JP2017095545A - Process for preparing biodegradable or biocompostable or biodigestible plastic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for preparing a biodegradable or biocompostable or biodigestible plastic.SOLUTION: Provided is a method for preparing a biodegradable or biocompostible or biodigestable PEPlene polymer including the following steps of: a step of mixing at least one kind of peptide, at least one kind of protein and enzyme; a step of adding a fermentation agent; and a step of mixing at least one polymer in the presence of an addition agent to generate a PEPlene polymer material.SELECTED DRAWING: Figure 1

Description

  The present invention relates to biodegradable, biopostable, biodigestible plastics and methods for their preparation, and more particularly to a process for preparing biodegradable or biopostable or biodigestible plastics.

Plastics such as polyethylene and polypropylene are made from petroleum.
The decomposition of these plastics takes many years in the natural environment, and thus pollutes water, soil and air.

Synthetic polymers produce different rates and different degrees of environmental degradation due to their polymer properties and the environment in which they exist.
This kind of decomposition occurs by catalytic reaction of mechanical force such as light, heat, air, water, microorganisms, wind, rain, traffic.
Polymers usually change from hydrophobic to hydrophilic materials due to additives, modification of the polymer backbone, introduction of functional groups, or mixing of suitable fillers, so that their stability and / or Enhanced degradation.
However, many of these degradation techniques generate harmful attributes for polymer products.

Synthetic polymers or plastics based on petroleum have excellent physical properties, light weight, and high cost performance, so that problems and limitations due to the use of natural materials can be overcome.
Plastic materials are one of the characteristics of modern science, and the development of various hydrophilic polymers, especially hydrophilic plastics, has already been demonstrated.
However, as pollution problems caused by large quantities of plastic products worldwide become more serious, various countermeasures have been enacted around the world.
Moreover, solving the pollution caused by plastic waste is a challenging agenda.

Recycling, incineration, and landfill have been the main means of solving the environmental pollution problems caused by various solid wastes including plastics.
However, the essential problem is that the environmental pollution problem cannot be thoroughly solved even by waste landfilling and recycling.

Thus, recently, the development of biodegradable and / or bio-possible plastics that naturally degrade at the end of the life cycle has been advancing great interest and research.
The above technology can be applied to the field of degradable plastics for photodegradation, oxidative degradation, oxidative biodegradation, biodegradability, bio-photometathesis, and recently optical and / or oxygen groups and / or Or it was divided into the combination of biodegradable plastic compounding technology.

Various biodegradable plastics have already been developed.
For example, a microbial-forming polymer is PHB (poly beta-hydroxybutyric acid), which is a biochemical polymer produced using microorganisms, or a daily polymer that includes a chitin or starch polymer.
In the present specification, starch is taken up in order to ameliorate the problems of various polymer additives related to the technology of the present invention.

G. J. et al. L. Griffin, U.S. Patent No. 5,677,077 discloses a preparation method for improving biodegradable thin films.
The above method treats the starch surface with a silane coupling agent, thereby forming hydrophobicity on the surface.
However, it can only increase the strength of a small amount of physical interaction between the matrix resin and starch, and cannot solve the problem of degrading its physical performance when the film is bonded to starch.

US Department of Agriculture (USDA) H. Patent Document 2 and Patent Document 3 filed by Otey et al. Disclose a method for preparing a biodegradable thin film by adding α-starch to an ethylene-acrylic acid copolymer.
However, the physical performance of a thin film produced from an ethylene-acrylic acid copolymer is inferior and expensive, and is difficult to spread in large quantities.

  Patent Document 4 and Patent Document 5 filed by Seonil Glucose of Korea have improved the physical interaction strength between matrix resin and starch by improving the hydrophobicity of starch or improving the hydrophilicity of matrix resin. A method for strengthening and increasing the compatibility of matrix resin and starch is disclosed.

