KR102284945B1 - Manufacturing method of acryl transparent wood and acryl transparent wood manufactured therefrom - Google Patents

Abstract

A method for producing transparent acrylic wood according to the present invention comprises: a first step of treating wood with a treatment solution containing a base and a sulfite; a second step of treating the treated wood with the treatment solution with hydrogen peroxide; a third step of impregnating the treated wood with the hydrogen peroxide water in an acrylic filling composition; and a fourth step of curing the acrylic filling composition.

Description

Method for manufacturing transparent acrylic wood and acrylic transparent wood manufactured therefrom

The present invention relates to a method for manufacturing an acrylic transparent wood and to an acrylic transparent wood manufactured therefrom.

Wood is a natural material that has been used for a long time and is one of the widely used materials because it has a characteristic structure including cellulose, which is the basic skeleton. In particular, most woods contain vertically aligned tubular structures to transport water and nutrients from the wood, through which water, ions and other components are transported.

These woods mainly contain cellulose, hemicellulose and lignin. Cellulose and hemicellulose are arranged in a tube shape in the longitudinal direction of the wood, and the average diameter of these tubes may vary depending on the type of wood and the size of the wood. Lignin is distributed between the cellulose tubes aligned in this way, and wood is strengthened by lignin, and studies are being actively conducted to utilize the cellulose structure of such wood.

Republic of Korea Patent Publication No. 10-2014-0032131

An object of the present invention is to provide a transparent wood excellent in light transmittance.

Another object of the present invention is to provide a transparent wood excellent in flexibility.

A method for producing transparent acrylic wood according to the present invention comprises: a first step of treating wood with a treatment solution containing a base and a sulfite;

a second step of treating the treated wood with the treatment solution with hydrogen peroxide;

a third step of impregnating the treated wood with the hydrogen peroxide water in an acrylic filling composition; and

and a fourth step of curing the acrylic filling composition.

In the method for manufacturing transparent acrylic wood according to an embodiment of the present invention, a weight ratio of hydrogen peroxide and water contained in the aqueous hydrogen peroxide solution may be 1:1 to 5.

In the transparent acrylic wood manufacturing method according to an embodiment of the present invention, the weight ratio of wood:acrylic resin in the transparent acrylic wood may be in a range of 1:3 to 7.

In the method for manufacturing a transparent acrylic wood according to an embodiment of the present invention, the molar ratio of the sulfite to the base may be 1:3 to 10.

In the method for manufacturing a transparent acrylic wood according to an embodiment of the present invention, the first step may be performed for 1 to 60 hours.

In the method for manufacturing a transparent acrylic wood according to an embodiment of the present invention, a washing step of removing a base and salt from the wood after the first step and before the second step may be further included.

In the method for manufacturing a transparent acrylic wood according to an embodiment of the present invention, the second step may be performed for 10 to 120 minutes.

In the transparent acrylic wood manufacturing method according to an embodiment of the present invention, the transparent acrylic wood may have a light transmittance of 80% or more in a wavelength range of 300 to 800 nm.

In the method for manufacturing a transparent acrylic wood according to an embodiment of the present invention, the transparent acrylic wood may have a tensile strength of 17 MPa or more.

In the method for manufacturing a transparent acrylic wood according to an embodiment of the present invention, the acrylic filling composition may include a hydroxy acrylic monomer including a hydroxy group and a high refractive acrylic monomer.

In the method for manufacturing transparent acrylic wood according to an embodiment of the present invention, the hydroxy acrylic monomer is 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate and 2-hydroxy It may include one or two or more selected from propyl acrylate.

In the method for manufacturing a transparent acrylic wood according to an embodiment of the present invention, the molar ratio of the hydroxy acrylic monomer to the high refractive acrylic monomer may be 1:0.7 to 1.4.

The present invention also provides a transparent acrylic wood, and the transparent acrylic wood according to the present invention may be manufactured by the method for manufacturing an acrylic transparent wood according to an embodiment of the present invention.

