CN113754938B

CN113754938B - Fully-degradable plastic film and preparation method thereof

Info

Publication number: CN113754938B
Application number: CN202111008367.4A
Authority: CN
Inventors: 徐德胜
Original assignee: Anhui Lelang Environmental Protection New Material Co ltd
Current assignee: Anhui Lelang Environmental Protection New Material Co ltd
Priority date: 2021-08-31
Filing date: 2021-08-31
Publication date: 2023-06-06
Anticipated expiration: 2041-08-31
Also published as: CN113754938A

Abstract

The application relates to the technical field of plastic films, and particularly discloses a fully-degradable plastic film and a preparation method thereof. The fully degradable plastic film comprises the following components in parts by weight: 10-40 parts of thermoplastic starch; 60-90 parts of high polymer resin; 3-8 parts of photodegradation agent; 3-8 parts of a biodegradation agent; 1-3 parts of inorganic powder filler; 0.5-2 parts of heat stabilizer; the high polymer resin is one or more of polyethylene, polypropylene, polyvinyl chloride, polystyrene, vinyl acetate and ethylene-vinyl acetate copolymer; the photodegradation agent is formed by mixing a transition metal organic compound and a transition metal inorganic compound according to the weight ratio of 1 (0.1-1); the biodegradation agent is a polybasic organic acid. The plastic film has high degradation rate, can be completely degraded, and is favorable for reducing the pollution of plastic materials to the environment.

Description

Fully-degradable plastic film and preparation method thereof

Technical Field

The application relates to the technical field of plastic films, in particular to a fully degradable plastic film and a preparation method thereof.

Background

The plastic film is made of polyvinyl chloride, polyethylene, polypropylene, polystyrene and other resins, is an indispensable article in daily life, has been widely applied to the fields of food, medicine, chemical industry, agriculture and the like, and is often used for manufacturing packaging bags, garbage bags, mulching films and the like.

The use amount is huge, so that serious resource waste is caused, and the environment pollution is remarkable, and the environment pollution is called white pollution. Plastic film products can only rot after being buried under the ground for about 200 years, and soil is seriously polluted. If the incineration treatment is adopted, harmful smoke dust and toxic gas can be generated to pollute the atmosphere.

Currently, most of the degradable plastic films on the market are only 10-15% of the degradable components are added, but 85-90% of the components still cannot be completely degraded, and such materials are called incomplete biodegradable plastics. The starch-based plastic film is one of the above-mentioned incompletely biodegradable plastics, and is made of starch, general-purpose plastic resin and other additives. The degradation of starch-based plastic films mainly relies on the decomposition of starch, but the plastic substrate is still not degradable and is difficult to recycle, and the plastic film still causes pollution to the environment.

Disclosure of Invention

In order to improve the degradation rate of the plastic film and enable the plastic film to be completely degraded, the application provides a fully-degradable plastic film and a preparation method thereof.

In a first aspect, the present application provides a fully degradable plastic film, which adopts the following technical scheme:

the fully degradable plastic film comprises the following components in parts by weight:

10-40 parts of thermoplastic starch;

60-90 parts of high polymer resin;

3-8 parts of photodegradation agent;

3-8 parts of a biodegradation agent;

1-3 parts of inorganic powder filler;

0.5-2 parts of heat stabilizer;

the high polymer resin is one or more of polyethylene, polypropylene, polyvinyl chloride, polystyrene, vinyl acetate and ethylene-vinyl acetate copolymer;

the photodegradation agent is formed by mixing a transition metal organic compound and a transition metal inorganic compound according to the weight ratio of 1 (0.1-1);

the biological degradation agent is a polybasic organic acid;

the inorganic powder filler is one or more of superfine tourmaline powder, nano silicon dioxide and nano sepiolite powder;

the heat stabilizer is one or more of zinc glycerate, zinc stearate and magnesium stearate.

By adopting the technical scheme, the photodegradation agent and the biodegradation agent are added simultaneously in the process of preparing the plastic film, and exert better synergistic effect, so that the plastic film is effectively degraded. The photodegradation agent can promote the high molecular resin to be oxidized and degraded under the conditions of light and heat, the molecular weight of high molecular resin materials such as polyethylene is reduced to below 1 ten thousand, then the biodegradation agent can promote microorganisms in soil to further degrade small molecular polymers formed after the oxidative degradation, and the small molecular polymers are degraded into water, carbon dioxide and humus, so that the plastic film is completely degraded, and no pollution is caused to the environment.

