CN117626703B - Degradable composite barrier coating applied to paper-based material - Google Patents

Abstract

The invention discloses a degradable composite barrier coating applied to paper-based materials, which relates to the technical field of the degradable composite barrier coating, and comprises the steps of dissolving 20g of PVA1799 in 100ml of DMF, and then placing the dissolved PVA in a water bath at 95 ℃ for stirring until the PVA is completely dissolved to obtain 20% PVA aqueous solution; adding 0.2g of preservative Nepal gold butyl ester into the PVA aqueous solution at normal temperature, stirring for 10min, adding 0.2ml of concentrated hydrochloric acid, stirring for ten min, inspecting quality, and discharging; adding 10gPHB to the solution, placing in a water bath at 80 ℃, adding 3.27g of IPDI, starting stirring until suspended substances in the solution are completely dissolved, obtaining PVA-PHB composite material, the prepared PVA-PHB composite material has ideal film forming property and cohesiveness, the molecular chain of the composite material is orderly stacked due to the existence of a large number of strong polar hydroxyl groups in and among the molecules, so that the diffusion rate of gas in the film is slowed down, and the diffusion path is prolonged due to the higher crosslinking degree, so that the gas barrier property of the packaging film is improved.

Description

A degradable composite barrier coating applied to paper-based materials

Technical Field

The present invention relates to the technical field related to degradable composite barrier coatings, and in particular to a degradable composite barrier coating applied to a paper-based material.

Background Art

At present, with the implementation of the "plastic ban" and the continuous improvement of people's environmental awareness, the food packaging industry has begun to use paper-based materials such as paper and cardboard to replace synthetic polymers. However, like conventional polymer packaging materials, paper-based packaging also needs to have high strength and high barrier functions. For food packaging, water vapor and oxygen in the atmosphere are the key to penetrating packaging materials and causing food to deteriorate. The current methods to improve the barrier properties of paper-based packaging are impregnation with oil, wax, resin, latex, etc.; depositing a dense oxide film on the surface; compounding plastic with paper to prepare paper-plastic composite materials. Most of the materials used are non-degradable, which will make the recycling and repulping of paper products difficult and not environmentally friendly; the surface coating method is simple and easy to produce, especially the use of degradable polymers as coating materials is the current main development direction.

Degradable materials are a type of material that can cause internal polymer unzipping through external forces (light, heat, microorganisms, mechanical action), decomposing large molecular polymers into small molecular polymers. Commonly used degradable polymer coatings include nanocellulose, polyhydroxybutyrate (PHB), polylactic acid (PLA), polyvinyl alcohol (PVA), etc.

In the prior art, PVA is easy to dissolve, swell and absorb moisture in water, and usually has a high water vapor permeability. In addition, when the relative humidity of the environment is high, its oxygen permeability will also increase significantly by swelling and absorbing moisture. Taking a PVA film with a thickness of 6 μm as an example, when the relative humidity rises from 0% RH to 55% RH, its oxygen permeability increases by more than 5 times, and when the PHB concentration exceeds 10%, its moisture absorption rate, water absorption rate, water vapor permeability and surface roughness are all reduced, and the surface hydrophobicity increases. In order to solve the above-mentioned problems, a degradable composite barrier coating for use on paper-based materials is now provided.

Summary of the invention

The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

In view of the problems existing in the water bath of the degradable composite barrier coating applied to the paper-based material, the present invention is proposed.

Therefore, the object of the present invention is to provide a degradable composite barrier coating for use on paper-based materials.

In order to solve the above technical problems, the present invention provides the following technical solution: the preparation method of the degradable composite barrier coating comprises the following steps:

S1. Take 20g PVA1799 and dissolve it in 100ml DMF. After dissolution, place it in a 95°C water bath and stir until PVA is completely dissolved to obtain a 20% PVA aqueous solution;

S2. Add 0.2 g of preservative Nepal gold butyl ester to the PVA aqueous solution at room temperature, stir for 10 minutes, then add 0.2 ml of concentrated hydrochloric acid, stir for ten minutes, perform quality inspection, and discharge;

S3. Add 10 g PHB to the above solution, place it in a water bath at 80° C., add 3.27 g IPDI, and start stirring until the suspended matter in the solution is completely dissolved to obtain a PVA-PHB composite material.

