material preparation: 30-40 parts of natural fiber material, 40-50 parts of biodegradable polymer, 10-15 parts of plant starch, 5-8 parts of environmentally friendly plasticizer citric acid ester, 2-4 parts of coupling agent silane coupling agent and 1-2 parts of antioxidant natural vitamin E;

[0008] Step 2, fiber pretreatment: wash the natural fiber material to remove impurities and dust, dry the washed fiber material in an oven at 60-80°C for 4-6 hours to reduce its moisture content to below 5%, and crush the dried fiber material to a length within the range of 1-3 mm;

[0009] Step 3, starch pretreatment: Dry the plant starch at a temperature of 80-100°C for 3-5 hours to ensure that the moisture content of the starch is less than 3%, and grind the dried starch to make its particle size uniform, with a particle size between 50-100 microns;

[0010] Step 4, mixing: adding the biodegradable polymer into a high-speed mixer, preheating at a temperature of 70-90° C. for 5-10 minutes, sequentially adding the pretreated natural fiber material, plant starch, environmentally friendly plasticizer, coupling agent and antioxidant, mixing at a temperature of 90-110° C. at a speed of 1000-1500 revolutions per minute for 15-25 minutes to obtain a uniform mixed material;

[0011] Step 5, extrusion granulation: add the mixed material into a twin-screw extruder, set the temperature of each section of the extruder to: zone 1 120-130°C, zone 2 130-140°C, zone 3 140-150°C, zone 4 150-160°C, and die head temperature 155-165°C, extrude into strips through the extruder, and then cool and pelletize to obtain degradable particles;

[0012] Step 6, compression molding: adding the degradable particles into a shoe material mold, preheating the mold to 160-180°C, performing compression molding at a pressure of 10-15 MPa, holding the pressure for 10-15 minutes, cooling and demoulding, and obtaining a degradable and environmentally friendly shoe material;

[0013] Step 7, post-processing: trim and polish the formed shoe material to remove burrs and excess parts, spray an environmentally friendly waterproof agent on the surface of the shoe material to enhance the waterproof performance of the shoe material, and place the shoe material in a well-ventilated environment for 24-48 hours to stabilize its performance.

[0014] Preferably, the raw materials include natural fiber materials, biodegradable polymers, plant starch, environmentally friendly plasticizers, coupling agents and antioxidants. The natural fiber materials include flax fibers, bamboo fibers, etc., and the biodegradable polymers include polylactic acid, polycaprolactone, etc.

[0015] Preferably, the natural fiber material is one or both of flax fiber and bamboo fiber, with a weight ratio of 30-40 parts, and the biodegradable polymer is one or both of polylactic acid and polycaprolactone, with a weight ratio of 40-50 parts.

[0016] Preferably, the weight portion of the plant starch is 10-15 parts, and the weight portion of the environmentally friendly plasticizer is citric acid ester, which is 5-8 parts.

[0017] Preferably, the coupling agent is a silane coupling agent, and its weight portion is 2-4 parts; the antioxidant is natural vitamin E, and its weight portion is 1-2 parts.

[0018] Preferably, after the natural fiber material is washed, it is dried in an oven at 60-80°C for 4-6 hours, and the length of the crushed fiber material is 1-3 mm. The plant starch is dried at 80-100°C for 3-5 hours, and the starch granules after grinding have a particle size of 50-100 μm.

[0019] Preferably, the high-speed mixing temperature is 90-110° C., the speed is 1000-1500 rpm, and the mixing time is 15 to 25 minutes. After the biodegradable polymer is preheated, the treated natural fiber material, plant starch, environmentally friendly plasticizer, coupling agent and antioxidant are added in sequence and mixed at a specific temperature at a high speed.

[0020] Preferably, the cooling treatment is to naturally cool the hot-pressed shoe material to room temperature, and the mixed material is to evenly mix the pretreated natural fiber, starch-based polymer and biodegradable resin with an appropriate amount of plasticizer and coupling agent at a specific temperature and stirring speed, the mixing temperature is 80-100°C, and the stirring speed is 500-800 rpm.

[0021] Preferably, the mixing step is carried out in a high-speed mixer, the mixing temperature is 80°C-100°C, the mixing time is 15 minutes-30 minutes, the compression molding temperature is 150°C-180°C, the pressure is 5MPa-10MPa, and the holding time is 10 minutes-20 minutes.

