A method for preparing bio-based plastic film products using kitchen waste

Abstract

The present application provides a method for preparing bio-based plastic film products using kitchen waste. The preparation method comprises the following steps: crushing, dehydrating and grinding the kitchen waste to prepare an organic mixture; mixing the organic mixture with starch, corrosion inhibitor and toughening agent for extrusion granulation to prepare organic solid particles; and using the organic solid particles to make films to prepare the bio-based plastic film products. The present application uses kitchen waste, which is abundant in source and low in cost, as raw material to make it into recyclable bio-based plastic film products, which can effectively alleviate the problem of environmental pollution caused by traditional plastic products, and at the same time realize the resource recycling of kitchen waste.

Description

Technical Field

[0001] The present application relates to the technical field of plastic products, and in particular to a method for preparing bio-based plastic film products using kitchen waste. Background Art

[0002] After the Belgian scientist Pax Schuschny invented plastic in 1902, plastic products have been widely used in people's production and life. While plastic products make people's lives more convenient, they have also caused catastrophic damage to the ecological environment. Plastic products are usually made of polyethylene (PE) and polyvinyl chloride (PVC). Under natural conditions, they cannot be completely degraded in 100 to 200 years. These "white pollutants" have caused serious damage to the ecological environment. Therefore, the call for "banning plastic" is getting louder and louder.

[0003] At present, in order to reduce the pollution of plastics to the ecological environment, scientists are exploring the following directions: breaking through plastic degradation technology and developing biodegradable bio-based plastics. Breakthroughs in plastic degradation technology mainly include the following four directions: (1) Using microorganisms and enzymes to decompose plastics; by adding biodegradable agents during the plastic manufacturing process, plastics are more easily decomposed by microorganisms in the natural environment. Common biodegradable additives include polylactic acid (PLA) and polyhydroxyalkanoates (PHA). (2) Photocatalytic degradation: using light and catalysts to accelerate the degradation of plastics. This method uses specific catalysts and light sources to trigger chemical reactions to degrade plastics; however, this method is only applicable to some specific plastics, such as polyethylene (PE) and polypropylene (PP). (3) Thermal degradation: by treating plastics at high temperatures, the molecular chains are broken and decomposed into low molecular weight compounds. This method is usually carried out under high temperature and pressure conditions to accelerate the degradation of plastics. Thermal degradation can be used for a variety of plastic types, but it is easy to cause air pollution. (4) Chemical degradation: using chemical reactions to decompose plastics into smaller compounds, including using solvents, acids, alkalis and other chemicals to treat plastics to decompose and degrade them; this method is prone to secondary pollution of the environment and has high subsequent treatment costs. In addition, the development of degradable bio-based plastics usually uses starch as raw material to produce bio-based plastic bags; however, the starch-based plastic products produced by this method are prone to aging and becoming brittle, have poor mechanical properties and water resistance, are costly, require a large amount of food, affect food security, and are not suitable for large-scale promotion and application.

[0004] Therefore, the traditional technology still needs to be improved. Summary of the invention

[0005] Based on this, the present application provides a method for preparing bio-based plastic film products using kitchen waste. The technical solution includes:

[0006] According to a first aspect of an embodiment of the present application, a method for preparing a bio-based plastic film product is provided, comprising the following steps:

[0007] The kitchen waste is crushed, dehydrated and ground to prepare an organic matter mixture;

[0008] Mixing the organic mixture with starch, corrosion inhibitor and toughening agent and performing extrusion granulation to prepare organic solid particles; and

[0009] The organic solid particles are used to make films to prepare the bio-based plastic film products.

[0010] In one embodiment, the organic mixture includes 70wt% to 80wt% of plant crude fiber and 20wt% to 30wt% of starch, calculated by mass percentage.

[0011] In one embodiment, the step of preparing the organic mixture comprises:

[0012] Crush the kitchen waste to obtain crushed waste;

[0013] Performing solid-liquid separation on the crushed garbage to obtain semi-wet garbage;

[0014] Squeezing the semi-wet garbage to obtain granular garbage; and

[0015] The granular garbage is homogenized and ground to obtain an organic matter mixture.

[0016] In one embodiment, the preparation method satisfies at least one of the following conditions (1) to (3):

[0017] (1) The water content of the semi-wet garbage is 40wt%~50wt%;

[0018] (2) the water content of the granular waste is 3 wt% to 5 wt%; and

[0019] (3) The water content of the organic mixture is 0.3wt%~0.5wt%.