The photodegradation agent is formed by mixing a transition metal organic compound and a transition metal inorganic compound, wherein the transition metal organic compound can exert a better oxidative degradation effect under visible light, and the transition metal inorganic compound can exert a better oxidative degradation effect under ultraviolet light.

The thermoplastic starch in the raw materials and the high polymer resin such as polyethylene have better compatibility, which is beneficial to improving the comprehensive performance of the plastic film, simultaneously, the plastic film is convenient to process, is not easy to damage during blow molding or tape casting, and reduces the production loss of the plastic film.

Preferably, the photodegradant is formed by mixing a transition metal organic compound and a transition metal inorganic compound according to a weight ratio of 1 (0.2-0.6).

By adopting the technical scheme, the degradation rate of the plastic film can be further improved by further optimizing the weight ratio of the transition metal organic compound and the transition metal inorganic compound in the photodegradant, so that the degradation response of the plastic film is quicker, and the degradation effect detection shows that only 52-56 days are needed. The plastic film can be obviously degraded.

Preferably, the transition metal organic compound is one or more of formate, acetate, isooctanoate, laurate and stearate of transition metal element.

Preferably, the transition metal organic compound is one or more of ferric diethyl dithiocarbamate, ferric stearate and cerium stearate.

By adopting the technical scheme, the transition metal organic compound is a visible light catalytic degradation component, and can promote the oxidative degradation of high polymer resins such as polyethylene and the like under the catalysis of visible light to form a small polymer chain segment with the molecular weight less than 1 ten thousand, so that the plastic film is effectively degraded.

Preferably, the transition metal inorganic compound is a transition metal oxide and/or an transition metal sulfide.

Preferably, the transition metal inorganic compound is one or more of titanium dioxide, zinc oxide and zinc sulfide.

By adopting the technical scheme, the transition metal inorganic compound is mainly an ultraviolet light catalytic degradation component, and the ultraviolet light catalytic effect promotes the oxidative decomposition of high polymer resins such as polyethylene, and the photodegradation efficiency of the high polymer resins such as polyethylene can be further improved when the transition metal inorganic compound is compounded with the transition metal organic compound.

Preferably, the particle size of the transition metal inorganic compound is 5-100nm.

By adopting the technical scheme, the specific surface area of the transition metal inorganic compound can be increased by controlling the particle size of the transition metal inorganic compound within the range, the light absorption efficiency is improved, the speed of photocatalysis reaction is further improved, and high polymer resins such as polyethylene and the like are rapidly degraded. As shown by the degradation effect test, when the transition metal inorganic compound is titanium dioxide with the wavelength of 30nm, the plastic film is obviously degraded at the 42 th day of the initial test.

Preferably, the polybasic organic acid is one or more of citric acid, lactic acid, succinic acid and malic acid.

Preferably, the preparation method of the thermoplastic starch comprises the following steps: mixing starch, silane coupling agent 3-5 wt% and urea 3-5 wt% at 100-120 deg.c, cooling and crushing to obtain the final product.

The starch is corn starch, potato starch, wheat starch, etc.

By adopting the technical scheme, after the starch and urea are mixed, heat energy and mechanical energy are applied to break hydrogen bonds among starch molecules, so that the crystal structure of starch particles is disintegrated through melting and shearing actions, and disordered continuous phases are formed by the starch molecular chains, thereby improving the processing performance and the service performance of the starch. Meanwhile, urea itself is used as a fertilizer component, and is harmless to the environment.

The particle size of the thermoplastic starch is 40-200 meshes.

By adopting the technical scheme, the particle size of the thermoplastic starch is controlled to be 40-200 meshes, so that the synergistic filling effect among thermoplastic starch particles can be fully exerted, the compatibility of the thermoplastic starch and other component raw materials is further improved, and the production processing performance and various mechanical properties of the plastic film are improved.

In a second aspect, the present application provides a method for preparing a fully degradable plastic film, which adopts the following technical scheme: the preparation method of the fully degradable plastic film comprises the following steps:

s1, mixing materials: stirring and mixing the high polymer resin, the photodegradant and the photodegradant, adding the heat stabilizer, the inorganic powder filler and the thermoplastic starch, and continuously stirring and mixing to obtain a primary mixed material;

s2, extrusion granulation: extruding and granulating the primary mixed material obtained in the step S1 to obtain a master batch;

s3, blow molding: and (3) blow molding the master batch obtained in the step (S2) to obtain the product.