[0022] Preferably, the post-processing includes trimming, grinding, spraying of environmentally friendly waterproof agent and placement, and the post-processing includes spraying of environmentally friendly waterproof agent on the surface of the shoe material to enhance the waterproof performance of the shoe material.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. The preparation process of the degradable and environmentally friendly shoe material of the present invention adopts degradable materials to prepare shoe materials, which can be quickly decomposed in the natural environment, effectively reducing the pollution caused by traditional non-degradable shoe materials to soil, water sources, etc., playing a positive role in protecting the ecological environment, reducing the dependence of the shoe material industry on non-renewable resources such as petroleum, promoting sustainable development, and having high environmental protection;

[0025] 2. The preparation process of the degradable and environmentally friendly shoe material of the present invention, through a carefully designed preparation process, makes the shoe material perform well in mechanical properties, with excellent strength, toughness and wear resistance, which can meet the needs of daily wear and use, and has excellent air permeability and comfort, so that the user's feet can be kept dry and the wearing experience is improved;

[0026] 3. The preparation process of the degradable and environmentally friendly shoe material of the present invention is unique and simple, easy to implement industrial production, can effectively reduce production costs, improve production efficiency, optimize the steps of material pretreatment and mixing, ensure that all components are fully combined, and improve the quality stability of the shoe material;

[0027] 4. The preparation process of the degradable and environmentally friendly shoe material of the present invention has huge market potential, can meet the needs of different consumer groups, provides a new development direction for the shoe material industry, leads the industry to move towards environmental protection and sustainability, and promotes technological progress and transformation and upgrading of the entire industry. DETAILED DESCRIPTION

[0028] Unless the context clearly dictates otherwise, unmodified nouns and nouns modified by "the" include singular and plural referents.

[0029] As used in the specification and claims, the terms "comprises," "comprising," "having," "may," "containing," and variations thereof as used herein refer to open transitional phrases, terms, or words that require the presence of specified ingredients / steps and allow for the presence of other ingredients / steps. However, such descriptions should be interpreted as also describing compositions or methods as "consisting of" and "consisting essentially of" the recited ingredients / steps, which allows for the presence of only the specified ingredients / steps and any unavoidable impurities that may result therefrom, and excludes other ingredients / steps.

[0030] Numerical values ​​in the specification and claims of this application should be understood to include the same numerical values ​​when reduced to the same number of significant figures and numerical values ​​that differ from the stated value by less than the experimental error of ordinary measurement techniques of the type described in this application for determining the stated value.

[0031] All ranges disclosed herein are inclusive of the indicated endpoints and are independently combinable (eg, the range of "2 grams to 10 grams" includes the endpoints 2 grams and 10 grams, and all intermediate values).

[0032] The terms "about" and "approximately" can be used to include any numerical value that can be varied without changing the basic function of the value. When used with a range, "about" and "approximately" also disclose the range defined by the absolute values ​​of the two endpoints, for example, "about 2 to about 4" also discloses a range of "2 to 4". Generally, the terms "about" and "approximately" can refer to ±10% of the indicated number. However, for temperature, the term "approximately" refers to ±1°C.

[0033] Unless expressly stated otherwise, the percentages of elements are to be considered as percentages by weight of the alloy in question.

[0034] The present disclosure may refer to the temperature of certain method steps. It should be noted that these specifications generally refer to the temperature set by the heat source (such as a furnace), and not necessarily the temperature that the heated material must reach.

[0035] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be used for other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0036] Embodiment 1: A process for preparing a degradable and environmentally friendly shoe material, comprising the following steps:

[0037] Step 1: Raw material preparation:

[0038] Select 30 parts of natural fiber (such as hemp fiber), 40 parts of starch-based polymer, 30 parts of biodegradable resin, 5 parts of plasticizer (tributyl citrate), and 3 parts of coupling agent (silane coupling agent).

[0039] Step 2: Material pretreatment:

[0040] The hemp fibers were cleaned to remove impurities, dried in an oven at 60°C for 4 hours, and then pulverized to a fiber length of about 2 mm.

[0041] Step 3: Mixing:

[0042] The starch-based polymer and the biodegradable resin were added into a high-speed mixer, preheated at 80°C for 5 minutes, and the pretreated hemp fiber, the plasticizer and the coupling agent were added in sequence, and mixed at 90°C at a speed of 600 rpm for 20 minutes to obtain a uniform mixture.

[0043] Step 4: Hot Pressing:

[0044] The mixed material was placed into a shoe material mold and hot-pressed at 160°C and 12 MPa for 15 minutes.