The transparent acrylic wood manufacturing method according to the present invention can exhibit high transparency by treating with hydrogen peroxide after treatment with a base and sulfite to remove lignin from the wood, and by filling and curing the acrylic, it has flexibility and elasticity even with an acrylic resin. It has the advantage of being able to manufacture excellent transparent wood.

1 is a view illustrating and visually observing the shape change of wood according to the manufacturing process of transparent wood.
Figure 2 shows the results of observing the transparent acrylic wood manufactured by the SEM of the present invention.
3 is a view showing the results of visually observing the transparency of the transparent acrylic wood prepared by the Preparation Example of the present invention.

Advantages and features of embodiments of the present invention, and methods of achieving them, will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

In describing the embodiments of the present invention, if it is determined that a detailed description of a well-known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, the terms to be described later are terms defined in consideration of functions in an embodiment of the present invention, which may vary according to intentions or customs of users and operators. Therefore, the definition should be made based on the content throughout this specification.

A method for producing transparent acrylic wood according to the present invention comprises: a first step of treating wood with a treatment solution containing a base and a sulfite;

a second step of treating the treated wood with the treatment solution with hydrogen peroxide;

a third step of impregnating the treated wood with the hydrogen peroxide water in an acrylic filling composition; and

and a fourth step of curing the acrylic filling composition.

The transparent acrylic wood according to the present invention has the advantage of being able to manufacture a transparent wood having high flexibility, excellent tensile strength, and high transparency by including the above-described steps.

In the method for manufacturing transparent acrylic wood according to the present invention, lignin is removed from the wood through the treatment processes of the first and second steps, and only the cellulose structure remains while the lignin is removed from the wood. By filling and curing the acrylic filling composition, it is possible to manufacture transparent acrylic wood that exhibits flexibility and has excellent mechanical strength. Specifically, by filling the cellulose structure with an acrylic resin, not only the tensile strength is strengthened, but also the flexibility is remarkably improved by the mesh structure of the cellulosic structure, which has a wide application field compared to a transparent structure such as glass.

Specifically, the first step includes a first step of treating the wood with a treatment solution containing a base and a sulfite. In this case, if the base is a water-soluble base, it can be used without limitation, and specifically, sodium hydroxide, potassium hydroxide, etc. can be used, but the present invention is not limited thereto. In addition, if the sulfite is also water-soluble, it can be used without limitation, and sodium sulfite or potassium sulfite can be preferably used, but the present invention is not limited thereto.

The molar ratio of sulfite to base in the treatment solution may be 1:3 to 10, specifically, 1:4 to 8. In addition, the concentration of the sulfite may be 0.4 mol/L, and by satisfying the molar ratio of the sulfite:base and the concentration of the sulfite, it is possible to maximize the lignin removal efficiency to prevent a decrease in transparency.

In addition, the first step may be performed at 90 to 110 ° C. conditions to remarkably improve the lignin removal efficiency and to prevent the problem of causing damage to cellulose by using a treatment solution under excessively severe conditions, and for 12 to 60 hours It can be carried out as a method of impregnating the wood in the treatment solution during the.

The method for manufacturing a transparent acrylic wood according to an embodiment of the present invention may further include a washing step of removing the base and sulfite remaining in the wood after the first step. By going through this washing step, it is possible to prevent the effect on the hydrogen peroxide treatment in the second step and remove the residual lignin together. In this case, the washing may be performed 1 to 10 times using distilled water or alcohol having 1 to 3 carbon atoms, but the last washing before performing the second step may be washed using distilled water.