Another object of the present invention is to provide a water bath for the degradable composite barrier coating applied to paper-based materials.

The present invention provides the following technical solution: it comprises:

A water bath body, wherein one side of the water bath body is provided with a water replenishing mechanism for automatically replenishing water into the water bath body;

A stirring mechanism, the stirring mechanism is installed on the top of the water bath body, the stirring mechanism includes a support frame fixedly installed on the top side of the water bath body, a hydraulic cylinder fixedly arranged on the top side of the support frame, a stirring motor fixedly installed on the output end of the hydraulic cylinder, an I-shaped shaft arranged at the end of the output shaft of the stirring motor, a stirring shaft fixedly installed at the bottom end of the I-shaped shaft, a protective cover sleeved on the surface of the I-shaped shaft, a stirring sheet fixedly installed at the bottom end of the stirring shaft and a connecting plate arranged on the left side of the protective cover; a mixing shell, the mixing shell is arranged on the top side of the water bath body; a purification component, the purification component is arranged on the top side of the connecting plate; a quantitative mechanism, the quantitative mechanism is fixedly installed on the top side of the protective cover.

As a preferred solution of the water bath of the degradable composite barrier coating applied to paper-based materials according to the present invention, the water bath body includes a water bath shell, legs fixedly mounted on the bottom side surface of the water bath shell, a drain pipe fixedly mounted on the left side of the bottom end of the water bath shell, a support filter plate mounted on the inner wall of the water bath shell, and a control panel fixedly mounted on the front side surface of the water bath shell; a valve is installed on the top side of the end of the drain pipe; a mixing shell is provided on the top side of the support filter plate; the control panel is electrically connected to the water replenishment pump, the first water level sensor and the second water level sensor.

As a preferred solution of the water bath pot for the degradable composite barrier coating applied to paper-based materials of the present invention, the length of the stirring shaft is less than the depth of the inner cavity of the mixing shell, and stirring blades are symmetrically fixedly installed on the bottom end of the stirring shaft.

As a preferred solution of the water bath pot for the degradable composite barrier coating applied to the paper-based material described in the present invention, wherein: a slide groove (a) is opened on the inner wall on the left side of the support frame, a guide rod is fixedly connected to the inner wall of the slide groove (a), a slider is slidably sleeved on the surface of the guide rod, and the side surface of the slider is fixedly connected to the connecting plate.

As a preferred solution of the water bath pot for the degradable composite barrier coating applied to the paper-based material of the present invention, the front side cross-section of the I-shaped shaft is an I-shaped structure, a protective cover is rotatably sleeved on the surface of the I-shaped shaft, and the protective cover is sleeved on the top of the mixing shell.

As a preferred solution of the water bath of the degradable composite barrier coating applied to paper-based materials described in the present invention, the water replenishment mechanism includes a water replenishment tank, a water replenishment pump, a water replenishment pipe, a first water level sensor and a second water level sensor, the water replenishment tank is fixedly installed on the right side surface of the water bath shell, a water replenishment pump is fixedly installed on the inner wall of the bottom end of the water replenishment tank, the output end of the water replenishment pump is connected to the inner cavity of the water bath shell through the water replenishment pipe, the first water level sensor is installed on the inner wall of the water bath shell, and the top side of the first water level sensor is provided with a second water level sensor installed on the inner wall of the water bath shell.