[0020] In one embodiment, the preparation method satisfies at least one of the following conditions (1) to (3):

[0021] (1) The average particle size of the crushed garbage is 3.1 mm to 5 mm;

[0022] (2) the average particle size of the granular waste is 1 mm to 3 mm; and

[0023] (3) The particle size of the organic mixture is 400 mesh to 600 mesh.

[0024] In one embodiment, extrusion granulation comprises the following steps:

[0025] Detecting the mass percentage of starch in the organic matter mixture;

[0026] Adding starch, a corrosion inhibitor and a toughening agent to the organic mixture so that the total mass percentage of starch in the organic mixture is 60wt% to 65wt%;

[0027] The organic mixture is mixed with starch, a corrosion inhibitor and a toughening agent to obtain a premix; and the premix is ​​extruded and granulated.

[0028] In one embodiment, the toughening agent includes one or more of polylactic acid and polyhydroxyalkanoic acid ester.

[0029] In one embodiment, the temperature of the extrusion granulation is 58°C to 62°C.

[0030] In one embodiment, the process of preparing a membrane using the organic solid particles comprises the following steps:

[0031] Melting the organic solid particles and then performing film blowing or film drawing;

[0032] Wherein, the temperature of the film blowing is 60℃~80℃; the temperature of the film drawing is 60℃~80℃.

[0033] According to a second aspect of an embodiment of the present application, a bio-based plastic film product is provided, which is prepared using the above-mentioned method for preparing a bio-based plastic film product.

[0034] Compared with the traditional technology, this application has the following beneficial effects:

[0035] The present application uses kitchen waste as raw material, and through crushing, dehydration, grinding, granulation and film making, the bio-based plastic film products prepared can be completely degraded under natural conditions and have good mechanical properties and water resistance. The present application uses kitchen waste, which is abundant and low in cost, as raw material to make it into recyclable bio-based plastic film products, which can effectively alleviate the problem of environmental pollution caused by traditional plastic products, and at the same time realize the resource recycling of kitchen waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the specific implementation methods of the present application 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 application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0037] Figure 1 This is a schematic diagram of the preparation process of the bio-based plastic bag in Example 1 of the present application. DETAILED DESCRIPTION

[0038] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present application. The terms used herein in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. Unless otherwise specifically stated, various raw materials, reagents, instruments and equipment used in the present application, etc. can be purchased from the market or can be prepared by existing methods.

[0040] In the present application, "plurality", "multiple", "multiple times", "plurality", etc., unless otherwise specified, refer to a number greater than 2 or equal to 2. For example, "one or more" means one or greater than or equal to two.

[0041] In this application, "optionally", "optional", and "optional" mean optional or dispensable, that is, any one of the two parallel schemes of "yes" or "no". If multiple "options" appear in a technical solution, unless otherwise specified and there is no contradiction or mutual restriction, each "optional" is independent.

[0042] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0043] In the present application, when it comes to numerical intervals (i.e., numerical ranges), unless otherwise specified, the optional numerical distribution is considered continuous within the above numerical interval, and includes the two numerical endpoints (i.e., the minimum and maximum values) of the numerical range, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to the integers within the numerical interval, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints. In this article, it is equivalent to directly listing each integer, such as t is an integer selected from 1-10, indicating that t is any integer selected from the integer group consisting of 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10. In addition, when multiple ranges are provided to describe features or characteristics, these ranges can be combined. In other words, unless otherwise specified, the ranges disclosed herein should be understood to include any and all sub-ranges included therein.

[0044] The temperature parameters in this application, unless otherwise specified, are allowed to be either constant temperature treatment or to vary within a certain temperature range. It should be understood that the constant temperature treatment allows the temperature to fluctuate within the accuracy range controlled by the instrument. Fluctuations within the range of ±5°C, ±4°C, ±3°C, ±2°C, and ±1°C are allowed.

[0045] In the present application, %(w / w) and wt% both represent weight percentage, %(v / v) refers to volume percentage, and %(w / v) refers to mass volume percentage.

[0046] In recent years, strict garbage classification standards and methods for collection, storage, placement and disposal have been formulated. Community property management strictly supervises and kitchen waste is strictly classified and placed in designated kitchen waste collection bins at regular times and locations.