The method for manufacturing transparent acrylic wood according to the present invention includes a second step of treating the wood treated with the treatment solution with hydrogen peroxide. By including this second step, it is possible to remove residual lignin, and to significantly improve the transparency of the transparent wood finally produced through the bleaching action. In this case, the weight ratio of hydrogen peroxide to water contained in the hydrogen peroxide solution may be 1: 1 to 5, specifically 1:2.5 to 4. By satisfying this range, it is possible to achieve a light transmittance of 80% or more in the range of 300 to 800 nm of the acrylic transparent wood manufactured. When water is added in a larger amount than the appropriate range, transparency may decrease, and if water is added in a small amount, the tensile strength and flexibility of transparent wood may deteriorate due to damage to cellulose tissue, etc.

In the method for producing transparent acrylic wood according to an embodiment of the present invention, the second step may be performed at 85 to 110° C. for 10 to 120 minutes, and within this range, the lignin remaining with bleaching is removed without damaging the cellulose tissue. There are possible advantages.

The method for manufacturing a transparent acrylic wood according to an embodiment of the present invention may further include washing and drying the wood after the second step and before performing the third step. In this case, washing may be performed using distilled water, and the drying may be used without limitation if it is a method capable of removing distilled water after washing.

The method for manufacturing a transparent acrylic wood according to the present invention includes a third step of impregnating the treated wood with the hydrogen peroxide solution into an acrylic filling composition and a fourth step of curing the acrylic filling composition. By including the third and fourth steps, by filling the acrylic between the cellulose structures remaining in the wood, it is possible to manufacture an acrylic transparent wood excellent in visible light transmittance.

At this time, the weight ratio of wood: acrylic resin contained in the finally manufactured transparent wood may be 1:3 to 8, specifically 1:4 to 7, and when the acrylic content is too low, the cellulose structure cannot be sufficiently filled and the mechanical strength There may be a problem that the acrylic is weakened, and when the acrylic content is too high, it is difficult to achieve the effect of increasing the elasticity by the cellulose structure.

The acrylic filling composition used at this time can be used without limitation in the case of a conventionally curable acrylic filling composition, and it is natural that it may vary depending on the place of use of the manufactured transparent wood.

Preferably, in the acrylic transparent wood manufacturing method according to an embodiment of the present invention, the acrylic filling composition may include a hydroxy acrylic monomer including a hydroxy group in order to secure flexibility while increasing the bonding force with the cellulose structure. can

The hydroxy acrylic monomer may preferably be one or two or more selected from 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate. . There is an advantage in that adhesion with the cellulose structure can be increased by using the hydroxy acrylic monomer.

Furthermore, in the method for manufacturing a transparent acrylic wood according to an embodiment of the present invention, the acrylic filling composition may further include a high refractive monomer having a high refractive index when cured together with the hydroxy acrylic monomer. By including a high refractive monomer, there is an advantage in that the adhesion to the cellulose structure is increased, and flexibility and tensile strength can be secured.

In this case, the high refractive monomer is phenoxyethyl methacrylate, phenoxy-2-methylethyl methacrylate, phenoxyethoxyethyl methacrylate, 3-hydroxy-2-hydroxypropyl methacrylate, benzyl methacrylate , Phenylthioethyl acrylate, 2-naphthylthioethyl acrylate, 1-naphthylthioethyl acrylate, 2,4,6-tribromophenoxyethyl acrylate, 2,4-dibromophenoxyethyl acrylate , 2-bromophenoxyethyl acrylate, 1-naphthyloxyethyl acrylate, 2-naphthyloxyethyl acrylate, phenoxy 2-methylethyl acrylate, phenoxyethoxyethyl acrylate and 3-phenoxy It may be one or two or more selected from -2-hydroxypropyl acrylate.

When the acrylic filling composition includes a hydroxy acrylic monomer and a high refractive monomer together, the molar ratio of the acrylic monomer to the high refractive monomer may be 1:0.7 to 1.4, preferably 1:0.8 to 1.2. When this range is satisfied, the tensile strain of the produced acrylic transparent wood may be 2% or more, preferably 2.2% or more,

It is possible to prevent a decrease in tensile strength and prevent a problem in which flexibility is rather deteriorated due to excessively high bonding strength between the acrylic resin and the cellulose structure after curing.