By adopting the technical scheme, the preparation method has simple steps, wide raw material sources and easy obtainment, and can realize large-scale industrial production. The polymer resin is fully contacted with the degradation agent by firstly mixing the polymer resin with the photodegradation agent and the biodegradation agent and then adding other raw material components, so that the degradation rate of the later-stage plastic film is improved.

In summary, the present application has the following beneficial effects:

1. the photodegradation agent and the biological degradation agent are simultaneously added and are matched in the full degradation process of the plastic film, the photodegradation agent firstly oxidizes and degrades the plastic film into small molecular polymers under the conditions of light and heat, and then the biological degradation agent promotes microorganisms in soil to continuously degrade the small molecular polymers into water, carbon dioxide and humus, so that the plastic film is completely degraded;

2. the photodegradation agent is formed by mixing a transition metal organic compound and a transition metal inorganic compound, wherein the transition metal organic compound is a visible light catalytic degradation component, the transition metal inorganic compound is an ultraviolet light catalytic degradation component, and the transition metal organic compound and the ultraviolet light catalytic degradation component exert synergistic promotion effect under sunlight, so that the response speed of degradation of the plastic film can be obviously improved, and the degradation rate is improved;

3. according to the preparation method, the starch is modified, so that the processing performance and the service performance of the starch are improved, and the thermoplastic starch obtained after modification has better compatibility with other components, so that the comprehensive performance of the plastic film is improved.

Detailed Description

The present application is described in further detail below with reference to examples.

The raw materials used in the examples of the present application are commercially available except for the following specific descriptions:

the starch is corn starch, is obtained from Anhui Guanglan biotechnology Co., ltd, has an industrial grade, the content of the starch is more than or equal to 99%, and the product number is YMDF002;

the silane coupling agent is a silane coupling agent KH550, which is obtained from Jinan Rong chemical industry Co., ltd;

urea is obtained from Shandong Haohao New Material Co., ltd, and the model is HY741;

the low density polyethylene is obtained from Dongguan Jiajia plastic raw material limited company, with the brand of 1002AY and the product of LL 1002AY;

commercially available thermoplastic starch available from Souzhou and plastic technologies Inc. under the trademark TPS;

acetylacetone was obtained from the Wohan's biosciences Co., ltd, CAS number 14024-18-1, 99% content;

the ferric chloride is obtained from Ji-nan Xin-Nuo chemical industry Co., ltd, the content is 98%, and the grain size is 100 meshes;

oxalic acid is obtained from Anhui Guanglan biotechnology limited, industrial grade, and the content is 99.6%;

the nano silicon dioxide is obtained from the silicon industry limited company of the dream of Boai county, the industrial grade, the content is more than or equal to 99 percent, and the model is 180X;

zinc glycerolate is obtained from Hubei Xinrun chemical Co., ltd, and has a content of 99% and a zinc content of 42+ -0.5%;

iron diethyldithiocarbamate is available from the Beijing carboline technologies Co., ltd, product number D0489;

iron stearate was obtained from the Beijing Baoling technologies Co., ltd, product number 26-2622;

cerium stearate is obtained from the chemical industry Co.Ltd of Zibo Lu Chuan, the cerium content is 11.0+/-0.5 percent, and the particle size is 200 meshes;

titanium dioxide was obtained from Guangdong source epitaxial powder Co., ltd, 2000 mesh, model TR50;

zinc oxide was obtained from Shanghai Ala Biochemical technologies Co., ltd, product number Z111841;

the zinc sulfide is obtained from Zhejiang submicron nano technology Co., ltd, the purity is 99.99 percent, and the grain diameter is 1 mu m;

citric acid was obtained from Shanghai Ala Biochemical technologies Co., ltd, product number C108869;

succinic acid was obtained from Shanghai Ala Biochemical technologies Co., ltd, product number S108853;

the screw extruder is obtained from Nanjing Kelter mechanical equipment Co., ltd, and the model is SHJ-75D;

the film blowing machine is obtained from Zhejiang de penguin mechanical Co., ltd, and the model is DZPP-2L900.