[0047] Based on this, some embodiments of the present application provide a method for preparing a bio-based plastic film product, including steps S10 to S30.

[0048] Step S10: crushing, dehydrating and grinding the kitchen waste to prepare an organic matter mixture.

[0049] Kitchen waste is the leftovers, leftover rice, fruit peels, eggshells, tea dregs, animal offal, Chinese medicine residues, bones (chicken bones, fish bones, etc.), expired and spoiled food, etc. that are discarded by residents after garbage sorting. Its main source is household kitchens. The main components of kitchen waste include starch, organic matter, protein, cellulose and lipids.

[0050] The smallest molecules of starch are monosaccharides and disaccharides, which can be decomposed by microorganisms to make them porous, thereby increasing the specific surface area of ​​bio-based plastic film products, which is conducive to the enzymatic hydrolysis or natural degradation of bio-based plastic film products. Protein is mainly composed of chemical elements such as carbon, hydrogen, oxygen, and nitrogen. It is an important type of biological macromolecule. Protein is easily hydrolyzed into amino acids. Plant cellulose is a filamentous or flocculent substance generated by the combination of cellulose and various nutrients. It has the functions of supporting, connecting, wrapping, and filling plants. Plant fibers have particularly developed bast fiber bundles. The organic combination of bast fiber bundles with starch, protein, etc. can provide good tension and affinity for bio-based plastic film products, and plays a natural role in improving the tension and water resistance of bio-based plastic film products. Cellulose is easily degraded in the natural environment, and finally forms carbon dioxide, water and fiber flocs. Fiber flocs can improve soil and improve soil permeability. Lipids are mainly composed of three elements: carbon, hydrogen, and oxygen, mainly including lipids, sterols, and phospholipids. The content of lipid substances in residents' kitchen waste is not high, and the value of collecting recycled fuel oil is not high. In the process of preparing bio-based plastic film products, it is washed into the sewer and ingested by microorganisms to provide energy for microorganisms. Inorganic salts are composed of sodium ions and chloride ions, with high chemical stability and easy to dissolve in water. A small amount of inorganic salts in kitchen waste are washed with water, and a large amount of inorganic salts are dissolved in water and enter the sewer. It has multiple functions such as buffering, neutralization, and precipitation, and can effectively remove impurities and pollutants in wastewater.

[0051] In some embodiments, step S10 includes steps S11 to S14.

[0052] Step S11: Crush the kitchen waste to obtain crushed waste.

[0053] In some specific embodiments, the average particle size of the crushed garbage is 3.1 mm to 5 mm. Specifically, the average particle size of the crushed garbage can be any specific value between 3.1 mm and 5 mm, including but not limited to 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.7 mm, 3.8 mm, 3.9 mm, 4.0 mm, 4.1 mm, 4.2 mm, 4.3 mm, 4.4 mm, 4.5 mm, 4.6 mm, 4.7 mm, 4.8 mm, 4.9 mm and 5.0 mm.

[0054] It can be understood that crushing kitchen waste into smaller-sized broken garbage reduces the total volume of the garbage to be processed, making it easier to transport and subsequently process; and reduces the subsequent processing time and difficulty of broken garbage, semi-wet garbage and granular garbage, thereby improving the preparation efficiency of bio-based plastic film products.

[0055] Step S12: performing solid-liquid separation on the crushed garbage to obtain semi-wet garbage.

[0056] The first water removal treatment of the crushed garbage is achieved through solid-liquid separation.

[0057] In some specific embodiments, the water content of the semi-wet garbage is 40wt%~50wt%. Understandably, "water content" refers to the ratio of the mass of water contained in the semi-wet garbage to the total mass of the semi-wet garbage. Optionally, the water content of the semi-wet garbage is 40wt%~45wt%; further optionally, the water content of the semi-wet garbage is 45wt%.

[0058] Understandably, by removing water from semi-wet garbage, most of the water and oil in the crushed garbage can be removed. The filtered water and oil are collected in the grease trap of the sewage station and then sent to the sewage treatment station for unified treatment, which can reduce pollution to the environment.

[0059] Step S13: squeezing the semi-wet garbage to obtain granular garbage.

[0060] In some specific embodiments, the average particle size of the granular garbage is 1 mm to 3 mm. Specifically, the average particle size of the crushed garbage can be any specific value between 1 mm and 3 mm, including but not limited to 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm and 3.0 mm.

