KR102377749B1 - A biodegradable polymer complex using wood flour and a method for manufacturing the same - Google Patents

Abstract

The present invention relates to a biodegradable polymer composite using wood flour and a manufacturing method thereof, and more specifically, to a biodegradable polymer composite using wood flour and a manufacturing method thereof which comprises: a step (a) of first drying the wood powder; a step (b) of mixing the first dried wood powder and stearate to coat a surface of the wood powder; a step (c) of mixing the coated wood powder, biodegradable polymer, inorganic filler, starch, lubricant, unsaturated fatty acid, organic acid, and peroxide, and then secondary drying the mixture to prepare a composition; and a step (d) of extruding the composition to prepare a biodegradable polymer composite.

Description

A biodegradable polymer complex using wood flour and a method for manufacturing the same

The present invention relates to a biodegradable polymer composite using wood flour and a method for producing the same, and more particularly, to: (a) primary drying of wood flour; (b) coating the surface of the wood powder by mixing the first dried wood flour and stearate; (c) preparing a composition by mixing the coated wood flour, biodegradable polymer, inorganic filler, starch, lubricant, unsaturated fatty acid, organic acid and peroxide, followed by secondary drying; and (d) extruding the composition to prepare a biodegradable polymer composite. It relates to a biodegradable polymer composite using wood flour and a method for producing the same.

Existing petroleum-based plastic materials require a long time to decompose naturally, and serious environmental pollution occurs in the process of processing them. there is.

These existing plastic materials are being processed through landfilling, incineration, recycling, etc. However, as environmental problems have recently emerged, many countries are obliged to use bioplastics.

In this regard, research on bioplastics that can be completely decomposed into methane gas and the like is being conducted in various ways.

Bioplastics are largely divided into biodegradable plastics, which decompose within 6 months compared to cellulose, and bio-based plastics, which have a biodegradation period of more than 6 months but overcome the disadvantages of existing biodegradable plastics and emphasize carbon dioxide reduction.

On the other hand, bio-based plastic refers to plastics containing 20 to 25% or more of biomass derived from plants such as corn. By using plant resources in which carbon dioxide in the atmosphere is fixed by photosynthesis as raw materials, the increase in the concentration of carbon dioxide in the atmosphere is suppressed. It has the effect of reducing the consumption of petroleum, which is a limited resource, and has recently attracted attention because it is decomposed by microorganisms after disposal.

Therefore, it is necessary to develop a technology for bioplastic with excellent biodegradability while exhibiting properties similar to existing petroleum-based plastic products by utilizing non-edible organic wastes such as agricultural waste, industrial waste, and food factory by-products, which are difficult to use for food.

Korean Patent Publication No. 10-2016-0091777

The present invention has been devised to solve the above problems, and by using wood flour as a waste resource, it exhibits properties similar to those of existing petroleum-based plastic products, has excellent biodegradability, and is a biodegradable polymer composite that can reduce carbon dioxide. An object of the present invention is to provide a method for manufacturing

Another object of the present invention is to provide a biodegradable polymer composite that can be widely used as a film, sheet, panel, packaging material, molded article, industrial material, etc. due to its excellent tensile strength, elongation rate and biodegradability.

In order to achieve the above object, the present invention comprises the steps of: (a) primary drying of wood flour;

(b) coating the surface of the wood powder by mixing the first dried wood flour and stearate;

(c) preparing a composition by mixing the coated wood flour, biodegradable polymer, inorganic filler, starch, lubricant, unsaturated fatty acid, organic acid and peroxide, followed by secondary drying; and

(d) provides a method for producing a biodegradable polymer composite comprising the step of extruding the composition to prepare a biodegradable polymer composite.

In one embodiment of the present invention, before step (c), mixing the coated wood powder and a surface treatment agent to modify the surface of the wood powder is characterized.

In one embodiment of the present invention, the biodegradable polymer is characterized in that at least one selected from polylactic acid and poly(butylene adipate-co-terephthalate) is used.

In one embodiment of the present invention, the unsaturated fatty acid is characterized in that at least one selected from oleic acid, linoleic acid, linolenic acid, arachidonic acid and palmitoleic acid is used.

The present invention also provides a biodegradable polymer composite prepared by the above manufacturing method.

In addition, the present invention provides a product prepared from the biodegradable polymer composite.

In one embodiment of the present invention, the product is characterized in that the film, sheet or panel.

The present invention can provide a method for producing a biodegradable polymer composite that can exhibit properties similar to existing petroleum-based plastic products, excellent biodegradability, and exhibit a carbon dioxide reduction effect by utilizing wood flour as a waste resource.

In addition, the present invention can provide a biodegradable polymer composite that can be widely used as a film, sheet, panel, packaging material, molded article, industrial material, etc., excellent in tensile strength, elongation rate and biodegradability.

Hereinafter, the present invention will be described in detail based on Examples. The terms, examples, etc. used in the present invention are merely exemplified to explain the present invention in more detail and help those of ordinary skill in the art to understand, and the scope of the present invention should not be construed as being limited thereto.

Technical terms and scientific terms used in the present invention represent meanings commonly understood by those of ordinary skill in the art to which this invention belongs, unless otherwise defined.

The present invention comprises the steps of: (a) primary drying of wood flour;

(b) coating the surface of the wood powder by mixing the first dried wood flour and stearate;

(c) preparing a composition by mixing the coated wood flour, biodegradable polymer, inorganic filler, starch, lubricant, unsaturated fatty acid, organic acid and peroxide, followed by secondary drying; and

(d) relates to a method for producing a biodegradable polymer composite comprising the step of extruding the composition to prepare a biodegradable polymer composite.

Step (a) is a step of primary drying the wood flour, and the wood flour may be dried at 60-120° C. for 3 to 12 hours while stirring at 100 to 2,000 rpm under normal pressure or reduced pressure (0.01 to 0.1 MPa).

The wood powder is finely pulverized wood, and sawdust, pine powder, acacia wood powder, rubber wood powder, etc. may be used.

In this case, the wood powder may be pulverized into fine particles, and the size of the pulverized particles is preferably 60 to 200 mesh. When the particle size satisfies the above numerical range, tensile strength, biodegradability and processability can be maximized.

In addition, the moisture content of the primary dried wood flour is preferably 5 to 15%, and when the moisture content satisfies the numerical range, tensile strength, biodegradability and processability can be maximized.

Step (b) is a step of coating the surface of the wood powder by mixing the primary dried wood powder and stearate.

The stearate is coated on the surface of the wood flour to serve as a lubricant, a surfactant, and a mold release agent, and it is possible to prevent the wood flour powder from coagulating and increase the particle size, and to improve dispersibility and processability.

One or more of zinc stearate, calcium stearate, magnesium stearate, sodium stearate, potassium stearate, and the like may be used as the stearate.

The stearate is preferably used in an amount of 1 to 10 parts by weight based on 100 parts by weight of the primary dried wood flour, and when the content satisfies the above numerical range, tensile strength, biodegradability and processability can be maximized.

In addition, in the present invention, zinc stearate and sodium stearate can be used simultaneously as stearate, and in this case, the weight ratio of zinc stearate and sodium stearate is preferably 60 to 90:10 to 40, and tensile strength when the weight ratio satisfies the above numerical range , biodegradability and processability can be maximized.

In the present invention, zinc stearate, sodium stearate and potassium stearate may be used simultaneously as stearate salts, and in this case, the weight ratio of zinc stearate, sodium stearate and potassium stearate is preferably 100:20-40:5-15, and the weight ratio is When the numerical range is satisfied, tensile strength, biodegradability and processability can be maximized.

Step (c) is a step of preparing a composition by mixing the coated wood flour, biodegradable polymer, inorganic filler, starch, lubricant, unsaturated fatty acid, organic acid and peroxide, and then drying the mixture.

The composition comprises 10 to 50% by weight of coated wood flour, 30 to 70% by weight of biodegradable polymer, 10 to 30% by weight of inorganic fillers, 1 to 10% by weight of starch, 1 to 5% by weight of lubricant, 1 to 10% by weight of unsaturated fatty acids , it may contain 0.1 to 10% by weight of organic acid and 0.1 to 10% by weight of peroxide.

The secondary drying may be performed at 60 to 120° C. for 30 minutes to 5 hours while stirring at 100 to 2,000 rpm under normal pressure or reduced pressure (0.01 to 0.1 MPa).

The coated wood powder performs chemical bonding with the biodegradable polymer, and through this, the tensile strength and biodegradability of the composition can be improved.

The content of the coated wood flour is preferably 10 to 50% by weight, and when the content satisfies the above numerical range, tensile strength, biodegradability and processability can be maximized.

The biodegradable polymer may be one or more selected from polylactic acid (PLA) and poly(butylene adipate-co-terephthalate) (PBAT).

The biodegradable polymer serves as a binder for binding the composition, and the content of the biodegradable polymer is preferably 30 to 70% by weight. When the content satisfies the above numerical range, tensile strength, biodegradability and processability can be maximized.

The inorganic filler may be one or more selected from calcium carbonate, silica, alumina, titanium dioxide, zeolite, clay, loess, talc and kaolin.

The content of the inorganic filler is preferably 10 to 30% by weight, and when the content satisfies the above numerical range, tensile strength, biodegradability and processability can be maximized.

One or more starches may be used in sweet potato, potato, tapioca, corn, wheat, rice starch, and the like, and the starch content is preferably 1 to 10% by weight. When the content satisfies the above numerical range, tensile strength, biodegradability and processability can be maximized.

At least one lubricant may be used from the group consisting of paraffin wax, liquid paraffin wax, beeswax, molda wax, emulsifying wax, candelilla wax, PE wax, and PP wax.

The content of the lubricant is preferably 1 to 5% by weight, and when the content satisfies the above numerical range, tensile strength, biodegradability and processability can be maximized.

The unsaturated fatty acid may be used at least one selected from oleic acid, linoleic acid, linolenic acid, arachidonic acid and palmitoleic acid.

The content of unsaturated fatty acids is preferably 1 to 10% by weight, and when the content satisfies the above numerical range, tensile strength, biodegradability and processability can be maximized.

The organic acid may be one or more selected from citric acid, malic acid, maleic acid and acetic acid, and the content of the organic acid is preferably 0.1 to 10% by weight. When the content satisfies the above numerical range, tensile strength, biodegradability and processability can be maximized.

The peroxide is benzoyl peroxide, benzopinone, azo-bis-isobutyronitrile, t-butyl hydroperoxide, dicumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di ( t-Butylperoxy)hexane (2,5-Dimethyl-2,5-di(t-butylperoxy)hexane) and 1,3-bis(t-butylperoxy-isopropyl)benzene (1,3-Bis( At least one selected from t-butylperoxy-isoproply)benzene) may be used.

The content of the peroxide is preferably 0.1 to 10% by weight, and when the content satisfies the above numerical range, tensile strength, biodegradability and processability can be maximized.

The step (d) is a step of preparing a biodegradable polymer composite by extruding the composition, and a polymer composite such as pellets can be prepared through an extrusion molding machine.

The polymer composite may be manufactured into a film, a sheet, a panel, etc. through a later process.

Also, the present invention may include, before step (c), mixing the coated wood powder and a surface treatment agent to modify the surface of the wood powder.

The surface treatment agent may be used at least one of maleic anhydride, DL-lactide, butyl acrylate, and poly(butyl acrylate).

The surface treatment agent is preferably used in an amount of 3 to 15 parts by weight based on 100 parts by weight of the coated wood flour, and when the content satisfies the numerical range, tensile strength, biodegradability and processability can be maximized.

In addition, in the present invention, maleic anhydride and butyl acrylate can be used simultaneously as a surface treatment agent. In this case, the weight ratio of maleic anhydride and butyl acrylate is preferably 60 to 90:10 to 40, and the weight ratio satisfies the above numerical range. In this case, tensile strength, biodegradability and processability can be maximized.

In addition, in the present invention, maleic anhydride, butyl acrylate and polybutyl acrylate may be used simultaneously as a surface treatment agent, wherein the weight ratio of maleic anhydride, butyl acrylate and polybutyl acrylate is 100:20-40:5-15 Preferably, when the weight ratio satisfies the above numerical range, tensile strength, biodegradability and processability can be maximized.

In the present invention, a copolymer of an acrylate group-containing silane coupling agent, an acrylic acid-based monomer, and 2-hydroxyethyl acrylate (HEA) may be additionally used as a surface treatment agent.

The copolymer may combine with a functional group introduced to the surface of the wood powder, thereby improving tensile strength, biodegradability and processability.

The acrylate group-containing silane coupling agent includes 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltri ethoxysilane, 3-acryloxypropyltrimethoxysilane, methacryloxymethyltriethoxysilane, and methacryloxymethyltrimethoxysilane.

The acrylic acid-based monomer is acrylic acid, methacrylic acid, methyl acrylic acid, ethyl acrylic acid, butyl acrylic acid, 2-ethyl hexyl acrylic acid, decyl acrylic acid, methyl methacrylic acid, ethyl methacrylic acid, butyl methacrylic acid, 2-ethyl hexyl methacrylic acid acid, and decyl methacrylic acid.

The weight ratio of the acrylate group-containing silane coupling agent, the acrylic acid-based monomer and 2-hydroxyethyl acrylate is preferably 10 to 30:100:40 to 70.

The copolymer is preferably used in an amount of 1 to 10 parts by weight based on 100 parts by weight of the coated wood flour, and when the content satisfies the numerical range, tensile strength, biodegradability and processability can be maximized.

The present invention also relates to a biodegradable polymer composite prepared by the above method.

In addition, the present invention relates to a product prepared from the biodegradable polymer composite.

The present invention will be described in detail with reference to the following examples. The following examples are only exemplified for the practice of the present invention, and the content of the present invention is not limited by the following examples.

(Example 1)

The wood flour was pulverized using an ACM (Air Classifying Mill, Korea pulverizing machinery, Incheon, Korea) pulverizer. The pulverized wood flour powder (100mesh) was dried with hot air at 500 rpm and 80° C. for 5 hours using a cylindrical rotary dryer (D560, Hwain machinery, Wonju, Korea).

The dried wood powder and zinc stearate were mixed to coat the surface of the wood powder. At this time, 5 parts by weight of zinc stearate was used based on 100 parts by weight of the dried wood powder.

30% by weight of the coated wood flour, 40% by weight of polylactic acid, 18% by weight of calcium carbonate, 3% by weight of sweet potato starch, 2% by weight of paraffin wax, 3% by weight of oleic acid, 3% by weight of citric acid and 1% by weight of benzoyl peroxide are mixed After that, the composition was prepared by hot air drying at 500 rpm and 80° C. for 50 minutes.

The composition was extruded by an extruder to prepare a biodegradable polymer composite (pellet).

(Example 2)

A biodegradable polymer composite was prepared in the same manner as in Example 1, except that 3.5 parts by weight of zinc stearate and 1.5 parts by weight of sodium stearate were used instead of 5 parts by weight of zinc stearate.

(Example 3)

The wood flour was pulverized using an ACM (Air Classifying Mill, Korea pulverizing machinery, Incheon, Korea) pulverizer. The pulverized wood flour powder (100mesh) was dried with hot air at 500 rpm and 80° C. for 5 hours using a cylindrical rotary dryer (D560, Hwain machinery, Wonju, Korea).

The dried wood powder and zinc stearate were mixed to coat the surface of the wood powder. At this time, 5 parts by weight of zinc stearate was used based on 100 parts by weight of the dried wood powder.

100 parts by weight of the coated wood powder and 5 parts by weight of maleic anhydride were mixed to modify the surface of the wood powder.

30% by weight of the modified wood flour, 40% by weight of polylactic acid, 18% by weight of calcium carbonate, 3% by weight of sweet potato starch, 2% by weight of paraffin wax, 3% by weight of oleic acid, 3% by weight of citric acid and 1% by weight of benzoyl peroxide are mixed After that, the composition was prepared by hot air drying at 500 rpm and 80° C. for 50 minutes.

The composition was extruded with an extruder to prepare a biodegradable polymer composite.

(Example 4)

A biodegradable polymer composite was prepared in the same manner as in Example 3, except that 3.5 parts by weight of maleic anhydride and 1.5 parts by weight of butyl acrylate were used instead of 5 parts by weight of maleic anhydride.

(Example 5)

20 parts by weight of 3-methacryloxypropyltrimethoxysilane, 100 parts by weight of acrylic acid, and 60 parts by weight of 2-hydroxyethyl acrylate are reacted to form a silane coupling agent containing an acrylate group, an acrylic acid-based monomer and 2-hydroxyethyl acrylate (HEA) was prepared.

The wood flour was pulverized using an ACM (Air Classifying Mill, Korea pulverizing machinery, Incheon, Korea) pulverizer. The pulverized wood flour powder (100mesh) was dried with hot air at 500 rpm and 80° C. for 5 hours using a cylindrical rotary dryer (D560, Hwain machinery, Wonju, Korea).

The dried wood powder and zinc stearate were mixed to coat the surface of the wood powder. At this time, 5 parts by weight of zinc stearate was used based on 100 parts by weight of the dried wood powder.

100 parts by weight of the coated wood powder, 5 parts by weight of maleic anhydride, and 5 parts by weight of the copolymer were mixed to modify the surface of the wood powder.

30% by weight of the modified wood flour, 40% by weight of polylactic acid, 18% by weight of calcium carbonate, 3% by weight of sweet potato starch, 2% by weight of paraffin wax, 3% by weight of oleic acid, 3% by weight of citric acid and 1% by weight of benzoyl peroxide are mixed After that, the composition was prepared by hot air drying at 500 rpm and 80° C. for 50 minutes.

The composition was extruded with an extruder to prepare a biodegradable polymer composite.

(Comparative Example 1)

A biodegradable polymer composite was prepared in the same manner as in Example 1, except that the step of coating the surface of the wood powder by mixing the dried wood flour and zinc stearate was not performed.

(evaluation)

(1) Tensile strength

After preparing a sheet having a thickness of 2 mm from the biodegradable polymer composite prepared in Examples and Comparative Examples, tensile strength was measured.

(2) biodegradability

After preparing a film from the biodegradable polymer composite prepared in Examples and Comparative Examples, the degree of biodegradation was measured.

The biodegradability evaluation was performed in accordance with ASTM D 6952-04, and the degradability evaluation is divided into 3 stages. The biodegradability of the prepared samples was measured under composting conditions by the method of KSM-3100-1.

division Example comparative example One 2 3 4 5 One tensile strength
(MPa) 40.5 44.9 47.2 50.3 52.5 36.2 biodegradability
(%) 88.2 90.3 91.5 91.8 92.4 78.7

As can be seen from Table 1, Examples 1 to 5 of the present invention are excellent in tensile strength and biodegradability.

On the other hand, in Comparative Example 1, it can be seen that the above characteristics are lowered than in Example.

Claims (5)

(a) first drying the wood flour;
(b) coating the surface of the wood flour by mixing the first dried wood flour and stearate;
(c) mixing the coated wood powder and a surface treatment agent to modify the surface of the wood powder;
(d) mixing the modified wood flour, biodegradable polymer, inorganic filler, starch, lubricant, unsaturated fatty acid, organic acid and peroxide, followed by secondary drying to prepare a composition; and
In the method for producing a biodegradable polymer composite comprising the step of (e) extruding the composition to prepare a biodegradable polymer composite,
The surface treatment agent uses maleic anhydride and butyl acrylate at the same time,
The weight ratio of maleic anhydride and butyl acrylate is 60-90:10-40,
The method for producing a biodegradable polymer composite, characterized in that the surface treatment agent is used in an amount of 3 to 15 parts by weight based on 100 parts by weight of the coated wood flour.
delete According to claim 1,
The biodegradable polymer is a method for producing a biodegradable polymer composite, characterized in that at least one selected from polylactic acid and poly (butylene adipate-co-terephthalate) is used.
According to claim 1,
The unsaturated fatty acid is oleic acid, linoleic acid, linolenic acid, arachidonic acid, and a method for producing a biodegradable polymer composite, characterized in that at least one selected from palmitoleic acid is used.
A biodegradable polymer composite prepared by the method of claim 1.