Preparation of raw materials

Preparation example 1

The thermoplastic starch comprises the following components and the corresponding weight of the components are shown in table 1, and is prepared by the following steps:

mixing starch, silane coupling agent and urea at 110 ℃, naturally cooling to room temperature, pulverizing, and sieving with 40 mesh and 200 mesh sieve respectively to obtain thermoplastic starch with particle size range of 40-200 mesh.

PREPARATION EXAMPLES 2 to 5

The thermoplastic starch was prepared in the same manner as in preparation example 1 except that the amounts of the components used were different, and the respective components and their respective weights in preparation examples 2 to 5 are shown in Table 1.

TABLE 1 Components in preparation examples 1-5 and weights (kg)

Preparation example 6

A thermoplastic starch differs from preparation example 4 in that the thermoplastic starch of preparation example 6 has a particle size of-20 mesh.

Preparation example 7

A thermoplastic starch differs from preparation example 4 in that the thermoplastic starch of preparation example 7 has a particle size of-40 mesh.

Examples

Example 1

The fully degradable plastic film is prepared by the following steps of:

s1, mixing materials: stirring and mixing the high polymer resin, the photodegradant and the biodegradation agent for 10min at the temperature of 120r/min and 50 ℃, adding the heat stabilizer, the inorganic powder filler and the thermoplastic starch, and continuously stirring and mixing for 5min under the conditions to obtain a primary mixed material;

s2, extrusion granulation: extruding and granulating the primary mixed material obtained in the step S1 by using a screw extruder, wherein the extrusion temperature is 140-165 ℃ to obtain a master batch;

s3, blow molding: and (3) carrying out blow molding on the master batch obtained in the step (S2) by using a film blowing machine, wherein the temperature is 170-195 ℃ and the pressure is 10-12MPa during film blowing, and the fully-degradable plastic film is obtained, and the thickness of the fully-degradable plastic film is 20 mu m.

Wherein the thermoplastic starch is commercially available from Suzhou and plastic technologies Co., ltd;

the high polymer resin is low-density polyethylene;

the photodegradation agent is formed by mixing a transition metal organic compound and a transition metal inorganic compound according to the weight ratio of 1:0.1, wherein the transition metal organic compound is ferric acetylacetonate, and the transition metal inorganic compound is ferric chloride;

the biodegradation agent is oxalic acid;

the inorganic powder filler is nano silicon dioxide;

the heat stabilizer is zinc glycerolate.

Examples 2 to 6

A fully degradable plastic film is different from example 1 in that the components and the corresponding parts by weight are shown in Table 1.

Table 2 the components and weights (kg) thereof in examples 1 to 6

Examples 7 to 10

A fully degradable plastic film was prepared in the same manner as in example 3 except that the weight ratio of the transition metal organic compound and the transition metal inorganic compound in the photodegradant was changed, and the weight ratio of the transition metal organic compound and the transition metal inorganic compound in the photodegradant was as shown in Table 3.

TABLE 3 composition of photodegradants in examples 3, 7-10

Examples 11 to 14

A fully degradable plastic film was prepared in the same manner as in example 8 except that the specific kinds of the transition metal organic compound and the transition metal inorganic compound were changed as shown in Table 4.

TABLE 4 composition of photodegradants in examples 8, 11-14

Example 15

A fully degradable plastic film is the same as in example 13 except that the transition metal inorganic compound is of the same kind as in example 13, and in example 14, the transition metal inorganic compound is nano titanium dioxide, which is obtained from Shanghai Hui Jing sub-nano New Material Co., ltd, the content is 99.9%, and the particle size is 30nm.

Example 16

A fully degradable plastic film was the same as in example 15 except that the specific usage of the biodegradable agent was the same as in example 15, and the biodegradable agent was citric acid.

Example 17

A fully degradable plastic film is the same as in example 15 except for the specific use of the biodegradable agent, in example 16, the biodegradable agent is composed of citric acid and succinic acid mixed in a weight ratio of 1:1.

Examples 18 to 24

A fully degradable plastic film was prepared in the same manner as in example 17 except that thermoplastic starch was used in the same manner as in example 5.

TABLE 5 use of thermoplastic starch in examples 17-24

Comparative example

Comparative example 1

A plastic film was different from example 1 in that no photodegradants and no biodegradation agent were added in the process of producing the plastic film.

Comparative example 2

A plastic film was different from example 1 in that no photodegradant was added in the process of producing the plastic film.

