KR101744395B1 - Process for preparation of the flexible substrate using a biodegradable starch - Google Patents
Process for preparation of the flexible substrate using a biodegradable starch Download PDFInfo
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- KR101744395B1 KR101744395B1 KR1020150076117A KR20150076117A KR101744395B1 KR 101744395 B1 KR101744395 B1 KR 101744395B1 KR 1020150076117 A KR1020150076117 A KR 1020150076117A KR 20150076117 A KR20150076117 A KR 20150076117A KR 101744395 B1 KR101744395 B1 KR 101744395B1
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
- C08J5/18—Manufacture of films or sheets
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/0008—Organic ingredients according to more than one of the "one dot" groups of C08K5/01 - C08K5/59
- C08K5/0025—Crosslinking or vulcanising agents; including accelerators
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L29/00—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal or ketal radical; Compositions of hydrolysed polymers of esters of unsaturated alcohols with saturated carboxylic acids; Compositions of derivatives of such polymers
- C08L29/02—Homopolymers or copolymers of unsaturated alcohols
- C08L29/04—Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L3/00—Compositions of starch, amylose or amylopectin or of their derivatives or degradation products
- C08L3/02—Starch; Degradation products thereof, e.g. dextrin
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2201/00—Properties
- C08L2201/10—Transparent films; Clear coatings; Transparent materials
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- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
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Abstract
The present invention relates to a method for producing a large-area flexible electronic device substrate by using a starch having a high biodegradation property as a raw material at a low cost and simple process, wherein starch is mixed and stirred in distilled water, and an organic binder and a cross- And gelling the mixed solution by mixing to form a film. The present invention also provides a method of manufacturing a transparent substrate for a flexible electronic device.
Description
BACKGROUND OF THE
BACKGROUND ART [0002] Recent researches on transparent and flexible plastic substrates that can replace existing organic substrates such as organic light emitting display devices and electronic paper as materials for electronic devices have been actively conducted.
Substituting a glass substrate with a plastic substrate as a base material makes it possible to reduce the overall weight of the electronic device, to impart flexibility to the device, to be resistant to impact, and to be manufactured in a continuous process. It has a big advantage.
Currently, PET (poly (ethylene terephthalate)), PEN (poly (ethylene naphthalate)), PC (polycarbonate), PES (polyester)
Such synthetic plastics have advantages such as strength, transparency, and chemical resistance, but are not decomposed when used after disposal, resulting in extreme environmental pollution, causing serious social problems.
Alternatively, the biodegradable resin may be a starch-based biodegradable plastic prepared by mixing starch, which is a non-toxic natural substance, with a universal plastic or a biodegradable plastic, And polylactide, epsilon-caprolactone, and other diol diacids-based aliphatic polyester-based biodegradable plastics synthesized through a ring opening reaction from lactide to a chemical catalytic enzyme.
Biodegradable resin is one of two kinds of high quality, but high in price and low in price but not excellent in quality. The polyester biodegradable resin belongs to the former, and the starch-type biodegradable resin belongs to the latter.
In the case of the starch-based biodegradable resin, the biodegradability of the biodegradable plastic is the most excellent, and the price is very low compared with the other raw materials, and the biodegradable flexible electronic device using starch Research on substrate manufacturing technology is actively under way.
However, biodegradable plastics using starch are relatively inexpensive and have excellent decomposability, but their use as a substrate for flexible electronic devices has been limited due to poor processability, tensile strength and transparency.
The present invention provides a plastic substrate having biodegradability as a plastic substrate for flexible electronic devices using starch as a raw material having biodegradability and a method for producing the plastic substrate.
More specifically, it is an object of the present invention to provide a method for producing a flexible electronic device substrate having improved tensile strength and transparency by adding at least an organic binder and a crosslinking agent to starch as a biodegradable raw material.
A method for producing a transparent substrate for a flexible electronic device according to the present invention relates to a method for producing a substrate for a large-area flexible electronic device using a starch having a high biodegradation property as a raw material at low cost and simple process. The starch is mixed with distilled water, And further mixing an organic binder and a cross-linking agent in the mixed solution to gel the mixed solution to form a film.
Mixing 0.1 to 0.3 parts by weight of starch with 100 parts by weight of distilled water and stirring the mixture; mixing and mixing 0.2 to 0.6 parts by weight of an organic binder with respect to 100 parts by weight of the starch, and stirring the starch; A step of heating the mixture solution mixed with the organic binder at 80 DEG C while stirring to induce a gel; cooling the gelled solution to remove bubbles; and molding the bubbled solution into a film shape And a method of manufacturing a transparent substrate for a biodegradable flexible electronic device.
Wherein the organic binder is a water-soluble polymer comprising polyvinyl alcohol having an average molecular weight of 2000 to 90000.