U.S. Patent No. 6,057,031 discloses photodegradable and biodegradable polyethylene.
It produces a terpolymer with better photodegradability than the copolymer due to the co-processed ethylene and 2-methylene-1,3-dioxepane (MDOP).
This is because the carbonyl added to the polymer is broken by absorbing light (sunlight or ultraviolet rays).
The terpolymer has both photodegradability and biodegradability because the ester and carbonyl are functionalized together.

  Patent Document 7 discloses a biodegradable polyethylene composition that forms chemical bonding with starch and a method for preparing the same.

Therefore, it is necessary to provide peptide-polyethylene having high production efficiency.
In the present invention, it is called PEPrene.
It has good biodegradability or biopostable or biodigestibility in the environment.

U.S. Pat. No. 4,021,388 U.S. Pat. No. 4,133,784 U.S. Pat. No. 4,337,181 Korean patent 90-6336 specification Korean Patent No. 91-8553 Specification US Pat. No. 5,281,681A US Pat. No. 5,461,94A

  The process for preparing biodegradable or biopostable or biodigestible plastics according to the invention provides a biodegradable or biopostable or biodigestible plastic or polymer product.

Super bags, agricultural cover films, packaging films, etc. are all biodegradable, biocomposable or biodigestible by mixing biodegradable or biopostable or biodigestible additives during polymer processing. With the characteristics of
Thereby, it replaces with the plastics based on general petroleum.
Therefore, a plastic formulation is developed by mixing edible daily peptides, enzymes or proteins.
As a result, petroleum-based polymers that have not been biodegradable, that is, polyolefins such as polyethylene, polypropylene, and products of different grades become biodegradable, biocomposable or biodigestible polyolefin polymers.

In the present invention, a biodegradable or biocompatible or biodigestible thin film is prepared by chemical bonding using a peptide, enzyme or protein, other additives, and a polyethylene chain.
Polyolefin is generally applied and is a polymer that is widely used as a preparation method.
Processing techniques can be applied to other polyolefins such as polypropylene as well.

It is an environmental biodegradation state of a PEPrene thin film. The PEPrene thin film is in a state of biodegradation through 150 days of environmental soil. Peptides, enzymes or proteins mixed in a PEPrene masterbatch as shown by FTIR test. A peptide, enzyme, or protein mixed in a PEPrene thin film indicated by FTIR inspection. The percentage of biodegradation of PEPrene.

(One embodiment)
The present invention discloses a biodegradable, bio-postable, biodigestible plastic and method for its preparation.
The compositions and methods of preparation thereof provided by the present invention accelerate the biodegradability or biopostability or biodigestibility of PEPrene materials.

The method of preparing the composition includes at least one peptide bond, at least one protein and enzyme, and a fermenting agent.
Next, in the presence of a preferred additive, when the temperature condition is 45-300 ° C., at least one polymer is mixed to maintain the necessary catalytic reaction performance and the essence of the peptide, enzyme or protein.
The composition produced in this manner can be used directly or contained within a polymer to constitute a coating composition or coating solution.

The compositions of the various embodiments are described below.
Peptide-cellulose, papaya enzyme. However, it is not limited to the embodiment described in the text.
Protein or enzyme-milk, vegetable (soybean, okra), but not limited to the embodiments described herein.
Fermentant-carboxymethylcellulose, hydrolyzed mutton fat. However, it is not limited to the embodiment described in the text.
Polymer-polyethylene is at least one linear low density polyethylene (LLDPE), high density polyethylene (HDPE), low density polyethylene (LDPE), medium density polyethylene, ethylene vinyl acetate (EVA) and ethylene butyl acrylate (EBA). And any combination thereof.
Additives-citric acid, lactobacillus, hydrolyzed mutton fat, yeast and any combination thereof improve the biodegradability or biopostability or biodigestibility of the polymeric material.

The composition of the present invention is a food ingredient of a natural ingredient and can contain other carbohydrate compounds such as lactose and starch.
The present invention simplifies the process of preparing the composition and reduces production costs.
The strength of the physical interaction between the matrix resin and the peptide or enzyme or protein and the above-mentioned additive is increased, thus solving the problem of thin film property degradation.
In addition, another specific embodiment, a biodegradable or biopostable or biodigestible polyethylene composition and starch are interconnected by chemical bonding.