As a preferred solution of the water bath pot for the degradable composite barrier coating applied to the paper-based material described in the present invention, wherein: the purification component includes a purification shell, the purification shell is fixedly mounted on the top side of the connecting plate, a partition is fixedly connected inside the purification shell, the purification shell is divided into an activated carbon particle placement chamber and a citric acid aqueous solution chamber by the partition, the top side of the activated carbon particle placement chamber is fixedly connected with a first discharge pipe and a first connecting pipe, the bottom side of the citric acid aqueous solution chamber is fixedly connected with a second discharge pipe and a second connecting pipe, the first connecting pipe and the second connecting pipe can be connected with an air outlet pipe, the air outlet pipe is connected with the output end of the air pump fixed on the connecting plate, and the input end of the air pump is connected with the mixing shell through the air pump.

As a preferred solution of the water bath pot for the degradable composite barrier coating applied to the paper-based material described in the present invention, wherein: a first drainage pipe fixedly connected to the purification shell is arranged on the positive side of the bottom end of the activated carbon particle placement cavity; a second drainage pipe fixedly connected to the purification shell is arranged on the positive side of the bottom end of the citric acid aqueous solution cavity; the bottom end of the first connecting pipe passes through the top side of the purification shell and is connected to the inner cavity at the bottom end of the activated carbon particle placement cavity; the bottom end of the second connecting pipe passes through the top side of the purification shell and is connected to the inner cavity at the bottom end of the citric acid aqueous solution cavity.

As a preferred solution of the water bath pot for the degradable composite barrier coating applied to the paper-based material according to the present invention, the quantitative mechanism includes a quantitative shell, scale lines, a feed pipe and a valve, the feed pipe is fixedly connected to the top side of the protective cover, the top end of the feed pipe is fixedly connected to the quantitative shell, the front side surface of the quantitative shell is provided with scale lines, and the feed pipe is installed with a valve.

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

The present invention is a degradable composite barrier coating applied to paper-based materials, a PVA-PHB composite material, which has ideal film-forming properties and adhesion. A large number of strong polar hydroxyl groups exist within and between molecules, which makes the molecular chains of the composite material stacked regularly, slows down the diffusion rate of gas in the film, and because of its high degree of cross-linking, prolongs the diffusion path, thereby improving the gas barrier properties of the packaging film.

When the water level is lower than the first water level sensor, the water supply pump is started, and the water supply pump injects the water in the water supply tank into the inner cavity of the water bath shell through the water supply pipe. When the water level reaches the second water level sensor, the water supply pump stops working to realize the automatic replenishment of water in the inner cavity of the water bath shell. During the PVA dissolution process, 20g PVA1799 is dissolved in a 100ml DMF mixed shell, and the hydraulic cylinder is started. The protective cover connected to the bottom of the hydraulic cylinder is adjusted to cover the top of the mixed shell. The temperature of the water bath is adjusted to 95°C. By starting the stirring motor, the stirring sheet is driven by the stirring shaft to fully stir the solution in the mixed shell to improve the dissolution stability;

When preparing 20% PVA aqueous solution, the air outlet pipe is connected to the second connecting pipe, and the odor gas dissolved in the mixing shell is extracted by a vacuum pump and injected into the citric acid aqueous solution cavity through the second connecting pipe. The odor is neutralized by the internal citric acid aqueous solution to ensure the surrounding air quality. In the subsequent mixing, the air outlet pipe is connected to the first connecting pipe, and the gas in the stirring process is adsorbed and purified by the activated carbon particles in the activated carbon particle placement cavity to improve the gas quality and meet the use requirements.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

FIG1 is a flow chart of the method for preparing the degradable composite barrier coating of the present invention.

FIG. 2 is a schematic diagram of the overall three-dimensional structure of a water bath of the degradable composite barrier coating applied to paper-based materials according to the present invention.

FIG3 is a schematic diagram of the overall front cross-sectional structure of a water bath of the degradable composite barrier coating applied to paper-based materials according to the present invention.

FIG. 4 is a top view schematic diagram of the connection between the heat dissipation cavity support frame and the slider of the water bath pot of the degradable composite barrier coating applied to the paper-based material of the present invention.

FIG. 5 is a schematic diagram of the purification component structure of the water bath of the degradable composite barrier coating applied to the paper-based material of the present invention.