The acrylic filling composition according to an embodiment of the present invention may include a photoinitiator for curing the acrylic monomer. In this case, the photoinitiator can be used without limitation if it is a conventional photoinitiator used for curing the acrylic. Specifically, the photoinitiator is 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethyl-2,4,6-trimethylbenzoylphenylphosphinate, bis(2,4, One or more materials selected from 6-trimethylbenzoyl)-phenylphosphine oxide and 2-hydroxy-2-methyl-1-phenyl-propane-1-one, or a commercially available photoinitiator may be used, but the present invention This is not limited thereto. In this case, the photoinitiator may be included in an amount of 0.5 to 2 parts by weight based on the total weight of the acrylic monomer, based on 100 parts by weight of the acrylic monomer, but the present invention is not limited thereto.

The acrylic filling composition according to an embodiment of the present invention may further include conventional additives such as an antifoaming agent, a leveling agent, an anti-freezing agent, a UV blocking agent, a dispersing agent, a plasticizer and a preservative in addition to the above-described acrylic monomer.

The dispersing agent can be used without limitation if it is a dispersing agent commonly used in water-based paints, and a commercial dispersant such as BYK's DISPERBYK series is used, or sodium polyacrylate, saponification of styrene maleate anhydride (or olefin) copolymer, Alkylnaphthalene sulfonate sodium-formalin condensate, sodium ligrin sulfonate, polyethylene glycol phenyl ether, and a compound such as sodium polycarbonate salt may be used, but the present invention is not limited thereto. The dispersant may be included in an amount of 0.5 to 5 parts by weight, preferably 1 to 3 parts by weight, based on 100 parts by weight of the acrylic monomer.

The anti-foaming agent can be used without limitation if it is an anti-foaming agent commonly used in the paint field. The antifoaming agent may be included in an amount of 0.1 to 3 parts by weight based on 100 parts by weight of the acrylic emulsion, and in this range, it is possible to effectively remove air bubbles while preventing the problem of deterioration of the smoothness of the coating film.

When the acrylic filling composition is prepared by mixing a two-component main agent and a curing agent in the acrylic transparent wood manufacturing method according to an embodiment of the present invention, the subject may further include a solvent for viscosity control in addition to the acrylic resin. there is. In this case, the solvent is not limited in the case of an organic solvent capable of lowering the viscosity of the acrylic filling composition, but preferably acetone or the like may be used. Specifically, the acrylic filling composition may contain 20 to 50 parts by weight of a solvent relative to 100 parts by weight of the acrylic resin, and when the solvent is too little, it is difficult to uniformly fill the acrylic resin in the cellulose structure, and when the solvent is too much, the curing time This delay can cause problems.

In the method for producing transparent acrylic wood according to an embodiment of the present invention, the weight ratio of wood: acrylic resin in transparent acrylic wood may be 1:3 to 7, more specifically, 1:4 to 6, in which a small amount of acrylic resin is added. In this case, the acrylic filling composition is not sufficiently filled between the cellulose structures, which may cause a decrease in mechanical strength and transparency.

In the transparent acrylic wood manufacturing method according to an embodiment of the present invention, the transparent acrylic wood may have a tensile strength of 17 MPa or more, specifically, 17 to 20 MPa. Furthermore, in the method for manufacturing transparent acrylic wood according to an embodiment of the present invention, the wood can be used without limitation in the case of commonly referred to as wood, but preferably balsa wood (Ochroma pyramidale) can be used, and balsa wood can be used. When using acrylic transparent wood, it has the advantage that it can be applied to various fields because it is light in weight while exhibiting physical properties such as high tensile strength. In addition, while satisfying the above-described tensile strength range, the flexural strength can satisfy 25 to 35 MPa, which means that the produced acrylic transparent wood exhibits flexibility above a certain level, but does not show a significant decrease in mechanical strength. can

The present invention also provides a transparent acrylic wood, and the transparent acrylic wood according to the present invention may be manufactured by the manufacturing method according to an embodiment of the present invention. The manufactured acrylic transparent wood has mechanical strength such as excellent light transmittance and tensile strength, and has the advantage of being able to replace glass in various fields.