  As shown in FIG. 1, the PEPrene composition has a molecular weight of at least about 7000 and has good biodegradability or biopostability or biodigestibility.

As shown in FIG. 3 and FIG. 4, in a plastic polymer, peptides or enzymes or protein groups (carboxyl, etc.) are randomly distributed along the polyethylene polymer backbone based on functional groups of different concentrations of x, y, and z in a space integer. Or evenly distributed in the polymer.
The compression temperature of the blend of plastic compositions is 100-350 ° C.
Thus, in the compression process, the composition penetrates or injects the cell or molecular structure of the polymer when the polymer is in a pre-melted state.

Plastic products obtained by the process of the present invention include secondary packaging or plastic films, vest bags, trash liners, trash bags, agricultural cover films and many other types of thin films.
Currently blends of compositions are applied to the polymer.
Examples include 3D printing, fiber spinning, non-woven materials that are injection molded, and melt spinning processing techniques, but these are only examples.

The biodegradable mechanism involves several steps:
Treatment: Peptide, enzyme or protein is introduced to make the polymer chain hydrophilic. In the process of squeezing the peptide or enzyme or protein and penetrating the polymer, the polymer is in a pre-molten state and thus the polymer formulation is hydrophilic.
Pyrolysis: Polymers with hydrophilic properties are further processed into polymer films. Based on laboratory temperature conditions, environmental humidity, and the reaction of light and oxygen, thermal decomposition occurs or decomposes into smaller fragments.
Soil treatment: After pyrolysis (whether under laboratory conditions or in the natural environment), the peptides, enzymes or proteins present in the composition of the present invention are hydrophilic, so they can easily attract soil microorganisms and polymer Will be attacked. Due to the hydrophilic nature of the composition and / or the moisture in the soil (eg, 58% moisture), the polymer formulation contains inherent moisture, causing the polymer chain to separate or weaken into a molecular state. Thus, through the process of natural composting, the depolymerized product therein provides nutrients for the microorganisms in the soil, and the surplus product becomes a raw material.
Degradation: The polymer becomes carbon dioxide and water, which are the final metabolites of biodegradation, due to the metabolic action of microorganisms.

In one specific embodiment, the enzyme composition of the present invention is mixed with a kind of powdery copolymer, that is, linear low density polyethylene (LLDPE).
Polyethylene is used for the production of thin films for secondary packaging such as vest bags, trash liners, trash bags, agricultural cover films and the like.
In order to increase the elasticity and expandability of the thin film, it is necessary to mix a linear low density polyethylene (LLDPE) copolymer.
Peptides or enzymes or proteins present in polyethylene and other additives attract microorganisms in the soil and cause the action of compost material.
The remainder is biomass, water and carbon dioxide.
The PEPrene polymer biodegradable residue of the present invention is carbon dioxide and water.

Other biodegradable or biological refined products are gases (such as methane), ketones (such as acetone), and alcohols (such as methanol, ethanol, propanol, and butanol).
Products such as methane and ethanol are known energy sources, and these or other products expected to be obtained may be obtained and can be used further as energy sources and the like.

The advantages of the present invention are that the polymer product produced by the present invention retains the required mechanical performance and shelf life, and the polymer can be recycled in the same manner as a non-biodegradable polymer such as polyethylene.
Unlike spontaneous polymer degradation with photo-oxidation or oxidative degradation agents, it does not reduce the shelf life of polymer products and is exposed to the microbial environment in the course of enzymatic biodegradability or bio-postable or biodigestible processes. All you need to do is then follow the life cycle.

In the present invention, a PEPrene thin film is prepared by using a peptide, enzyme, or protein composition and directly dispersing or including it.
Furthermore, based on ASTM D5988, ISO14855, ISO17556 and EN13432 or ASTM D6400 (equivalent standard in other countries) test standards, the biodegradability and ecotoxicity of these thin films and biodegradability including soil germination ability were successfully tested. did.
For example, EN rules stipulate that cellulosic products achieve over 90% degradation within 180 days.