FIG. 6 is a schematic diagram of the quantitative mechanism structure of the water bath pot of the degradable composite barrier coating applied to the paper-based material of the present invention.

FIG. 7 is a schematic diagram of the connection structure between the stirring shaft and the stirring plate of the water bath pot of the degradable composite barrier coating applied to the paper-based material of the present invention.

In the figure: 100, water bath body; 101, water bath shell; 102, legs; 103, filter support plate; 104, control panel; 105, drain pipe;

200, water replenishment mechanism; 201, water replenishment tank; 202, water replenishment pump; 203, water replenishment pipe; 204, first water level sensor; 205, second water level sensor;

300, stirring mechanism; 301, support frame; 301a, slideway; 302, hydraulic cylinder; 303, stirring motor; 304, I-axis; 305, stirring shaft; 306, stirring blade; 307, slider; 308, guide rod; 309, protective cover; 310, connecting plate;

400, purification component; 401, purification shell; 401a, activated carbon particle placement chamber; 401b, citric acid aqueous solution chamber; 402, partition; 403, first connecting pipe; 404, first discharge pipe; 405, second connecting pipe; 406, second discharge pipe; 407, air outlet pipe; 408, air pump; 409, air extraction pipe; 410, first liquid discharge pipe; 411, second liquid discharge pipe;

500, mixed shell;

600, quantitative mechanism; 601, quantitative shell; 602, scale line; 603, feed pipe; 604, valve.

DETAILED DESCRIPTION

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

Example

Referring to FIG. 1 , this embodiment provides a degradable composite barrier coating applied to a paper-based material. The preparation method of the degradable composite barrier coating comprises the following steps:

S1. Take 20g PVA1799 and dissolve it in 100ml DMF. After dissolution, place it in a 95°C water bath and stir until PVA is completely dissolved to obtain a 20% PVA aqueous solution;

S2. Add 0.2 g of preservative Nepal gold butyl ester to the PVA aqueous solution at room temperature, stir for 10 minutes, then add 0.2 ml of concentrated hydrochloric acid, stir for ten minutes, perform quality inspection, and discharge;

S3. Add 10 g PHB to the above solution, place it in a water bath at 80° C., add 3.27 g IPDI, and start stirring until the suspended matter in the solution is completely dissolved to obtain a PVA-PHB composite material.

There are three steps for gas to diffuse through the packaging film.

(1) The packaging film contacts the diffused gas molecules and adsorbs them, while the gas molecules dissolve on the film surface;

(2) Gas molecules gradually dissolve in the membrane. Under the influence of concentration difference, gas molecules diffuse from the side with high concentration to the side with low concentration.

(3) When the gas concentration in the membrane reaches saturation, gas molecules precipitate from the other side of the membrane; when the gas concentration inside the membrane and on both sides of the membrane is stable, gas diffusion is completed.

It can be seen that the PVA-PHB composite material has ideal film-forming and adhesion properties. There are a large number of strongly polar hydroxyl groups within and between its molecules, which make the molecular chains of the composite material stacked regularly, slow down the diffusion rate of gas in the film, and due to its high degree of cross-linking, extend the diffusion path, thereby improving the gas barrier properties of the packaging film.

PVA/PHB cross-linking mechanism

Example

1 to 7 , this embodiment is different from the first embodiment in that: this embodiment provides a water bath pot for a degradable composite barrier coating applied to a paper-based material, which includes a water bath pot body 100, a water replenishment mechanism 200 for automatically replenishing water in the pot body is provided on one side of the water bath pot body 100; a stirring mechanism 300, the stirring mechanism 300 is installed at the top of the water bath pot body 100, and the stirring mechanism 300 includes a support frame 301 fixedly installed on the top side of the water bath pot body 100, and the support frame 301 is fixedly arranged with the support frame A hydraulic cylinder 302 on the top side of 301, a stirring motor 303 fixedly mounted on the output end of the hydraulic cylinder 302, an I-shaped shaft 304 arranged at the end of the output shaft of the stirring motor 303, a stirring shaft 305 fixedly mounted at the bottom end of the I-shaped shaft 304, a protective cover 309 sleeved on the surface of the I-shaped shaft 304, a stirring blade 306 fixedly mounted on the bottom end of the stirring shaft 305 and a connecting plate 310 arranged on the left side of the protective cover 309; a mixing shell 500, the mixing shell 500 is arranged on the top side of the water bath pot body 100.