Hereinafter, the present invention will be specifically described by way of Examples and Comparative Examples. The examples below are only for helping understanding of the present invention, and the scope of the present invention is not limited by the examples below.

[Production Example 1]

1. Removal of lignin

A piece of Balsa wood having a width × length × thickness of 3 cm × 7 cm × 0.5 cm was prepared and dried in an oven at 80° C. for 24 hours. The dried pieces of Balsa wood _{were immersed in a boiling aqueous solution containing NaOH (2.5} mol/L) and Na 2 SO ₃ (0.4 mol/L), left for 36 hours, and washed three times with distilled water. After that, the wood is impregnated in a boiling solution having a ratio of hydrogen peroxide: distilled water of 1:3 for 1 hour, washed with cold water, washed with ethanol three times, and dried to remove the lignin and the cellulose structure is left. , the weight was measured.

2. Addition of acrylic resin

After mixing 30 g of acetone with 38.7 g of 2-hydroxyethyl methacrylate (monomer 1), 61.3 g of phenoxyethyl methacrylate (monomer 2) was added and stirred for 1 hour with a stirrer. Then, 1 g of BYK's Disperbyk-163 as a dispersant, 0.5 g of Evonik's TEGO Airex 920 as an antifoaming agent, and 1 g of 2-hydroxy-2-methyl-1-phenyl-1-one as a photoinitiator were sequentially mixed to form acryl A filling composition was prepared.

After putting the wood in a mold suitable for the size of the remaining wood with the cellulose structure, a mixed solution of the main agent and the curing agent was injected, and the acrylic filling composition was cured by UV irradiation. It was confirmed that the weight ratio of the wood with the cellulose structure remaining after curing: the added acrylic filling composition was 1:5.

In addition, the prepared transparent wood was observed by SEM and the results are shown in FIG. 1 , and referring to FIG. 1 , it was confirmed that the acrylic resin was filled between the cellulose structures.

[Preparation Examples 2 to 10]

It was prepared in the same manner as in Preparation Example 1, except that the conditions were changed as shown in Table 1 to prepare transparent wood.

manufacturing example lignin removal Acrylic Filling Composition Acrylic transparent wood Hydrogen Peroxide: Distilled Water Ratio Monomer 1 (g) Monomer 2 (g) Wood: Acrylic Resin Ratio One 1:3 38.7 61.3 1:5 2 1:3.5 38.7 61.3 1:5 3 1:1 38.7 61.3 1:5 4 1:5 38.7 61.3 1:5 5 1:3 38.7 40 1:5 6 1:3 38.7 90 1:5 7 1:3 100 0 1:5 8 1:3 0 100 1:5 9 1:3 38.7 61.3 1:2.5 10 1:3 38.7 61.3 1:8

Measurement of Tensile Strength of Manufactured Transparent Wood

The tensile strengths of the transparent wood and dried balsa wood prepared in Preparation Example were measured, respectively, and the results are shown in Table 2.

Transparency measurement of manufactured transparent wood

The average light transmittance was measured by UV-vis in the wavelength range of 300 to 800 nm of the transparent wood prepared in Preparation Example, and the results are shown in Table 2.

