Composition for manufacturing wood composite comprising kenaf, wood composite using same, and manufacturing method thereof

Abstract

The present invention relates to a composition for manufacturing a wood composite, a wood composite using same, and a manufacturing method thereof. More specifically, the present invention relates to: a composition for manufacturing a wood composite, the composition containing a thermoplastic resin, a silane compound represented by formula (1) and including an acrylate moiety, and a biomass mixture including kenaf powder and wood flour; a wood composite manufactured using same; and a method for manufacturing the wood composite. (In formula (1), R1, R2, and R3 are each independently selected from the group consisting of a C1-6alkoxy, a C1-6alkyl, halogen, a C1-6alkylsiloxy, an allyl, and a C1-6alkenyl; n is 0 to 15; and R4 is a C1-6alkyl.)

Description

Composition for manufacturing wood composite including kenaf, wood composite using same, and method for manufacturing same

[0001] The present invention relates to a composition for manufacturing a wood composite including kenaf, a wood composite using the same, and a method for manufacturing the same, and more particularly, to a composition for manufacturing a wood composite including kenaf having improved mechanical properties, a wood composite using the same, and a method for manufacturing the same.

[0002] Recently, demand for wood-based materials has been increasing in the construction industry due to the preference for the natural texture of wood. However, if wood is used as is, its low resistance to heat, water, and mechanical shock leads to deterioration, deterioration, decay, surface cracking, and damage, making it difficult to maintain its quality. Therefore, wood composites that improve resistance to heat, water, and mechanical shock while maintaining the natural aesthetic and usability of wood have been investigated. Among wood composites, wood-plastic combination, or WPC (abbreviation for Wood-Polymer-Composite), is obtained by impregnating wood with a liquid curable resin or polymerizable monomer and then curing it. It enhances the basic performance by taking advantage of the characteristics of wood, and is therefore widely used in construction materials.

[0003] Meanwhile, wood flour plastic, an eco-friendly, low-carbon new material, is made by combining wood flour, a natural material, with a harmless olefin thermoplastic polymer resin through a special mixing process, making it easy to extrude and injection mold. As a bio-based plastic raw material, it is an eco-friendly material with the advantages of reducing carbon dioxide and being 100% recyclable. It also has the luxurious natural texture of wood and the durability, water resistance, and moldability of polymer resin. However, it has limitations such as carbonization of wood flour due to its low thermal stability during extrusion and injection molding, weakening of the interfacial adhesion between the plastic and wood flour during the cooling process of the molded product, which affects mechanical properties, and decreased preservative properties due to increased moisture content of wood flour due to its hydrophilicity. To overcome these problems, highly toxic chemical additives such as flame retardants, preservatives, and flame retardants are used, which has led to problems such as environmental hormones.

[0004] For example, Korean Patent Publication No. 10-2008-0103734 discloses a biocomposite material with improved mechanical strength, which comprises a biodegradable polymer, a main material made of cellulose-based natural materials, and a hydrolysis inhibitor, but the technology requires the inclusion of a hydrolysis inhibitor such as diisopropyl-phenylisocyanate.

[0005] Meanwhile, kenaf, a natural material, is an annual herbaceous plant of the hibiscus family native to West Africa. It has a high carbon dioxide absorption capacity, contains a lot of useful cellulose, and grows quickly, reaching 3-4 meters in six months, making it a promising plant resource. The kenaf stem can be divided into the bark and the core based on its structure. The bark has a high cellulose content and produces long, strong fibers. For this reason, kenaf fiber has long been used for clothing, bags, ropes, etc. Kenaf varieties around the world are largely divided into early-maturing varieties cultivated in high-latitude regions and late-maturing varieties cultivated in Africa, India, and the United States. While early-maturing varieties can be harvested in Korea's climate, their biomass yield is very low, at around 40-60% of that of late-maturing varieties. Late-maturing varieties have high biomass yields, but cannot be harvested in mid-latitude temperate climates like Korea, making continuous cultivation difficult. To improve this, the Korea Atomic Energy Research Institute developed the medium-late maturing varieties 'Jangdae' and 'Wandae', which can secure more than 80% of the biomass of late maturing varieties while allowing seed collection in the domestic climate by utilizing radiation breeding technology. Currently, the only kenaf varieties developed by the Korea Atomic Energy Research Institute in Korea are 'Jangdae' (National Seed and Variety Service No. 4560), 'Wandae' (National Seed and Variety Service No. 9374), Baekma (National Seed and Variety Service No. 5285), and Jeokbong (National Seed and Variety Service No. 5286), and the 'Wonbaek' variety, which has enhanced salt tolerance and can be cultivated on reclaimed land, has been applied for (National Seed and Variety Service Application No. 2023-72).

[0006] Therefore, if a wood composite material with improved mechanical properties is developed using kenaf without requiring harmful compounds, it is expected to have a wide range of applications.

[0007] One aspect of the present invention is to provide a composition for producing a wood composite from which a wood composite with improved mechanical properties can be obtained.

[0008] Another aspect of the present invention is to provide a wood composite having improved mechanical properties.

[0009] Another aspect of the present invention is to provide a method for producing a wood composite having improved mechanical properties.