Comparative example 3

A plastic film was different from example 1 in that no biodegradable agent was added during the preparation of the plastic film.

Comparative example 4

A plastic film was the same as in example 1 except that the photodegradants were different in kind, and the photodegradants in comparative example 4 were only transition metal organic compounds, specifically, ferric acetylacetonate.

Comparative example 5

A plastic film was the same as in example 1 except that the photodegradants were different in kind, and the photodegradants in comparative example 5 were only transition metal inorganic compounds, specifically ferric chloride.

Comparative example 6

A plastic film was prepared in the same manner as in example 3 except that the weight ratio of the transition metal organic compound to the transition metal inorganic compound in the photodegradant was changed, and in comparative example 6, the weight ratio of the transition metal organic compound to the transition metal inorganic compound in the photodegradant was 1:0.05.

Comparative example 7

A plastic film was the same as in example 3 except that the weight ratio of the transition metal organic compound and the transition metal inorganic compound in the photodegradant was different, and in comparative example 7, the weight ratio of the transition metal organic compound and the transition metal inorganic compound in the photodegradant was 1:1.2.

Performance test

The plastic films prepared in examples 1 to 24 and comparative examples 1 to 7 were taken as test subjects, samples having a cut-out specification of 10cm×10cm were taken as test samples, and the degradation properties of the plastic films were tested under the same field natural conditions by referring to the methods in GB/T20197-2006 "definition, classification, identification and degradation Property Requirements for degraded plastics", and the test results are shown in the following Table 6. The testing site is selected from abandoned agricultural land in Xintai city of Shandong province, and the testing time is 6 months.

TABLE 6 degradation Performance test results

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As can be seen from the test data in table 6: the plastic films prepared in the examples 1-24 have good degradability, and the detection test results show that the plastic film test samples are obviously degraded at the latest at the 66 th day of the initial test, namely the plastic films prepared in the examples 1 and 6; the plastic film produced in example 25 was the fastest possible to undergo significant degradation on day 25 of the initial test. And after the test is finished for 6 months, the plastic films prepared in all the examples can be completely degraded to obtain test samples, and no plastic film remains in the soil. In contrast, the plastic films prepared in comparative examples 1 to 7 were degraded to a different extent in time and after the test was completed, as compared with the plastic film prepared in example 1.

The difference between example 1 and comparative example 1 is that the comparative example 1 was prepared without adding a photodegradant and a biodegradable agent, and it can be seen from table 6 that the sample of comparative example 1 was significantly degraded only on the 122 th day of the start of the test, 56 days later than the sample of example 1, and the sample of comparative example 1 was only broken after the end of the test, and the molecular weight test showed that the decrease in the weight average molecular weight of polyethylene was not significant, indicating that the plastic film was not effectively degraded. The reason for this phenomenon is that the plastic film produced in comparative example 1 was degraded only by the thermoplastic starch component in the raw material during the degradation test, so that the plastic film was broken, and the plastic matrix component, i.e., the low-density polyethylene, was not degraded effectively. Thus, it is shown that the degradability of the plastic film can be effectively improved and the plastic film can be completely degraded by adding the photodegradable agent and the biodegradable agent in the embodiment 1.

The difference between example 1 and comparative example 2 is that comparative example 2 did not add photodegradation agent during the preparation of plastic film, and it can be seen in combination with table 6 that the sample of comparative example 2 was significantly degraded at 115 days from the start of the test, 49 days later than the sample of example 1, and the sample of comparative example 2 was only broken after the end of the test, and the molecular weight test showed that the decrease in weight average molecular weight of polyethylene was not significant, indicating that the plastic film was not effectively degraded. The reason for analysis is that the photodegradant is to oxidize and degrade polyethylene in the plastic film into small molecular polymer with weight average molecular weight below 1 ten thousand through the action of light and heat in nature, then promote the microorganisms in the soil to continuously degrade the small molecular polymer into water, carbon dioxide and humus under the promotion action of the photodegradant, so that the complete degradation of the plastic film is realized, and the photodegradant is not added in comparative example 2, so that the oxidative degradation of the plastic film is greatly weakened, and the plastic film cannot be effectively degraded.