When the organic binder is mixed, the crosslinking agent is mixed with 1 to 10 parts by weight based on 100 parts by weight of polyvinyl alcohol. The crosslinking agent may be selected from among PMMA (poly (methylmethacrylate)) and PAFA (poly (alkyl a-fluoroacrylate)), preferably PAFA.
Specifically, the crosslinking agent is selected from the group consisting of poly (methyl α-fluoroacrylate) (PMFA), poly (ethyl α-fluoroacrylate) (PEFA), poly (propyl α-fluoroacrylate) And one or more of them are selected.
The bubbles may be removed by using a defoaming agent or the like, or may be removed from the vacuum desiccator. Preferably, a vacuum decompressor without additive is used.
The transparent substrate produced by the method of the present invention comprises 0.2 to 0.6 parts by weight of polyvinyl alcohol relative to 100 parts by weight of starch and 1 to 10 parts by weight of PMFA based on 100 parts by weight of polyvinyl alcohol.
Since the plastic substrate for flexible electronic devices is manufactured using starch which is a biodegradable raw material, when the device is discarded after use, it has a feature of minimizing environmental pollution due to biodegradation characteristics of the substrate.
In addition, since the raw material starch itself is inexpensive and the manufacturing method of the present invention is simplified, it has high price competitiveness and is economically advantageous.
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic view showing a method of manufacturing a transparent substrate for a flexible electronic device according to the present invention.
2 is a photograph showing an SEM (scanning electron microscope) image (a) and an AFM (atomic force microscope) image (b) of the surface of a transparent substrate prepared according to Example 1. Fig.
3 is a photograph of the result of bending strength of a transparent substrate prepared according to Example 1. Fig.
4 is a graph showing the results of the tensile strength (a) of the transparent substrate and the tensile strength (b) of the transparent substrate according to the content of the crosslinking agent in the minimum polyvinyl alcohol without the crosslinking agent and according to the content of the polyvinyl alcohol.
The present invention relates to a method for producing a transparent substrate for flexible electronic devices by mixing an organic binder as a binder of starch and a crosslinking agent for increasing the strength of a final substrate, The optimum ingredients for the purpose of minimizing additives and the like were selected as follows.
Starch is one of the important storage materials in plant seeds, roots, stem, alfalfa, and fruit, and is widely found in plants with chlorophyll as a nutrient source of carbohydrates in higher animals.
This starch is not a single substance but a mixture of linear polymer amylose and branched polymer amylopectin. The ratio is generally constant depending on the type of starch.
Generally, starch contains 20-25% amylose and 75-80% amylopectin. amylose forms a hard and opaque gel phase when dispersed, and amylopectin has a limited ability to hydrogen bond, so that it is relatively transparent and flexible in its dispersibility.
When the starch is dispersed in distilled water, it is preferable to select an appropriate amount in consideration of the density of the starch, the processability in forming the final film, the characteristics of the substrate, and the like.
When the amount of the gel is more than 0.3 parts by weight based on 100 parts by weight of distilled water, the viscosity of the gel is high during the final gelation, resulting in poor processability. When the amount is less than 0.1 part by weight, the viscosity of the gel is too low, The commerciality as a substrate is deteriorated.
Therefore, it is preferable that 0.1 to 0.3 parts by weight of starch is mixed with 100 parts by weight of distilled water and dispersed.
When only starch was used as a substrate material, polyvinyl alcohol was used as a binder to compensate for the durability against bending.
Polyvinyl alcohol is water soluble in vinyl polymer series and does not dissolve in organic solvent. However, polyvinyl alcohol has excellent adhesion to materials having hydrophilic surface such as oil, grease, and cellulose, and is currently used as a binder in various fields.
Accordingly, in the present invention, a water-soluble polymer containing polyvinyl alcohol is used as a binder in the production of a transparent substrate using starch, and in this case, adding a water-soluble polymer containing polyvinyl alcohol in a minimum amount in order to improve biodegradability desirable.
When the polyvinyl alcohol is added in an amount of 0.2 or less based on 100 parts by weight of the starch, it may cause cracking and tensile strength reduction on the surface of the film during formation of the final film. Therefore, the polyvinyl alcohol is preferably added in an amount of 0.2 or more, By weight or less. When 0.6 parts by weight or more is added, the transparency of the substrate is lowered due to haze of the film.
It is preferable to add a crosslinking agent in order to increase the tensile strength and solvent stability of the transparent substrate. It is also preferable to add the crosslinking agent in a minimum amount in order to improve the biodegradability and transparency of the substrate.
The crosslinking agent may be selected from among PMMA (poly (methylmethacrylate)) and PMFA (poly (alkyl a-fluoroacrylate)), but in the case of PAFA substituted with fluorine in the polymer chain, The PMFA is more preferable in that mechanical properties and water absorption characteristics are increased by the attractive force in the molecule and the physical properties such as compression and flexural strength and flexural modulus have better properties than PMMA.
More specific crosslinking agents include one of poly (methyl α-fluoroacrylate) (PMFA), poly (ethyl α-fluoroacrylate) (PEFA), poly (propyl α-fluoroacrylate) Or more is selected.
When the crosslinking agent is added in an amount of 1 part by weight or less based on 100 parts by weight of polyvinyl alcohol, the film tensile strength is reduced when the final film is formed. Therefore, the crosslinking agent is preferably added in an amount of 1 part by weight or more, Subparts are sufficient. When it is added in an amount of 10 parts by weight or more, haze of the film is generated and transparency is lowered. More preferably 3 to 5 parts by weight of a crosslinking agent relative to 100 parts by weight of polyvinyl alcohol.
In the present invention, an organic binder and a cross-linking agent are further mixed with the starch-dispersed mixed solution and then gelled to form a film. Bubbles of the mixed solution must be removed before the film is formed.
The bubble removal can be removed by adding a defoaming agent or the like, or physically removed from the reduced pressure desiccator. Preferably, the vacuum desiccator is used which does not add any additive to the mixed solution.
As a method for forming a film using the above mixed solution, a transparent substrate obtained by solution casting a glass plate as a molding substrate at a constant speed, drying it at room temperature for a certain period of time, and then removing the film formed at room temperature from the molding substrate. The transparent substrate according to the present invention can also be obtained through an extrusion molding method.
The finally completed transparent substrate can be cut and used according to the application.
Hereinafter, the present invention will be described in detail with reference to preferred embodiments. However, the embodiments are intended to further illustrate the present invention, and the scope of the present invention is not limited thereto, and various modifications are possible without departing from the technical idea of the present invention.
≪ Transparent substrate fabrication and analysis method >
As shown in FIG. 1, a mixed solution prepared by mixing starch and an organic binder was heated at 80 ° C to induce gelation, cooled, and then treated in a vacuum desiccator for 5 hours to completely remove air bubbles. Solution Casting After forming the film, the film was dried at room temperature for 7 days, and then the film was peeled off from the molding substrate to prepare a transparent substrate for flexible electronic devices.
Optical microscopy (OM) and Scanning Electron Microscopy (SEM) were used to analyze the surface of transparent substrates for flexible electronic devices. For mechanical properties, 1000 bending tests and tensile strengths were measured.
≪ Example 1 >
In Example 1, 6 g of starch was mixed and dispersed in 350 ml of distilled water, 30 mg of polyvinyl alcohol and 2.5 mg of PMFA as a crosslinking agent were added dropwise, and the mixture was stirred at 80 ° C to prepare a mixed solution containing gelled starch.
After cooling the gelled mixed solution, the bubbles were completely removed in a vacuum desiccator. The mixed solution from which air bubbles were removed was cast on a glass plate substrate, dried at room temperature for 7 days, and then peeled off from the substrate to obtain a transparent substrate for a biodegradable flexible electronic device containing starch.
≪ Example 2 >
A transparent substrate was prepared in the same manner as in Example 1 except that 0.5 parts by weight, 1.0 part by weight, 2.0 parts by weight, 3.0 parts by weight and 5.0 parts by weight of PMFA as a crosslinking agent were mixed with 100 parts by weight of polyvinyl alcohol, .
≪ Comparative Example 1 &
In Comparative Example 1, a transparent substrate for biodegradable flexible electronic devices containing starch was prepared in the same manner as in Example 1 except that no crosslinking agent was added.
≪ Comparative Example 2 &
A transparent substrate was prepared in the same manner as in Comparative Example 1 except that 0.5 parts by weight, 1.0 part by weight, 2.0 parts by weight, 3.0 parts by weight and 5.0 parts by weight of polyvinyl alcohol were mixed with respect to the starch.
≪ Comparative Example 3 &
In Comparative Example 2, a transparent substrate for biodegradable flexible electronic devices containing starch was prepared in the same manner as in Example 1 except that PMMA was used as a crosslinking agent.
≪ Property evaluation result >
As a result of analyzing the surface of the transparent film produced according to Example 1, it can be seen that small holes having a size of several tens to several hundreds of nm are seen as shown in FIG. 2, but the roughness of the surface is not large, and the bending strength is also shown in FIG. As a result, it can be seen that it can be used as a transparent substrate for flexible electronic devices.
4 (a) shows the result of tensile strength of a transparent substrate prepared by changing only the content of polyvinyl alcohol (PVA) without a crosslinking agent, and Fig. 4 ) Shows the tensile strength of a transparent substrate prepared by varying the content of crosslinking agent relative to polyvinyl alcohol in a mixed solution containing 0.5 part by weight of polyvinyl alcohol relative to 100 parts by weight of starch.
The tensile strength (a) of the polyvinyl alcohol according to the concentration without adding the cross-linking agent of FIG. 4 is easily broken according to the length of the stretching at a low strength. However, when the crosslinking agent is added, it can be confirmed that the tensile strength (b) stays at a strong force for a relatively long time. When the crosslinking agent was contained in an amount of 5 parts by weight with respect to 100 parts by weight of the polyvinyl alcohol, the best mechanical properties were exhibited.
As described above, it was confirmed that the mechanical properties were increased according to the content of polyvinyl alcohol. In order to maximize the biodegradability, it is preferable to add the minimum amount, preferably 0.2 to 0.6 part by weight relative to 100 parts by weight of the starch, , Even when 1 to 10 parts by weight of the polyvinyl alcohol is added to 100 parts by weight of the polyvinyl alcohol, sufficient mechanical properties can be obtained, and thus it can be used as a transparent substrate for flexible electronic devices.
Claims (8)
Mixing and stirring 0.2 to 10 parts by weight of an organic binder with respect to 100 parts by weight of starch,
Heating the mixed solution obtained by mixing the starch and the organic binder with stirring at 80 DEG C to induce gelation,
Cooling the gelled solution to remove air bubbles,
Forming the solution from which the bubbles have been removed into a film shape,
Wherein the poly (alkyl alpha-fluoroacrylate) (PAFA) is added in an amount of 1 to 10 parts by weight based on 100 parts by weight of the organic binder when the organic binder is mixed.
Wherein the organic binder is a water-soluble polymer containing polyvinyl alcohol.
Wherein the polyvinyl alcohol has an average molecular weight of 2,000 to 900,000.
The poly (alkyl α-fluoroacrylate) (PAFA) may be selected from the group consisting of poly (methyl α-fluoroacrylate) (PMFA), poly (ethyl α-fluoroacrylate) fluoroacrylate (PBFA) is selected as a transparent conductive material for a flexible electronic device
Wherein the step of removing the bubbles is carried out using a vacuum desiccator and a defoaming agent.
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| KR1020150076117A KR101744395B1 (en) | 2015-05-29 | 2015-05-29 | Process for preparation of the flexible substrate using a biodegradable starch |
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| KR1020150076117A KR101744395B1 (en) | 2015-05-29 | 2015-05-29 | Process for preparation of the flexible substrate using a biodegradable starch |
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| KR20160141238A KR20160141238A (en) | 2016-12-08 |
| KR101744395B1 true KR101744395B1 (en) | 2017-06-09 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20190142628A (en) | 2018-06-18 | 2019-12-27 | 한국생산기술연구원 | Natural disposable electronic circuit element and manufacturing method thereof |
| KR20200054016A (en) | 2018-11-09 | 2020-05-19 | 한국생산기술연구원 | Method for manufacturing disposable printed circuit board and the printed circuit board prepared using the same |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001352176A (en) * | 2000-06-05 | 2001-12-21 | Fuji Xerox Co Ltd | Multilayer printed wiring board and manufacturing method of multilayer printed wiring board |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20010100067A (en) | 2001-08-30 | 2001-11-14 | 김권 | Biodegradable resin composition combined with starch |
| KR101236085B1 (en) | 2007-06-01 | 2013-02-21 | 주식회사 엘지화학 | Method for manufacturing transparent plastic film |
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Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001352176A (en) * | 2000-06-05 | 2001-12-21 | Fuji Xerox Co Ltd | Multilayer printed wiring board and manufacturing method of multilayer printed wiring board |
Non-Patent Citations (1)
| Title |
|---|
| 윤연흠 외 1명, "Starch와 PVA를 이용한 생분해성 필름의 제조와 물리적 특성", J. of Advanced Engineering anf Technology, Vol. 1, No. 1, pp.173-177. (2008)* |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20190142628A (en) | 2018-06-18 | 2019-12-27 | 한국생산기술연구원 | Natural disposable electronic circuit element and manufacturing method thereof |
| KR102180112B1 (en) | 2018-06-18 | 2020-11-18 | 한국생산기술연구원 | Natural disposable electronic circuit element and manufacturing method thereof |
| KR20200054016A (en) | 2018-11-09 | 2020-05-19 | 한국생산기술연구원 | Method for manufacturing disposable printed circuit board and the printed circuit board prepared using the same |
| KR102117861B1 (en) * | 2018-11-09 | 2020-06-02 | 한국생산기술연구원 | Method for manufacturing disposable printed circuit board and the printed circuit board prepared using the same |
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| KR20160141238A (en) | 2016-12-08 |
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