[0045] Step 5: Cooling treatment:

[0046] The shoe material after hot pressing is naturally cooled to room temperature.

[0047] Step 6: Surface treatment:

[0048] Spray environmentally friendly waterproof agent on the surface of shoe materials to enhance the waterproof performance of the shoe materials.

[0049] Embodiment 2: A process for preparing a degradable and environmentally friendly shoe material, comprising the following steps:

[0050] Step 1: Raw material preparation:

[0051] 35 parts of natural fiber (bamboo fiber), 35 parts of starch-based polymer, 30 parts of biodegradable resin, 6 parts of plasticizer (acetyl tributyl citrate), and 2 parts of coupling agent (titanate coupling agent).

[0052] Step 2: Material pretreatment:

[0053] After cleaning, the bamboo fibers were dried in an oven at 70°C for 3 h and crushed to a fiber length of 1.5 mm.

[0054] Step 3: Mixing:

[0055] The starch-based polymer and biodegradable resin were preheated at 90°C for 8 minutes, and the pretreated bamboo fiber, plasticizer and coupling agent were added and mixed at 95°C at a speed of 700 rpm for 18 minutes.

[0056] Step 4: Hot Pressing:

[0057] The mixed material was placed in the mold and hot pressed at 170°C and 10 MPa, with the pressure maintained for 12 minutes.

[0058] Step 5: Cooling treatment:

[0059] Cool naturally to room temperature.

[0060] Step 6: Surface treatment:

[0061] Spray environmentally friendly waterproofing agent.

[0062] Embodiment 3: A process for preparing a degradable and environmentally friendly shoe material, comprising the following steps:

[0063] Step 1: Raw material preparation:

[0064] 28 parts of natural fiber (mixed with cotton fiber and hemp fiber in a ratio of 1:1), 42 parts of starch-based polymer, 30 parts of biodegradable resin, 4 parts of plasticizer (epoxidized soybean oil), and 3 parts of coupling agent (silane coupling agent).

[0065] Step 2: Material pretreatment:

[0066] The mixed fibers were washed, dried in an oven at 55°C for 5 hours, and pulverized to a fiber length of 2.5 mm.

[0067] Step 3: Mixing:

[0068] The starch-based polymer and the biodegradable resin were preheated at 85°C for 6 minutes, and the pretreated mixed fibers, plasticizer and coupling agent were added and mixed at 88°C at a speed of 550 rpm for 22 minutes.

[0069] Step 4: Hot Pressing:

[0070] The material was placed in the mold and hot pressed at 155°C and 13MPa, with the pressure maintained for 14 minutes.

[0071] Step 5: Cooling treatment:

[0072] Cool naturally to room temperature.

[0073] Step 6: Surface treatment:

[0074] Spray environmentally friendly waterproofing agent.

[0075] Example 4: Preparation process of a degradable and environmentally friendly shoe material

[0076] 1. Weigh 30 parts of natural rubber, 15 parts of starch, 10 parts of cellulose, 5 parts of plasticizer, 2 parts of coupling agent and 1 part of antioxidant.

[0077] 2. Dry the starch to make its moisture content less than 5%.

[0078] 3. Add natural rubber, pretreated starch, cellulose, plasticizer, coupling agent and antioxidant into a high-speed mixer, mix at 80° C. for 20 minutes to obtain a mixed material.

[0079] 4. Add the mixture into an internal mixer and mix at 120°C for 25 minutes.

[0080] 5. Add the mixed material into an open mixer and mix at 80°C for 15 minutes to obtain a rubber compound.

[0081] 6. Add the rubber into the shoe material forming machine and form it at a temperature of 150°C to obtain a degradable and environmentally friendly shoe material.

[0082] Example 5: Preparation process of a degradable and environmentally friendly shoe material

[0083] 1. Weigh 40 parts of natural rubber, 25 parts of starch, 20 parts of cellulose, 10 parts of plasticizer, 5 parts of coupling agent, and 3 parts of antioxidant.

[0084] 2. Dry the starch to make its moisture content less than 5%.

[0085] 3. Add natural rubber, pretreated starch, cellulose, plasticizer, coupling agent and antioxidant into a high-speed mixer, mix at 100° C. for 10 minutes to obtain a mixed material.

[0086] 4. Add the mixture into an internal mixer and mix at 140°C for 15 minutes.

[0087] 5. Add the mixed material into an open mixer and mix at 100°C for 10 minutes to obtain a rubber compound.