The water bath body 100 includes a water bath shell 101, a support leg 102 fixedly mounted on the bottom side surface of the water bath shell 101, a drain pipe 105 fixedly mounted on the left side of the bottom end of the water bath shell 101, a support filter plate 103 mounted on the inner wall of the water bath shell 101, and a control panel 104 fixedly mounted on the front side surface of the water bath shell 101;

A valve 604 is installed on the top side of the end of the drain pipe 105;

A mixing shell 500 is provided on the top side of the supporting filter plate 103 . The control panel 104 is electrically connected to the water replenishment pump 202 , the first water level sensor 204 and the second water level sensor 205 .

The length of the stirring shaft 305 is smaller than the depth of the inner cavity of the mixing shell 500 , and stirring blades 306 are symmetrically fixedly installed at the bottom end of the stirring shaft 305 .

A slide groove 301 a is provided on the inner wall of the left side of the support frame 301 , a guide rod 308 is fixedly connected to the inner wall of the slide groove 301 a , a slider 307 is slidably sleeved on the surface of the guide rod 308 , and the side surface of the slider 307 is fixedly connected to the connecting plate 310 .

The front side section of the I-shaped shaft 304 is an I-shaped structure, and a protective cover 309 is rotatably sleeved on the surface of the I-shaped shaft 304 , and the protective cover 309 is sleeved on the top of the mixing shell 500 .

Furthermore, the water replenishment mechanism 200 includes a water replenishment tank 201, a water replenishment pump 202, a water replenishment pipe 203, a first water level sensor 204 and a second water level sensor 205. The water replenishment tank 201 is fixedly installed on the right side surface of the water bath shell 101, and the water replenishment pump 202 is fixedly installed on the inner wall of the bottom end of the water replenishment tank 201. The output end of the water replenishment pump 202 is connected to the inner cavity of the water bath shell 101 through the water replenishment pipe 203. The first water level sensor 204 is installed on the inner wall of the water bath shell 101, and the top side of the first water level sensor 204 is provided with a second water level sensor 205 installed on the inner wall of the water bath shell 101.

Specifically, the quantitative mechanism 600 includes a quantitative shell 601, a scale line 602, a feed pipe 603 and a valve 604. The feed pipe 603 is fixedly connected to the top side of the protective cover 309. The top of the feed pipe 603 is fixedly connected to the quantitative shell 601. The scale line 602 is provided on the front side surface of the quantitative shell 601. The feed pipe 603 is installed with a valve 604, which is convenient for adding the liquid into the mixing shell 500 through the quantitative shell 601 after quantitative measurement.

Operation process: when the water level is lower than the first water level sensor 204, start the water replenishment pump 202, and the water replenishment pump 202 injects the water in the water replenishment tank 201 into the inner cavity of the water bath shell 101 through the water replenishment pipe 203. When the water level reaches the second water level sensor 205, the water replenishment pump 202 stops working to realize the automatic replenishment of water in the inner cavity of the water bath shell 101. During the PVA dissolution process, 20g PVA1799 is dissolved in 100ml of DMF in the mixing shell 500, and the hydraulic cylinder 302 is started. The protective cover 309 connected to the bottom of the hydraulic cylinder 302 is adjusted to cover the top of the mixing shell 500. The temperature of the water bath is adjusted to 95°C. By starting the stirring motor 303, the stirring sheet 306 is driven by the stirring shaft 305 to fully stir the solution in the mixing shell 500 to improve the dissolution stability.