[0061] In some specific embodiments, the water content of the granular waste is 3wt% to 5wt%. Optionally, the water content of the granular waste is 3wt% to 4wt%; further optionally, the water content of the granular waste is 3wt%.

[0062] In some specific embodiments, the semi-wet garbage is subjected to a second crushing process and a second water removal process by squeezing. It is understandable that the water and oil filtered out in this step are collected in the grease trap of the sewage station and subsequently sent to the sewage treatment station for unified treatment.

[0063] Step S14: homogenizing and grinding the above granular garbage to obtain an organic mixture.

[0064] Specifically, the third water removal treatment and the third crushing treatment of the granular garbage are achieved through homogenization.

[0065] In some specific embodiments, the particle size of the organic mixture is 400-600 mesh; specifically, the particle size of the organic mixture can be any specific value between 400-600 mesh, including but not limited to 400 mesh, 420 mesh, 440 mesh, 460 mesh, 480 mesh, 500 mesh, 520 mesh, 540 mesh, 560 mesh, 580 mesh or 600 mesh. Optionally, the particle size of the organic mixture is 500-600 mesh; further optionally, the particle size of the organic mixture is 600 mesh.

[0066] In some specific embodiments, the organic mixture includes 70wt% to 80wt% plant crude fiber and 20wt% to 30wt% starch by mass percentage. Optionally, the organic mixture also includes a small amount of lipids, proteins, inorganic salts and water, and the sum of the contents of the above substances is 1.5wt% to 2.5wt%; further optionally, the sum of the contents of lipids, proteins, inorganic salts and water is 2wt%.

[0067] In some specific embodiments, the water content in the organic mixture is 0.3 wt% to 0.5 wt%. Optionally, the water content in the organic mixture is 0.3 wt% to 0.4 wt%.

[0068] Step S20: mixing the organic mixture with starch, corrosion inhibitor and toughening agent, and performing extrusion granulation to prepare organic solid particles.

[0069] In some implementations, step S20 includes steps S21 and S22.

[0070] Step S21: Mix the organic mixture with starch, corrosion inhibitor and toughening agent to obtain a premix.

[0071] It is understandable that the corrosion inhibitor and toughening agent may be those commonly used in the art.

[0072] Optionally, the toughening agent includes one or more of polylactic acid (PLA) and polyhydroxyalkanoate (PHA). Specifically, the performance requirements of bio-based plastic film products in different application scenarios can be met by changing the type and amount of corrosion inhibitor and toughening agent.

[0073] Optionally, based on the total mass of the organic mixture, the amount of the toughening agent added is 5wt% to 10wt%; the amount of the corrosion inhibitor added is 5wt% to 10wt%. Understandably, in other embodiments, the amounts of the corrosion inhibitor and the toughening agent added may be parameters commonly used in the art.

[0074] In some specific embodiments, the amount of starch added is 30 wt% to 35 wt% based on the total weight of the organic mixture. Understandably, an appropriate amount of starch is added to the organic mixture so that the total weight percentage of starch in the organic mixture reaches 60% to 65%, thereby increasing the viscosity and compatibility of the organic mixture, which is convenient for subsequent film blowing.

[0075] In some specific embodiments, the mixing method is stirring and mixing.

[0076] In some specific embodiments, the mixing time is 15 min to 20 min.

[0077] Step S22: Extruding and granulating the premix.

[0078] In some specific embodiments, the temperature of extrusion granulation is 58° C. to 62° C. Optionally, the temperature of extrusion granulation is 60° C.

[0079] Understandably, turning kitchen waste into solid particles facilitates storage and transportation, and reduces the risk of secondary pollution.

[0080] Step S30: using the organic solid particles to form a film to prepare the bio-based plastic film product.

[0081] In some implementations, step S30 includes steps S31 and S32.

[0082] Step S31: melting the organic solid particles.

[0083] Step S32: blowing or drawing a film on the melted solid particles.

[0084] In some embodiments, the temperature of the blown film is 60° C. to 80° C. Optionally, the temperature of the blown film is 60° C. to 70° C.

[0085] In some of the embodiments, the method for preparing the bio-based plastic film product further includes step S40.

[0086] Step S40: printing the bio-based plastic film product.

[0087] It is understandable that in step S40, patterns or texts may be printed on the inner surface or outer surface of the plastic product according to usage requirements.