[0088] 6. Add the rubber into a shoe material forming machine and form it at a temperature of 170°C to obtain a degradable and environmentally friendly shoe material.

[0089] Comparative Example: The traditional shoe material preparation process was adopted to prepare the shoe material with synthetic rubber as the main raw material.

[0090] The shoe materials prepared in Example 4, Example 5 and the comparative example were subjected to performance tests, and the results are shown in the following table:

[0091] sheet

[0092]

[0093]

[0094] From the above test results, it can be seen that the degradable and environmentally friendly shoe material of the present invention has slightly lower mechanical properties such as tensile strength, elongation at break and tear strength than traditional shoe materials, but can still meet the use requirements of shoe materials. At the same time, the degradation time of the degradable and environmentally friendly shoe material of the present invention in the natural environment is significantly shortened, and has good environmental performance.

[0095] The specific steps are as follows: the staff first weighs the following raw materials by weight: natural fiber materials, such as flax fiber, bamboo fiber, etc. 30-40 parts, biodegradable polymers, such as polylactic acid, polycaprolactone, etc. 40-50 parts, plant starch 10-15 parts, environmentally friendly plasticizers, such as citrate esters 5-8 parts, coupling agents, such as silane coupling agents 2-4 parts, antioxidants, such as natural vitamin E1-2 parts, then the staff washes the natural fiber materials to remove impurities and dust, and dry the washed fiber materials in an oven at 60-80°C for 4-6 hours , so that its moisture content drops below 5%. The staff then crushes the dried fiber material to make its length within the range of 1-3 mm. At this time, the staff dries the plant starch at a temperature of 80-100°C for 3-5 hours to ensure that the starch moisture content is less than 3%, and grinds the dried starch to make its particle size uniform, with a particle size between 50-100 microns. At this time, the staff adds the biodegradable polymer into the high-speed mixer, preheats it at a temperature of 70-90°C for 5-10 minutes, and adds the pretreated natural fiber material, plant Starch, environmentally friendly plasticizer, coupling agent and antioxidant are mixed at a temperature of 90-110°C and a speed of 1000-1500 rpm for 15-25 minutes to obtain a uniform mixture. At this time, the staff adds the mixture into a twin-screw extruder. The temperature of each section of the extruder is set to: zone 1 120-130°C, zone 2 130-140°C, zone 3 140-150°C, zone 4 150-160°C, and the head temperature is 155-165°C. The material is extruded into strips through the extruder, and then cooled and pelletized to obtain degradable particles. The staff then adds the degradable particles into the shoe material mold, preheats the mold to 160-180℃, and performs compression molding at a pressure of 10-15MPa for 10-15 minutes. Finally, the mold is cooled and demolded to obtain degradable and environmentally friendly shoe materials. At this time, the staff trims and polishes the molded shoe materials to remove burrs and excess parts, and sprays environmentally friendly waterproofing agent on the surface of the shoe materials to enhance the waterproof performance of the shoe materials. Finally, the shoe materials are placed in a well-ventilated environment for 24-48 hours to stabilize their performance, and finally the preparation process of degradable and environmentally friendly shoe materials is completed.

[0096] It should be understood by those skilled in the art that the embodiments of the present invention shown in the above description are only examples and do not limit the present invention. The purpose of the present invention has been fully and effectively achieved. The functions and structural principles of the present invention have been demonstrated and explained in the embodiments. Without departing from the principles, the embodiments of the present invention may have any changes or modifications. Although the embodiments of the present invention have been shown and described, it is understood by those of ordinary skill in the art that various changes, modifications, substitutions and deformations may be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the attached claims and their equivalents. This specific embodiment is only an explanation of the present application, and it is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without creative contribution as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A process for preparing a degradable and environmentally friendly shoe material, characterized in that: The following steps are involved: Step 1, raw material preparation: 30-40 parts of natural fiber material, 40-50 parts of biodegradable polymer, 10-15 parts of plant starch, 5-8 parts of environmentally friendly plasticizer citric acid ester, 2-4 parts of coupling agent silane coupling agent and 1-2 parts of antioxidant natural vitamin E; Step 2, fiber pretreatment: wash the natural fiber material to remove impurities and dust, dry the washed fiber material in an oven at 60-80°C for 4-6 hours to reduce its moisture content to below 5%, and crush the dried fiber material to a length within the range of 1-3 mm; Step 3, starch pretreatment: Dry the plant starch at a temperature of 80-100°C for 3-5 hours to ensure that the moisture content of the starch is less than 3%, and grind the dried starch to make its particle size uniform, with a particle size between 50-100 microns; Step 4, mixing: adding the biodegradable polymer into a high-speed mixer, preheating at a temperature of 70-90° C. for 5-10 minutes, sequentially adding the pretreated natural fiber material, plant starch, environmentally friendly plasticizer, coupling agent and antioxidant, mixing at a temperature of 90-110° C. at a speed of 1000-1500 revolutions per minute for 15-25 minutes to obtain a uniform mixed material; Step 5, extrusion granulation: add the mixed material into a twin-screw extruder, set the temperature of each section of the extruder to: zone 1 120-130°C, zone 2 130-140°C, zone 3 140-150°C, zone 4 150-160°C, and die head temperature 155-165°C, extrude into strips through the extruder, and then cool and pelletize to obtain degradable particles; Step 6, compression molding: adding the degradable particles into a shoe material mold, preheating the mold to 160-180°C, performing compression molding at a pressure of 10-15 MPa, holding the pressure for 10-15 minutes, cooling and demoulding, and obtaining a degradable and environmentally friendly shoe material; Step 7, post-processing: trim and polish the formed shoe material to remove burrs and excess parts, spray an environmentally friendly waterproof agent on the surface of the shoe material to enhance the waterproof performance of the shoe material, and place the shoe material in a well-ventilated environment for 24-48 hours to stabilize its performance.

2. The process for preparing a degradable and environmentally friendly shoe material according to claim 1, characterized in that: The raw materials include natural fiber materials, biodegradable polymers, plant starch, environmentally friendly plasticizers, coupling agents and antioxidants. The natural fiber materials include flax fibers, bamboo fibers, etc., and the biodegradable polymers include polylactic acid, polycaprolactone, etc.

3. The process for preparing a degradable and environmentally friendly shoe material according to claim 1, characterized in that: The natural fiber material is one or two of flax fiber and bamboo fiber, and the weight parts thereof are 30-40 parts; the biodegradable polymer is one or two of polylactic acid and polycaprolactone, and the weight parts thereof are 40-50 parts.

4. The process for preparing a degradable and environmentally friendly shoe material according to claim 1, characterized in that: The weight portion of the plant starch is 10-15 parts, and the weight portion of the environmentally friendly plasticizer is citric acid esters, which is 5-8 parts.

5. The process for preparing a degradable and environmentally friendly shoe material according to claim 1, characterized in that: The coupling agent is a silane coupling agent, and its weight portion is 2-4 parts; the antioxidant is natural vitamin E, and its weight portion is 1-2 parts.

6. The process for preparing a degradable and environmentally friendly shoe material according to claim 1, characterized in that: After the natural fiber material is washed, it is dried in an oven at 60-80°C for 4-6 hours. The length of the crushed fiber material is 1-3 mm. The plant starch is dried at 80-100°C for 3-5 hours. The starch granules after grinding have a particle size of 50-100 μm.

7. The process for preparing a degradable and environmentally friendly shoe material according to claim 1, characterized in that: The high-speed mixing temperature is 90-110° C., the speed is 1000-1500 rpm, and the mixing time is 15-25 minutes. After the biodegradable polymer is preheated, the treated natural fiber material, plant starch, environmentally friendly plasticizer, coupling agent and antioxidant are added in sequence and mixed at a specific temperature at a high speed.

8. The process for preparing a degradable and environmentally friendly shoe material according to claim 1, characterized in that: The cooling treatment is to naturally cool the hot-pressed shoe material to room temperature. The mixed material is to evenly mix the pretreated natural fiber, starch-based polymer and biodegradable resin with an appropriate amount of plasticizer and coupling agent at a specific temperature and stirring speed. The mixing temperature is 80-100°C and the stirring speed is 500-800 rpm.

9. The process for preparing a degradable and environmentally friendly shoe material according to claim 1, characterized in that: The mixing step is carried out in a high-speed mixer at a mixing temperature of 80°C-100°C and a mixing time of 15 minutes-30 minutes. The compression molding temperature is 150°C-180°C, the pressure is 5MPa-10MPa, and the holding time is 10 minutes-20 minutes.

10. The process for preparing a degradable and environmentally friendly shoe material according to claim 1, characterized in that: The post-processing includes trimming, grinding, spraying environmentally friendly waterproofing agent and placement. The post-processing includes spraying environmentally friendly waterproofing agent on the surface of the shoe material to enhance the waterproof performance of the shoe material.

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