Example

1-2 and 4, the embodiment is different from the above embodiment in that: the purification component 400 is arranged on the top side of the connecting plate 310; the quantitative mechanism 600 is fixedly installed on the top side of the protective cover 309, the purification component 400 includes a purification shell 401, the purification shell 401 is fixedly installed on the top side of the connecting plate 310, and a partition 402 is fixedly connected to the purification shell 401. The purification shell 401 is separated into an activated carbon particle placement chamber 401a and a citric acid aqueous solution chamber 401a by the partition 402. The liquid chamber 401b and the activated carbon particle placement chamber 401a are respectively fixedly connected with a first discharge pipe 404 and a first connecting pipe 403 on the top side, and the citric acid aqueous solution chamber 401b is respectively fixedly connected with a second discharge pipe 406 and a second connecting pipe 405 on the bottom side. The first connecting pipe 403 and the second connecting pipe 405 can both be connected with an air outlet pipe 407, and the air outlet pipe 407 is connected with the output end of the air pump 408 fixed on the connecting plate 310, and the input end of the air pump 408 is connected with the mixing shell 500 through the air pump 409;

The first drain pipe 410 fixedly connected to the purification shell 401 is disposed at the positive side of the bottom end of the activated carbon particle placement chamber 401a; the second drain pipe 411 fixedly connected to the purification shell 401 is disposed at the positive side of the bottom end of the citric acid aqueous solution chamber 401b;

The bottom end of the first connecting pipe 403 passes through the top side of the purification shell 401 and is connected to the bottom inner cavity of the activated carbon particle placement cavity 401a;

The bottom end of the second connecting pipe 405 passes through the top side of the purification shell 401 and is connected to the inner cavity at the bottom end of the citric acid aqueous solution chamber 401b.

During the operation, when preparing 20% PVA aqueous solution, the air outlet pipe 407 is connected to the second connecting pipe 405, and the odor gas dissolved in the mixing shell 500 is extracted through the vacuum pump 408, and injected into the citric acid aqueous solution chamber 401b through the second connecting pipe 405. The odor is neutralized by the internal citric acid aqueous solution to ensure the quality of the surrounding air. In the subsequent mixing, the air outlet pipe 407 is connected to the first connecting pipe 403, and the gas in the stirring process is adsorbed and purified by the activated carbon particles in the activated carbon particle placement chamber 401a, thereby improving the gas quality and meeting the use requirements.

Importantly, it should be noted that the construction and arrangement of the present application shown in a number of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, and parameter values (e.g., temperature, pressure, etc.), mounting arrangements, use of materials, color, changes in orientation, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, an element shown as integrally formed may be composed of multiple parts or elements, the position of the element may be inverted or otherwise changed, and the nature or number or position of the discrete element may be altered or changed. Therefore, all such modifications are intended to be included within the scope of the present invention. The order or sequence of any process or method steps may be changed or reordered according to an alternative embodiment. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and is not only structurally equivalent but also equivalent structure. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present invention. Therefore, the invention is not limited to a specific embodiment, but extends to several modifications still falling within the scope of the appended claims.

Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment may not be described (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those features that are not relevant to implementing the invention).

It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims (1)

1. A degradable composite barrier coating applied to a paper-based material, characterized in that the preparation method of the degradable composite barrier coating comprises the following steps: S1. Dissolve 20g PVA1799 in 100ml DMF, and place in a 95°C water bath and stir until PVA is completely dissolved to obtain a 20% PVA solution. S2. Add 0.2 g of Nepal gold butyl ester, a preservative, to the PVA solution at room temperature, stir for 10 min, then add 0.2 ml of concentrated hydrochloric acid, stir for ten minutes, perform quality inspection, and discharge; S3. Add 10 g PHB to the above solution, place it in a water bath at 80° C., add 3.27 g IPDI, and start stirring until the suspended matter in the solution is completely dissolved to obtain a PVA-PHB composite material.