[0088] In some of the embodiments, the method for preparing the bio-based plastic film product further includes step S50.

[0089] Step S50: cutting the above-mentioned bio-based plastic film product to prepare bio-based plastic bags or bundled bio-based plastic films.

[0090] Traditional bio-based degradable plastic bags use starch (food) as raw materials, but the large-scale use of starch not only leads to increased production costs, but also involves national food security issues, making it difficult to expand the market for starch-based degradable plastic bags. In this application, kitchen waste is used as raw materials to turn kitchen waste into a reusable resource, which has the advantages of low price; the price of plastic bags of the same specifications is only 1 / 4 to 1 / 6 of that of starch-based degradable plastic bags.

[0091] Kitchen waste comes from restaurants, canteens, etc., and its main components include oil and protein. The collection time of kitchen waste is relatively long, usually 1 to 3 days. During the collection process, it is very easy to produce a large amount of thiols, ammonia, hydrogen sulfide, methyl sulfide, trimethylamine, formaldehyde, styrene, butyric acid and phenols that are harmful to human health, and there is also a risk of bacterial growth. If kitchen waste is used instead of starch as the raw material for bio-based plastic film products, deamination, deoxygenation and sterilization steps are required during the manufacturing process, which is a complicated process; the preparation cost is relatively higher, and the performance of the prepared bio-based plastic film products is unstable.

[0092] The organic mixture obtained by specific treatment of kitchen waste has a composition similar to that of the raw materials of traditional bio-based plastic film products, and can be used to replace the raw materials of traditional bio-based plastic film products. The prepared bio-based plastic film products can meet the performance requirements of different application scenarios. At the same time, converting kitchen waste into raw materials for bio-based plastic film products has achieved the goal of turning waste into treasure, which is in line with the national green economy and circular economy industrial policies.

[0093] The method for preparing the bio-based plastic film product of the present application has at least the following advantages:

[0094] (1) The raw materials are abundant and the cost is extremely low, which greatly reduces the total production cost of bio-based plastic film products.

[0095] (2) The preparation of bio-based plastic film products can be completed within 4 hours, and the entire preparation process can be completed with the help of integrated processing equipment, saving a lot of labor costs.

[0096] (3) The recycling and harmless treatment of discarded kitchen waste has been achieved.

[0097] (4) The performance of the prepared bio-based plastic film products can meet the usage requirements in different scenarios.

[0098] Other embodiments of the present application provide a bio-based plastic film product prepared by the above-mentioned method for preparing a bio-based plastic film product.

[0099] In some embodiments, the bio-based plastic film products include bio-based plastic bags and bio-based plastic films, etc. It is understandable that the bio-based products of the present application include but are not limited to the above forms, and may also be in other forms.

[0100] In some specific embodiments, the bio-based plastic film product has a thickness of 0.02 mm to 0.35 mm.

[0101] In some specific embodiments, the bio-based plastic film includes agricultural mulch film and agricultural greenhouse film.

[0102] In some specific examples, the thickness of agricultural ground film is 0.02mm~0.05mm; the thickness of agricultural greenhouse film is 0.15mm~0.35mm.

[0103] The above-mentioned plastic products can be completely degraded in the natural environment and can be recycled, realizing the transformation of household kitchen waste into treasure and resource regeneration, which is in line with the national green economy and circular economy industrial policies.

[0104] The present application will be further described below in conjunction with specific examples and comparative examples, but they should not be construed as limiting the scope of protection of the present application. The raw materials involved in the following specific examples, unless otherwise specified, can all be sourced from commercial sources, the instruments used, unless otherwise specified, can all be sourced from commercial sources, and the processes involved, unless otherwise specified, are all conventionally selected by those skilled in the art.

[0105] Embodiment 1:

[0106] according to Figure 1 The process shown in the figure is to prepare a bio-based plastic bag, which specifically includes the following steps:

[0107] (1) Crushing: Put the kitchen waste into the crusher for the first crushing to obtain crushed waste with an average particle size of 5 mm.

[0108] (2) Solid-liquid separation: The crushed garbage is subjected to the first water removal treatment to remove more than 50% of the water and oil in the crushed garbage, and obtain semi-wet garbage with a water content of 50wt%; at the same time, the squeezed water and oil are discharged into the sewage station oil separator tank and finally sent to the sewage treatment station.