The difference between example 1 and comparative example 3 is that in the process of preparing the plastic film in comparative example 3, no biodegradation agent is added, and it can be seen from table 6 that the sample of comparative example 3 is degraded into powder after the test is finished, and the molecular weight test shows that the weight average molecular weight of the main component is reduced to less than 1 ten thousand, indicating that the plastic film is effectively oxidatively degraded, but not effectively biodegraded. The reason for analysis is that the photodegradant promotes the polyethylene in the plastic film to be oxidized and degraded into a small molecular polymer with weight average molecular weight of less than 1 ten thousand, but the degradation speed of microorganisms in soil on the small molecular polymer generated by oxidative degradation is slower because the photodegradant is not added, so that after the test time of 6 months, the plastic film is not effectively biodegraded, and the degradability of the plastic film is affected.

The difference between example 1 and comparative example 4 is that the photodegradants in comparative example 4 are only transition metal organic compounds, specifically iron acetylacetonate, and it can be seen in combination with table 6 that the sample of comparative example 4 is significantly degraded after 87 days from the start of the test, 21 days later than the sample of example 1, and that a small portion of plastic film remains in the soil after the end of the test, but the molecular weight distribution gradient of the main component in the plastic film residue is relatively uniform as seen by the molecular weight detection of the remaining film, and that an excessive component of a certain molecular weight does not occur. From this, the following can be concluded: the plastic film of comparative example 4 was completely degradable but the degradation rate was slower than that of example 1.

The difference between example 1 and comparative example 5 is that the photodegradants in comparative example 5 are only transition metal inorganic compounds, specifically ferric chloride, and it is seen from the data in table 6 that the detection of the plastic film sample of comparative example 5 is similar to that of comparative example 4, and the degradation rate of the plastic film of comparative example 5 is slower than that of comparative example 4. The reason for this analysis is probably because the transition metal organic compound is mainly a visible light degradation agent, and the transition metal inorganic compound is mainly an ultraviolet light degradation agent, and when any of the above-mentioned is used alone as a photodegradation agent, the promotion effect on photo-and thermo-oxidative degradation is limited, and thus the degradation rate of the plastic film is affected.

The difference between examples 3, 7-10 and comparative examples 6-7 is that the weight ratio of the transition metal organic compound to the transition metal inorganic compound in the photodegradants is different, and it is known from the data of Table 6 that, in the process of producing a plastic film, when the photodegradants are composed of the transition metal organic compound and the transition metal inorganic compound in a mixed manner in a weight ratio of 1 (0.1-1), the degradability of the plastic film can be remarkably improved, and particularly when the weight ratio of the transition metal organic compound to the transition metal inorganic compound is 1 (0.2-0.6), the degradation rate of the plastic film produced is the best. The weight ratio of the transition metal organic compound to the transition metal inorganic compound in the photodegradation agent of comparative example 6 is 1:0.05; the weight ratio of the transition metal organic compound to the transition metal inorganic compound in the photodegradant of comparative example 7 was 1:1.2, and it can be seen from the data of table 6 that the time for which the plastic film samples of comparative example 6 and comparative example 7 were significantly degraded was later than that of example 3.

The present embodiment is merely illustrative of the present application and is not intended to be limiting, and those skilled in the art, after having read the present specification, may make modifications to the present embodiment without creative contribution as required, but is protected by patent laws within the scope of the claims of the present application.

Claims

1. The fully degradable plastic film is characterized by comprising the following components in parts by weight:

10-40 parts of thermoplastic starch;

60-90 parts of high polymer resin;

3-8 parts of photodegradation agent;

3-8 parts of a biodegradation agent;

1-3 parts of inorganic powder filler;

0.5-2 parts of heat stabilizer;

the high polymer resin is polyethylene;

the photodegradation agent is formed by mixing a transition metal organic compound and a transition metal inorganic compound according to the weight ratio of 1:0.4;

the transition metal organic compound is diethyl ferric dithiocarbamate;

the transition metal inorganic compound is titanium dioxide;

the biological degradation agent is a polybasic organic acid;

the preparation method of the thermoplastic starch comprises the following steps: mixing starch, silane coupling agent 3-5 wt% and urea 3-5 wt% at 100-120 deg.c, cooling and crushing to obtain the final product.

2. The fully degradable plastic film according to claim 1, wherein the particle size of the transition metal inorganic compound is 5-100nm.

3. The fully degradable plastic film according to claim 1, wherein the polybasic organic acid is one or more of citric acid, succinic acid, malic acid.

4. A method for producing a fully degradable plastic film according to any one of claims 1 to 3, characterized by comprising the steps of: