KR102415879B1 - Eco-friendly biodegradable plastic composite comprising wood flour and method for manufacturing the same - Google Patents

Abstract

The present invention relates to an eco-friendly biodegradable wood flour plastic and a manufacturing method thereof. The eco-friendly biodegradable wood flour plastic is prepared by a precursor composition comprising: 0.01 to 15 % by weight of polylactic acid, 50 to 90 % by weight of polybutylene adipate terephthalate, 1 to 30 % by weight of wood flour, 0.01 to 30 % by weight of calcium carbonate (CaCO_3), 0.01 to 1.0 % by weight of a phenolic oxidation agent, 0.01 to 0.5 % by weight of a slip agent; 0.01 to 3 % by weight of titanium dioxide, 0.01 to 3 % by weight of magnesium stearate (MgSt); and 0.01 to 2 % by weight of 2-ethylhexyl cocoate, wherein the precursor composition has an absorption rate of 5 to 8 % for light with a wavelength of 300 to 400 nm.

Description

Eco-friendly biodegradable wood flour plastic and manufacturing method thereof

The present invention relates to an eco-friendly biodegradable wood flour plastic and a manufacturing method thereof, and to an eco-friendly biodegradable wood flour plastic having excellent biodegradability and excellent physical properties while having excellent aesthetics and touch using wood flour and a method for manufacturing the same.

Plastic products are easy to process and inexpensive, so they are manufactured and used for various purposes in many fields.

However, most of the waste plastics after use depend on incineration or landfill, and in the case of incineration, harmful substances such as dioxins are generated, there is a problem of discharging environmental hormones, and even if buried in soil, the decomposition period is more than 500 years. Therefore, there is a problem of causing global environmental pollution.

In order to solve this problem, research on biodegradable materials that can replace conventional plastics is being actively conducted.

Biodegradable plastics have been developed to be biochemically decomposable by microorganisms into carbon dioxide and water, and improve biodegradability by reducing the time to decompose after being discarded, but have properties that are difficult to apply to various existing plastic materials, or , there was a problem of giving a hard, cold feeling and touch.

On the other hand, polymer materials developed as biodegradable plastics include starch, cellulose, hemi-cellulose, chitin and protein as natural polymers, and chemically synthesized polymers include PCL (Polycaprolactone), PLA (Polylacticacid)], PG (Polyglycolicacid), and the like, and PHB (Polyhydroxybutyricacid) is a microorganism-producing polymer.

In order to solve problems such as mechanical properties, weather resistance, and discoloration in addition to biodegradability, biodegradable plastics are used in a form that supplements weak physical properties by using two or more resins together rather than using a single resin.

Republic of Korea Patent No. 1755892 relates to a method for manufacturing a bioplastic composite using wood flour and a bioplastic composite produced thereby, a dry grinding step of drying and pulverizing wood to obtain wood flour, and agitating the wood flour with a chemical solvent and then filtration and drying the filtered wood powder to recover the solid components of the wood powder, an impregnating step of impregnating the recovered wood powder with polypropylene grafted with liquid maleic anhydride, a drying step of drying the impregnated wood powder, and A bioplastic having uniform appearance of a final product by mixing polypropylene resin and additives with wood flour after the drying step and extrusion molding, and a manufacturing method thereof are presented.

Republic of Korea Patent Publication No. 2014-0032130 relates to an eco-friendly bio-wood plastic composite and a method for manufacturing the same, and includes bio-resin derived from natural resources in addition to wood flour to improve physical properties such as compression and impact strength, while recyclable An eco-friendly bio-wood plastic composite is presented.

As such, while having biodegradability, the development of a plastic material that has properties suitable for use as a plastic product and provides a soft aesthetic and tactile feel is continuously required.

(0001) Republic of Korea Patent No. 1755892 (2017.07.07) (0002) Republic of Korea Patent Registration No. 2014-003230 (2014.03.14)

An object of the present invention is to provide a biodegradable plastic using wood flour.

An object of the present invention is to improve the cold feeling and tactile feel of existing biodegradable plastics using wood flour, which is a nature-friendly material.

An object of the present invention is to prevent environmental pollution due to the generation of waste plastics because it is biodegradable in nature.

An object of the present invention is to provide a biodegradable plastic satisfying aesthetic, tactile and physical properties applicable to plastic articles used in daily life, and a method for manufacturing the same.

The biodegradable wood powder plastic according to the present invention for solving the above problems,

PLA (Polylactic acid) 0.01 to 15 wt%, PBAT (Polybutylene adipate terephthalate) 50 to 90 wt%, Wood flour 1 to 30 wt%, Calcium carbonate (CaCO ₃ ) 0.01 to 30 wt%, Phenolic antioxidant 0.01 to 1.0 wt%, slip agent 0.01 to 0.5 wt%, titanium dioxide 0.01 to 3 wt%, magnesium stearate (MgSt, Magnesium Stearate) 0.01 to 3 wt%, and 2-Ethylhexyl cocoate 0.01 to prepared as a pre-structure comprising 2% by weight, or,

PLA (Polylactic acid) 5 to 10 wt%, PBAT (Polybutylene adipate terephthalate) 60 to 70 wt%, wood flour 3 to 10 wt%, Calcium carbonate (CaCO ₃ ) 15 to 20 wt%, phenolic antioxidant 0.01 to 0.5 wt%, slip agent 0.1 to 0.5 wt%, titanium dioxide 0.1 to 1 wt%, magnesium stearate (MgSt, Magnesium Stearate) 0.5 to 2 wt%, and 2-Ethylhexyl cocoate 0.01 to can be prepared as a precursor composition comprising 2% by weight,

The precursor composition has a composition having an absorption rate of 5 to 8% for light having a wavelength of 300 to 400 nm (nanometers).

More specifically, the precursor composition may contain 0.1 to 1% by weight of 2-Ethylhexyl cocoate.

The method for producing biodegradable wood flour plastic according to the present invention,

(a) PLA (Polylactic acid), PBAT (Polybutylene adipate terephthalate), wood flour, calcium carbonate, phenolic antioxidant, slip agent, titanium dioxide, magnesium stearate and 2-ethylhexyl cocoate are placed in a blender and preparing a precursor composition by mixing under temperature conditions for 10 to 20 minutes;

(b) putting the precursor composition into an extruder and extruding at a set temperature of 200 to 250°C; and

(c) drying the extrudate prepared in step (b) at a temperature of 78 to 82° C. for 3 hours or more;

including,

Step (b) is performed in a vacuum chamber,

Step (b) further includes cooling the extruded extrudate with cooling water.

In the manufacturing method according to the present invention, the biodegradable wood flour plastic may have a moisture content of less than 0.1%.

In the manufacturing method according to the present invention, the step (a) further includes (a-1) irradiating light with a wavelength of 300 to 400 nm to the precursor composition that has undergone step (a) for 10 to 15 minutes can do.

According to the present invention, there is an effect of having a soft, natural and eco-friendly aesthetic and tactile feel, unlike the cold feeling and tactile feel of conventional biodegradable plastics.

The present invention can prevent environmental pollution due to the generation of waste plastic because it is biodegradable in nature.

The present invention provides a soft aesthetic and tactile feel, and excellent moldability, strength, and durability during manufacturing, so that it can be manufactured into a plastic article used in daily life.

The present invention also has the effect of spreading awareness of environmental pollution widely by providing an environmentally friendly feeling and a warm aesthetic and tactile characteristic of wood when applied to various living articles made of plastic material.

1 is a graph showing the light absorptance (%) of Examples and Comparative Examples.
2 is a graph showing the tensile strength measurement results of Examples and Comparative Examples.
3 is a graph showing the impact strength measurement results of Examples and Comparative Examples.

Hereinafter, each configuration of the present invention will be described in more detail so that those of ordinary skill in the art to which the present invention pertains can easily carry out, but this is only an example, and the scope of the present invention is defined by the following contents Not limited.

As used herein, "preferred" or "preferably" refers to an embodiment of the invention that has certain advantages under certain conditions. However, other embodiments may also be preferred under the same or different conditions. Furthermore, one or more preferred embodiments do not mean that other embodiments are not useful, nor do they exclude other embodiments that are within the scope of the present invention.

As used herein, the term "comprises" is used to enumerate materials, compositions, devices, and methods useful in the present invention and is not limited to the enumerated examples.

The present invention relates to a biodegradable wood flour plastic having excellent biodegradability and mechanical properties of the plastic, and a method for manufacturing the same, while utilizing wood flour to have a soft, natural and eco-friendly aesthetic and tactile feel, unlike the cold feeling and tactile feel of conventional biodegradable plastics.

The biodegradable wood flour plastic according to the present invention is biodegradable in nature, so it is possible to prevent environmental pollution due to the generation of waste plastic, and it is suitable for application to various plastic articles such as cell phone cases, computer equipment, and electronic device housings before disposal. It is characterized by having physical properties.

In particular, by using the biodegradable wood flour plastic according to the present invention to construct an article made of a plastic material that is easily encountered in daily life, it provides a friendly feeling and a warm aesthetic and tactile characteristic unique to wood, while spreading awareness of environmental pollution widely have the advantage of being able to

Specifically, the biodegradable wood powder plastic according to the present invention,

PLA (Polylactic acid) 0.01 to 15% by weight, PBAT (Polybutylene adipate terephthalate) 50 to 90% by weight, wood flour 1 to 30% by weight, calcium carbonate (CaCO3) 0.01 to 30% by weight, phenolic antioxidant 0.01 to 1.0 wt%, slip agent 0.01 to 0.5 wt%, titanium dioxide 0.01 to 3 wt%, magnesium stearate (MgSt, Magnesium Stearate) 0.01 to 3 wt%, and 2-Ethylhexyl cocoate 0.01 to 2 It is prepared as a pre-structural composition comprising % by weight,

More preferably, PLA (Polylactic acid) 5 to 10% by weight, PBAT (Polybutylene adipate terephthalate) 60 to 70% by weight, wood flour 3 to 10% by weight, calcium carbonate (Calcium carbonate, CaCO ₃ ) 15 to 20% by weight, 0.01 to 0.5 wt% of a phenolic antioxidant, 0.1 to 0.5 wt% of a slip agent, 0.1 to 1 wt% of titanium dioxide, 0.5 to 2 wt% of magnesium stearate (MgSt, Magnesium Stearate), and 0.01 to 2 wt% of 2-ethylhexyl cocoate It may be prepared as a precursor composition comprising % by weight.

In addition, the precursor composition has a configuration in which the absorption rate for light having a wavelength of 300 to 400 nm (nanometers) is 5 to 8%.

Hereinafter, the configuration of the present invention will be described in detail.

1) Biodegradable plastic

According to the American Society for Testing and Materials (ASTM), "biodegradable plastic refers to a plastic whose chemical structure changes significantly under certain environmental conditions for a certain period of time and whose properties can be measured by standard test methods. Biodegradable plastics”.

However, it is generally used to mean “a so-called rotting plastic whose physical and chemical structure is made cotton by organic substances such as bacteria in nature”, and natural polymers include starch, cellulose, hemi-cellulose, chitin and protein. , chemically synthesized polymers include PCL (Polycaprolactone), PLA (Polylacticacid)], PG (Polyglycolicacid), and the like, and PHB (Polyhydroxybutyricacid), etc., is a representative polymer produced by microorganisms.

In the present invention, a biodegradable wood powder plastic having excellent biodegradability and improved physical properties is provided by utilizing a mixed biodegradable plastic containing PLA and PBAT in a predetermined content, which is widely known as a biodegradable plastic.

PLA, called polylactic acid and polylactide, is a biodegradable resin mainly made from plants such as corn and sugar cane. It is a polymer with lactic acid as a unit and is polymerized using lactic anhydride. It is produced the most among biodegradable high molecular compounds worldwide, and the hydrolysis product is lactic acid, so it is not toxic to the living body, but has a disadvantage in that the surrounding pH is lowered during decomposition. By itself, the mechanical strength is not good, but it is harmless to the human body, can be produced from biomass, and has the advantage of excellent processability.

On the other hand, PBAT and polybutylene adipate terephthalate are petroleum-based biodegradable plastics, and have the advantages of high decomposition rate and excellent flexibility and processability.

In the present invention, based on the total weight of the precursor composition for the production of plastic, 0.01 to 15% by weight of PLA (Polylactic acid), more preferably, 5 to 10% by weight and 50 to 90% by weight of PBAT (Polybutylene adipate terephthalate) %, more preferably, a wood powder plastic is prepared from a precursor composition comprising 60 to 70% by weight.

When PLA is included in a small amount than the above content, there is a problem that the impact strength is lowered and the biodegradability is lowered, and when PLA is included in excess than the above content, the tensile strength is lowered, and it is difficult to apply to various plastic articles. have.

In particular, when the content ratio of PLA and PBAT is out of the above numerical range, there is a problem that the biodegradability is rather reduced, which is optimal not only with the content ratio of the two resins, but also with the content ratio of other additives added together. This is because optimal biodegradability is shown when formulated in a ratio.

2) Wood flour

Wood flour may be prepared by pulverizing untreated wood, or may be used as derived from waste wood. However, it is preferable to use wood powder having a non-uniform size and having a maximum diameter of 2 to 5 mm.

When the particle size is larger than the particle size, it is difficult to extrude, and when processing into a plastic article, restrictions such as thickness or size occur, so it is preferable to use wood flour within the above range.

On the other hand, when the particle size is smaller than the particle size, there is a problem in that the light absorption rate is greatly lowered and the viscosity of the precursor composition is greatly increased, which in turn makes it difficult to perform the extrusion process and causes deterioration of the physical properties of the plastic.

The wood powder may be included in an amount of 1 to 30 wt%, more preferably, 3 to 10 wt%, based on the total weight of the precursor composition.

If it exceeds the above content, there may be a problem in that the hardness of the final finished product is lowered.

3) Others

In addition, calcium carbonate (CaCO ₃ ), phenolic antioxidant, slip agent, titanium dioxide, magnesium stearate and 2-ethylhexyl cocoate were added to the precursor composition for producing the biodegradable wood powder plastic of the present invention. do.

If necessary, additional additives may be added in addition to the above components, but it is preferable to include the above components so as to simultaneously satisfy optimal mechanical properties and biodegradability.

More specifically, calcium carbonate (CaCO ₃ ) 0.01 to 30% by weight, phenolic antioxidant 0.01 to 1.0% by weight, slip agent 0.01 to 0.5% by weight, titanium dioxide 0.01 to 3% by weight, magnesium stearate ( MgSt, Magnesium Stearate) 0.01 to 3% by weight and 2-Ethylhexyl cocoate (2-Ethylhexyl cocoate) 0.01 to 2% by weight,

Most preferably, 15 to 20% by weight of calcium carbonate (CaCO ₃ ), 0.01 to 0.5% by weight of a phenolic antioxidant, 0.1 to 0.5% by weight of a slip agent, 0.1 to 1% by weight of titanium dioxide, magnesium stearate ( MgSt, Magnesium Stearate) 0.5 to 2% by weight and 2-ethylhexyl cocoate (2-Ethylhexyl cocoate) 0.01 to 2% by weight may be included.

In particular, the 2-ethylhexyl cocoate is a component that provides excellent biodegradability and mechanical properties at the same time in the present invention, and by including it, has excellent properties in both biodegradability and physical properties.

More preferably, 2-ethylhexyl cocoate may contain 0.1 to 1% by weight.

When it is included in excess, the content of other additives is reduced, and extrudability or miscibility cannot be sufficiently secured.

4) Manufacturing method

On the other hand, the manufacturing method of the biodegradable wood flour plastic according to the present invention,

(a) PLA (Polylactic acid), PBAT (Polybutylene adipate terephthalate), wood flour, calcium carbonate, phenolic antioxidant, slip agent, titanium dioxide, magnesium stearate and 2-ethylhexyl cocoate are placed in a blender and preparing a precursor composition by mixing under temperature conditions for 10 to 20 minutes;

(b) putting the precursor composition into an extruder and extruding at a set temperature of 200 to 250°C; and

(c) drying the extrudate prepared in step (b) at a temperature of 78 to 82° C. for 3 hours or more;

including,

Step (b) is performed in a vacuum chamber,

Step (b) may further include cooling the extruded extrudate with cooling water.

In step (a), more preferably, 2-ethylhexyl cocoate may be further included, and most preferably, it may be added when 40 to 60% of the total mixing time is reached.

By adding in this way, it is possible to prevent problems in that calcium carbonate or titanium dioxide and 2-ethylhexyl cocoate are first bound, so that they are not sufficiently mixed in the precursor composition, and the mechanical properties of the plastic are not sufficiently improved compared to the amount added.

The temperature condition of step (a) is maintained at less than 30°C, preferably at least 15°C or more and less than 30°C.

The method may further include (a-1) irradiating light with a wavelength of 300 to 400 nm to the precursor composition that has undergone step (a) for 10 to 15 minutes.

By performing such a process, the mechanical properties of the plastic can be further improved.

The precursor composition that has passed through the above steps may have an absorption rate of 5 to 8% for light having a wavelength of 300 to 400 nm (nanometers).

The absorptivity refers to a ratio of light excluding reflected or transmitted light compared to light before passing through the sample as an absorptivity. There is no particular limitation on the method, such as indirectly obtaining the absorption rate using equipment capable of measuring light reflection and transmittance.

More preferably, the absorption rate for light having a wavelength of 300 to 400 nm (nanometers) after irradiating light through the above steps may be 6 to 7%.

When the light absorption rate in the above range is satisfied, the precursor composition may be uniformly mixed throughout the composition to exhibit uniformly excellent mechanical properties throughout the plastic product manufactured using the same.

Step (b) extrudes the set temperature at the time of extrusion to 200 to 250 ℃.

If it is set to a temperature higher than the above temperature, a portion of the precursor composition is carbonized and deformed darkly, or there is a problem of poor extrudability due to insufficient flowability.

If it is set to a temperature lower than the above temperature, there is a problem in that the bonding force of the extrudate is lowered, and mechanical properties are lowered.

The step (b) is performed in a vacuum chamber, and the step (b) may further include cooling the extruded product with cooling water.

By performing the step of cooling prior to drying, it is possible to prevent the formation of cracks on the surface of the extrudate due to rapid evaporation of moisture, thereby preventing deterioration of mechanical properties.

Step (c) is a process of drying the manufactured extrudate at a temperature of 78 to 82° C. for 3 hours or more, and although there is no time limit, the biodegradable wood powder plastic is dried until the moisture content is less than 0.1%. do. In addition, although there is no lower limit of the moisture content, it may be 0% or more.

When drying at a temperature higher than the above temperature, the inside of the extrudate is not sufficiently dried and there is a problem that mechanical properties are rather deteriorated. there is a problem.

Hereinafter, it will be described in more detail based on the embodiments of the present invention, but these are merely exemplary descriptions for the understanding of the present invention, and the scope of the present invention is not limited or limited to the following examples.

<Example 1>

Based on the total weight of 75 kg in the batch, 9 wt % PLA LX-130 (injected), 62 wt % PBAT, 5 wt % wood flour (within 2 to 5 mm diameter max.), 17.5 wt % carbonate HB-2T, A/O 60 (phenolic antioxidant) 0.2% by weight, A/O 2112 (phenolic antioxidant) 0.18% by weight, INNOSLIP E (slip agent) 0.12% by weight, titanium dioxide 0.9% by weight, MgSt 1% by weight, 2-ethylhexyl Cocoate 0.5% by weight and PRO P-3 3.6% by weight were added and blended for 15 minutes at a temperature of less than 30° C. to prepare a precursor composition.

Among them, 0.5 wt % of 2-ethylhexyl cocoate was mixed with the other components by mixing after about 7 to 8 minutes had elapsed.

After irradiating light with a wavelength of 300 to 400 nm for 12 minutes, the precursor composition was extruded in the form of pellets having a diameter of 10 mm at a set temperature of 200 to 250° C. under vacuum conditions.

The extrudate is immediately cooled using cooling water, then maintained at a temperature of 80° C. and dried for 3 hours or more to stop drying when the moisture content is confirmed to be less than 0.1% based on the total weight to produce a biodegradable wood flour plastic extrudate did

<Comparative Example 1>

To prepare the precursor composition, PLA LX-130 (injection) 4% by weight, PBAT 67% by weight, wood flour (within 2 to 5 mm in diameter) 5% by weight, carbonic acid HB-2T 17.5% by weight, A/O 60 ( Phenolic antioxidant) 0.2 wt%, A/O 2112 (phenolic antioxidant) 0.18 wt%, INNOSLIP E (slip agent) 0.12 wt%, titanium dioxide 0.9 wt%, MgSt 1 wt%, 2-ethylhexyl cocoate A biodegradable wood flour plastic extrudate was prepared in the same manner as in Example 1, except that 0.5 wt% and 3.6 wt% of PRO P-3 were added.

<Comparative Example 2>

PLA LX-130 (injection) 20% by weight, PBAT 51% by weight, wood flour (within 2 to 5 mm in diameter) 5% by weight, HB-2T carbonate 18% by weight, A/O 60 (phenolic antioxidant) 0.2% by weight %, A/O 2112 (phenolic antioxidant) 0.18 wt%, INNOSLIP E (slip agent) 0.12 wt%, titanium dioxide 0.9 wt%, MgSt 1 wt%, PRO P-3 3.6 wt% A biodegradable wood flour plastic extrudate was prepared in the same manner as in Example 1.

<Comparative Example 3>

To prepare the precursor composition, PLA LX-130 (injection) 9% by weight, PBAT 62% by weight, wood flour (maximum diameter 1 mm or less) 5% by weight, HB-2T carbonate 17.5% by weight, A/O 60 (phenolic) Antioxidant) 0.2% by weight, A/O 2112 (phenolic antioxidant) 0.18% by weight, INNOSLIP E (slip agent) 0.12% by weight, titanium dioxide 0.9% by weight, MgSt 1% by weight, 2-ethylhexylcocoate 0.5% by weight %, a biodegradable wood flour plastic extrudate was prepared in the same manner as in Example 1, except that 3.6 wt% of PRO P-3 was added.

<Comparative Example 4>

Based on 75 kg total weight in batch, 9 wt% PLA LX-130 (injection), 62 wt% PBAT, 5 wt% wood flour (within 2-5 mm diameter max.), 18 wt% carbonate HB-2T, A/O 60 (phenolic antioxidant) 0.2% by weight, A/O 2112 (phenolic antioxidant) 0.18% by weight, INNOSLIP E (slip agent) 0.12% by weight, titanium dioxide 0.9% by weight, MgSt 1% by weight, PRO P-3 A biodegradable wood flour plastic extrudate was prepared in the same manner as in Example 1, except that 3.6 wt% was added.

[Physical evaluation]

1) Measurement of Light Absorption Rate of Bulb Composition

Before performing the step of irradiating light with a wavelength of 300 to 400 nm during the manufacturing process, the light absorption rate of the precursor composition was measured (A), and the light absorption rate was measured after irradiating the light (B).

2) Extrusion test

Using a screw extruder, S-RPM 140, F-RPM 30, and C-RPM 2000 were respectively set, and then PP (polypropylene) was added instead of PLA and PBAT of Example 1 to prepare an extrudate.

Compared to the extrusion rate per hour of PP, the extrusion rates of Examples and Comparative Examples were compared and expressed as a ratio.

3) Measurement of tensile strength

A tensile strength test was performed on each specimen according to ASTM D638 using a universal testing machine.

4) Impact strength measurement

Impact strength test was performed on each specimen according to ASTM D256.

5) Assessment of biodegradability (%)

According to ISO 14855-1 (aerobic biodegradation test), 200 g of each specimen is freeze-ground to produce granules with a maximum diameter of 5 mm or less, and the biodegradability (%) evaluation is performed for 90 days in the dark by mixing it with biodegradable compost. did

When a decomposition rate of 90% or more was confirmed, it was evaluated as suitable, and when it was less than 90%, it was evaluated as unsuitable.

Results according to the above experimental examples are shown in Table 1 and FIGS. 1 to 3 below.

Example 1 (A) Example 1 (B) Comparative Example 1 (A) Comparative Example 1 (B) Comparative Example 2 (A) Comparative Example 2 (B) Comparative Example 3 (A) Comparative Example 3 (B) Comparative Example 4 light absorption
(%) 8 6 18 15 13 12 3 3 6 Extrudability (Relative Speed Ratio, %) 91 92 89 91 90 92 50 46 90 The tensile strength
(MPa) 30 38 32 36 25 27 26 29 15 impact strength
(kgcm/cm) 8 9 4 6 8 8 9 7 4 biodegradability fitness fitness incongruity incongruity incongruity incongruity incongruity incongruity incongruity

1 is a graph showing the light absorption rate (%) of Examples and Comparative Examples, FIG. 2 is a graph showing tensile strength measurement results of Examples and Comparative Examples, and FIG. 3 is a graph showing the impact strength measurement results of Examples and Comparative Examples to be.

Referring to Table 1 and FIGS. 1 to 3, in the case of Comparative Example 1, the extrudability is good, but there is a problem of low biodegradability. there is a problem.

Referring to Table 1, in the case of Comparative Example 1, the extrudability is good, but there is a problem of low biodegradability, and in the case of Comparative Example 2, there is a problem that not only the biodegradability is low, but also the tensile strength and physical properties are greatly deteriorated.

In Comparative Example 3, the particle size of the wood powder was too small, and as the viscosity of the precursor composition increased, it was difficult to uniformly mix the composition. Accordingly, there was a problem in that the composition was not uniformly extruded during extrusion and was extruded at a non-uniform speed. Moreover, it can be seen that the high viscosity precursor composition lowers the extrusion rate, thereby significantly reducing the extrudability.

Comparative Example 4 was a wood powder plastic prepared with a precursor composition not containing 2-ethylhexyl cocoate, and it was confirmed that the plastic properties were greatly deteriorated and the biodegradability was also low.

The biodegradable wood powder plastic of Example 1 was confirmed to have excellent plastic properties and a suitable level of biodegradability as well.

Accordingly, it is possible to manufacture various plastic articles using the biodegradable wood flour plastic having excellent physical properties while having an eco-friendly effect of providing the warmth and tactile feel of wood by using the wood flour.

On the other hand, when the process of irradiating the precursor composition of Example 1 with light having a wavelength of 300 to 400 nm, it can be seen that the tensile strength is greatly improved.

Claims (5)

PLA (Polylactic acid) 9 wt%, PBAT (Polybutylene adipate terephthalate) 62 wt%, wood flour 5 wt%, Calcium carbonate (CaCO ₃ ) 15 to 20 wt%, phenolic antioxidant 0.01 to 1.0 wt%, slip 0.01 to 0.5% by weight of titanium dioxide, 0.01 to 3% by weight of titanium dioxide, 0.01 to 3% by weight of magnesium stearate (MgSt, Magnesium Stearate), and 0.1 to 1% by weight of 2-Ethylhexyl cocoate prepared from a precursor composition,
The precursor composition is a biodegradable wood powder plastic having an absorption rate of 6% for light having a wavelength of 300 to 400 nm (nanometers).
delete A method for producing the biodegradable wood flour plastic according to claim 1, comprising:
(a) PLA (Polylactic acid), PBAT (Polybutylene adipate terephthalate), wood flour, calcium carbonate, phenolic antioxidant, slip agent, titanium dioxide, magnesium stearate and 2-ethylhexyl cocoate are placed in a blender and preparing a precursor composition by mixing under temperature conditions for 10 to 20 minutes;
(b) putting the precursor composition into an extruder and extruding at a set temperature of 200 to 250°C; and
(c) drying the extrudate prepared in step (b) at a temperature of 78 to 82° C. for 3 hours or more;
including,
Step (b) is performed in a vacuum chamber,
The step (b) is a method for producing a biodegradable wood flour plastic further comprising the step of cooling the extruded product with cooling water.
4. The method of claim 3,
The method for producing a biodegradable wood flour plastic in which the biodegradable wood flour plastic has a moisture content of less than 0.1% based on the total weight of the biodegradable wood flour plastic.
4. The method of claim 3,
The step (a) is,
(a-1) The method for producing a biodegradable wood powder plastic further comprising the step of irradiating light of a wavelength of 300 to 400 nm for 10 to 15 minutes to the precursor composition that has undergone step (a).

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