[0109] (3) Extrusion: The semi-wet garbage is subjected to a second crushing treatment and a second water removal treatment through an extrusion device to obtain granular garbage with an average particle size of 3 mm and a water content of 3 wt%. The squeezed water is discharged into the grease trap of the sewage station and finally sent to the sewage treatment station.

[0110] (4) Homogenization and grinding: The granular waste is homogenized to a water content of 0.5 wt%, and then ground into an organic matter mixture with a particle size of about 600 mesh.

[0111] (5) Granulation: Add pure starch to the organic mixture until the starch content is greater than 60%, and add corrosion inhibitor and toughening agent to the organic mixture, stir thoroughly for 15 minutes to make it homogeneous; control the temperature to 60°C for granulation to prepare organic solid particles.

[0112] (6) Film blowing: The organic solid particles are blown into a film at 80°C to produce a bio-based plastic film with a thickness of 0.04 mm.

[0113] (7) Printing: Printing patterns on the outer surface of the bio-based plastic film according to user requirements.

[0114] (8) Bag cutting and packaging: The printed bio-based plastic film is cut into bio-based plastic bags.

[0115] The thermal stability and weather resistance of the bio-based plastic bag prepared in this example are shown in Table 1. The test methods for thermal stability and weather resistance are both carried out in accordance with GB / T19277.1-2011.

[0116] Table 1

[0117]

[0118] The above results show that the bio-based plastic film products prepared by the method of the present application have good thermal stability and weather resistance, and can meet the use requirements of plastic products in different industries; at the same time, the bio-plastic products prepared by the present application can be completely degraded and recycled under natural conditions. In addition, the method of the present application realizes the resource recycling of household kitchen waste and reduces the harm caused by kitchen waste to the environment.

[0119] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0120] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for preparing a bio-based plastic film product, characterized in that: The steps include: Crush the kitchen waste to obtain crushed waste; Performing solid-liquid separation on the crushed garbage to obtain semi-wet garbage; The semi-wet garbage is squeezed to obtain granular garbage; the water content of the granular garbage is 3wt% to 5wt%; The granular garbage is homogenized and ground to obtain an organic mixture; the water content of the organic mixture is 0.3wt% to 0.5wt%, and the particle size of the organic mixture is 400 mesh to 600 mesh; Mixing the organic mixture with starch, corrosion inhibitor and toughening agent and performing extrusion granulation to prepare organic solid particles; and The organic solid particles are used to make films to prepare the bio-based plastic film products.

2. The method for preparing a bio-based plastic film product according to claim 1, characterized in that: Calculated by mass percentage, the organic mixture includes 70wt% to 80wt% of plant crude fiber and 20wt% to 30wt% of starch.

3. The method for preparing a bio-based plastic film product according to claim 1, characterized in that: The water content of the semi-wet garbage is 40wt% to 50wt%.

4. The method for preparing a bio-based plastic film product according to claim 1, characterized in that: The preparation method satisfies at least one of the following conditions (1) to (2): (1) The average particle size of the crushed garbage is 3.1 mm to 5 mm; (2) The average particle size of the granular garbage is 1 mm to 3 mm.

5. The method for preparing a bio-based plastic film product according to any one of claims 1 to 4, characterized in that: Extrusion granulation includes the following steps: Detecting the mass percentage of starch in the organic matter mixture; Adding starch, a corrosion inhibitor and a toughening agent to the organic mixture so that the total mass percentage of starch in the organic mixture is 60wt% to 65wt%; The organic mixture is mixed with starch, a corrosion inhibitor and a toughening agent to obtain a premix; and the premix is ​​extruded and granulated.

6. The method for preparing a bio-based plastic film product according to claim 5, characterized in that: The toughening agent includes one or more of polylactic acid and polyhydroxyalkanoic acid ester.

7. The method for preparing a bio-based plastic film product according to claim 5, characterized in that: The temperature of the extrusion granulation is 58°C to 62°C.

8. The method for preparing a bio-based plastic film product according to any one of claims 1 to 4, 6 to 7, characterized in that: The process of preparing a membrane using the organic solid particles comprises the following steps: Melting the organic solid particles and then performing film blowing or film drawing; Wherein, the temperature of the film blowing is 60℃~80℃; the temperature of the film drawing is 60℃~80℃.

9. A bio-based plastic film product, characterized in that: The bio-based plastic film product is prepared by the method for preparing the bio-based plastic film product according to any one of claims 1 to 8.

Images