As shown in FIG. 1 and FIG. 2, the product of the present invention starts to decompose from 90 days based on the composting test conditions.
The degradation rate is usually affected by environmental microbial conditions, peptide or enzyme or protein composition amount and product thickness.
For example, the extrudable film thickness of degradable products prepared according to the present invention has reached 5-50 microns.
Thus, another advantage of the present invention is that the composition is natural and includes provisions for food grade raw materials, national plastic materials or products, does not contain toxic substances after degradation, and / or heavy metal content is within the limits of regulation. Is within.

The product of the present invention is also recyclable based on ASTM D7209 and EN15347 standards.
The product of the present invention is also compostable based on the EN13432 standard.
Based on ASTM D5988, ISO14855, ISO17556 standards and EN13432 or ASTM D6400 (equivalent standard in other countries) test standards, this product is a biodegradable plastic (see FIG. 5).
In addition, the present invention is based on the test of US FDA 177.1520 and meets the food contact safety regulations.

Another advantage of the present invention is that the materials prepared according to the present invention are readily biodegradable under suitable environmental conditions.
The PEPrene thin films of the present invention are all very stable prior to treatment, buried in soil, composted, landfilled, using biodegradation equipment or similar equipment, and under anaerobic conditions.
The material is a microbial group formed by colonies present in the composition of the present invention and effective microorganisms in the soil are metabolic products.
Polyolefins such as polyethylene in the composition of the present invention are completely biodegraded and biocomposted under aerobic conditions, with the thin film being attacked by oxidizing microorganisms.
The present invention is easily modified, adjusted and altered by a technician skilled in this area.

  The embodiments of the present invention described above do not limit the present invention, and therefore the scope protected by the present invention is based on the claims described below.

Claims (9)

A process for preparing a biodegradable or biocompatible or biodigestible plastic, comprising the following steps:
Mixing at least one peptide and at least one protein and enzyme,
Add fermenting agent,
A process for preparing a biodegradable or biocompatible or biodigestible plastic characterized in that in the presence of an additive, at least one polymer is mixed to produce said plastic. The best temperature for the mixing conditions is 45-300 ° C.
2. The biodegradable or biopostable or biodigestible plastic according to claim 1, wherein the necessary catalytic reaction performance and the essence of the peptide, enzyme or protein in the solid or liquid state are maintained. Process.   The process for preparing a biodegradable or biocompatible or biodigestible plastic according to claim 1 or 2, wherein the peptide is cellulose or papaya enzyme.   4. The biodegradable or bio-postable or biodigestible plastic according to any one of claims 1 to 3, wherein the peptide, enzyme or protein is a vegetable such as milk, soybean or okra. Process.   The process for preparing a biodegradable, biocompatible or biodigestible plastic according to any one of claims 1 to 4, wherein the fermenting agent is carboxymethylcellulose.   The polymer is polyethylene or the like, linear low density polyethylene (LLDPE), high density polyethylene (HDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), ethylene vinyl acetate (EVA) and ethylene butyl acrylate. A process for preparing a biodegradable or biocompatible or biodigestible plastic according to any one of claims 1 to 5, characterized in that it is (EBA) and any combination thereof.   7. The biodegradable or bio-possible or biological organism according to any one of claims 1 to 6, wherein the additive is citric acid, lactobacillus, hydrolyzed mutton fat, yeast and any combination thereof. The process of preparing digestible plastics.   8. The compression temperature of the plastic blend is 350 ° C. to form blown or injection molded products, melt spinning, 3D printing, and many other products. The process of preparing biodegradable or bio-postable or biodigestible plastics.   9. The plastic product produced by the process includes secondary packaging or plastic film, vest bag, trash liner, trash bag, agricultural cover film, polymer fiber, non-woven material. A process for preparing a biodegradable or bio-possible or bio-digestible plastic according to any one item.

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