Tensile strength (MPa) Tensile strain (%) Light transmittance (%) Preparation Example 1 17.1 2.4 84 Preparation 2 17.2 2.3 83 Preparation 3 16.1 1.3 81 Preparation 4 16.9 1.1 59 Preparation 5 17.0 1.6 75 Preparation 6 16.5 1.8 73 Preparation 7 16.3 1.9 76 Preparation 8 16.4 1.7 74 Preparation 9 16.2 0.5 56 Preparation 10 16.4 0.7 81 balsa wood 16.0 0.002 -

Referring to Table 2, it can be seen that the tensile strength of the transparent wood prepared in Preparation Examples 1 and 2 is the highest, and the tensile strain is also the best. In the case of adding excessive hydrogen peroxide in the hydrogen peroxide treatment step of wood, a decrease in tensile strength and tensile strain occurs due to partial damage to the cellulose structure. can In addition, in the case of Preparation Examples 5 to 8 in which the ratio of Monomer 1 and Monomer 2 exceeds the appropriate range, or in which only Monomer 1 or Monomer 2 is added, the binding force with the cellulose structure by the hydroxyacrylic monomer is insufficient, or the binding force is too high. It can be confirmed that the tensile strain and tensile strength are lowered. In the case of Preparation Example 9 containing a small amount of acrylic resin, the acrylic resin is not sufficiently filled between the cellulose structures, which not only causes deterioration of physical properties, but also causes a significant decrease in light transmittance. There is a problem in that it is difficult to show improvement in physical properties compared to the case where only the resin is cured.

Confirmation of flexural strength of manufactured transparent wood

The flexural strength of the specimen prepared in Preparation Example 1 and the acrylic specimen prepared in the same manner as in Preparation Example 1, but prepared by curing only the acrylic resin without the cellulose structure, were measured, respectively, and the results are shown in Table 2.

The measured specimen was measured with a universal testing machine using a specimen having a length of 100 mm, a width of 10 mm, and a thickness of 3 mm.

Preparation Example 1 acrylic specimen Flexural strength (MPa) 29 41

Referring to the results in Table 3, it can be confirmed that the flexural strength of the acrylic transparent wood evacuated from the acrylic specimen is low, and through this, it can be confirmed that the flexibility of the acrylic transparent wood is improved compared to the specimen made of only acrylic.

Claims (13)

A first step of treating the wood with a treatment solution containing a base and a sulfite;
a second step of treating the treated wood with the treatment solution with hydrogen peroxide;
a third step of impregnating the treated wood with the hydrogen peroxide water in an acrylic filling composition; and
A fourth step of curing the acrylic filling composition;
The acrylic filling composition includes a hydroxy acrylic monomer including a hydroxy group and a high refractive acrylic monomer,
The high refractive acrylic monomer includes one or two or more selected from phenoxyethyl methacrylate, phenoxy-2-methylethyl methacrylate, phenoxyethoxyethyl methacrylate and phenoxyethoxyethyl acrylate,
The hydroxy acrylic monomer: the molar ratio of the high refractive monomer is 1:0.8 to 1.2,
A method of manufacturing transparent acrylic wood, characterized in that the tensile strength is 17 MPa or more and the light transmittance is 80% or more. The method of claim 1,
The method for producing transparent acrylic wood, characterized in that the weight ratio of hydrogen peroxide: water contained in the hydrogen peroxide solution is 1:1 to 5. The method of claim 1,
In the transparent acrylic wood, the weight ratio of wood: acrylic resin is 1:3 to 7, characterized in that the acrylic transparent wood manufacturing method. The method of claim 1,
The molar ratio of the sulfite to the base is 1:3 to 10. A method for producing a transparent acrylic wood. The method of claim 1,
The first step is an acrylic transparent wood manufacturing method that is performed for 1 to 60 hours. The method of claim 1,
The method for producing transparent acrylic wood further comprising a washing step of removing base and salt from the wood after the first step and before the second step. The method of claim 1,
The second step is an acrylic transparent wood manufacturing method performed for 10 to 120 minutes. The method of claim 1,
The acrylic transparent wood manufacturing method, characterized in that the light transmittance is 80% or more in a wavelength range of 300 to 800 nm. delete delete The method of claim 1,
The hydroxy acrylic monomer is acryl containing one or two or more selected from 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate. Transparent wood manufacturing method. delete An acrylic transparent wood manufactured by the manufacturing method of any one of claims 1 to 8 and 11.

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