[0010] Accordingly, according to one aspect of the present invention, a composition for manufacturing a wood composite is provided, which comprises, based on the weight of the total composition, 10 to 85 wt% of a thermoplastic resin; 0.1 to 20 wt% of a silane compound of the following formula (1) including an acrylate moiety; and 10 to 85 wt% of a biomass mixture including kenaf powder and wood flour.

[0011]

[0012] According to another aspect of the present invention, a wood composite manufactured using the composition for manufacturing a wood composite of the present invention is provided.

[0013] According to another aspect of the present invention, a method for producing a wood composite is provided, comprising the steps of: producing a composition for producing a wood composite by mixing a thermoplastic resin, a silane compound of formula (1) containing an acrylate moiety, and a biomass mixture containing kenaf powder and wood flour; molding the composition for producing a wood composite by heat-extrusion; and irradiating the molded extrudate with electron beams at a dose of 0.1 kGy to 50 kGy.

[0014] According to the present invention, a wood composite material having improved mechanical properties such as tensile strength can be provided using radiation technology.

[0015] Wood composite compound pellets manufactured using the compositions for manufacturing wood composites of Comparative Manufacturing Examples 1 to 3 are shown in Fig. 1(a), and wood composite film samples are shown in Fig. 1(b).

[0016] Figure 2 shows the surface of the wood powder used in Comparative Manufacturing Example 1 and the kenaf (barrel and long bar) powder used in Comparative Manufacturing Examples 2 and 3, as confirmed using a scanning electron microscope.

[0017] Figure 3 shows the melting index, tensile strength, and impact strength of wood composite compound pellets manufactured using the compositions for manufacturing wood composites of Comparative Manufacturing Examples 1 to 3, and the results are shown in Figures 3(a) to 3(c), respectively.

[0018] Figure 4 shows the results of examining the surface of wood composite pellets obtained using the compositions for manufacturing wood composites of Comparative Manufacturing Examples 1 and 3 and Manufacturing Example 2 using a scanning electron microscope.

[0019] Figure 5 shows a manufacturing process of an eco-friendly kenaf wood composite (WPC) including mixing, extrusion and cutting processes and a photograph of a prototype of an eco-friendly wood composite (WPC).

[0020] Figure 6 is a graph showing the change in the physical properties of kenaf composite wood (WPC) according to electron beam irradiation. The left side shows the maximum bending load (N), and the right side shows the impact strength (KJ / m). 2 ) is a graph showing the

[0021] Hereinafter, preferred embodiments of the present invention will be described with reference to the attached drawings. However, the embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below.

[0022] According to the present invention, a composition for manufacturing a wood composite is provided, which can manufacture a wood composite having improved mechanical properties by using radiation technology and applying a combination of specific biomass.

[0023] More specifically, the composition for manufacturing a wood composite of the present invention comprises a thermoplastic resin; a silane compound of the following formula (1) including an acrylate moiety; and a biomass mixture including kenaf powder and wood flour.

[0024]

[0025] The kenaf that can be used in the present invention may be at least one selected from early maturing, medium-late maturing, and late maturing kenaf varieties, preferably a late maturing or medium-late maturing kenaf variety, and may be, for example, a Wandae or Jangdae variety. The Wandae variety can be obtained under the National Seed and Variety Service of Korea's Variety Protection No. 9374, and the Jangdae variety can be obtained under the National Seed and Variety Service's Variety Protection No. 4560, Baekma National Seed and Variety Service No. 5285, Jeokbong National Seed and Variety Service No. 5286, and Wonbaek National Seed and Variety Service Application No. 2023-72.

[0026] Meanwhile, the kenaf may include a core and bark, i.e., a core and bark, and for example, powder obtained from the entire kenaf stem without separating the core and bark may be used.

[0027] The method for producing kenaf powder is not particularly limited, but for example, kenaf powder can be produced by crushing by-products including the core and bark, which are by-products left over from seed oil or nursery cultivation during the kenaf seed fruiting season.

[0028] The present invention utilizes a combination of kenaf powder and wood flour to produce a wood composite material with enhanced tensile strength due to the addition of kenaf powder. This can be interpreted as being due to the porous structure of kenaf, which allows resin components to penetrate into the porous regions, thereby improving physical properties.

[0029] In the above formula (1), R1, R2 and R3 are C 1-6 Alkoxy, C 1-6 Alkyl, halogen, C 1-6 Alkylsiloxy, allyl and C 1-6 are each independently selected from the group consisting of alkenyl; n is 0 to 15; R4 is C 1-6 It's alkyl.

[0030] At this time, the above C 2-6 Alkyl means that it may include cases where unsaturated bonds are present.

[0031] More preferably, R1, R2 and R3 are each independently selected from the group consisting of methoxy, ethoxy, propoxy, butoxy, methyl, ethyl, propyl, butyl, fluoro (F), chloro (Cl), bromo (Br), iodo (I), methylsiloxy, trimethylsiloxy, ethylsiloxy, triethylsiloxy, propylsiloxy, tripropylsiloxy, butylsiloxy, tributylsiloxy, allyl and vinyl; n is 0 to 10; and R4 is methyl, ethyl, propyl or butyl.

[0032] For example, the silane compound of the above formula (1) is, in the above formula (1), R1, R2 and R3 are independently selected from methoxy and ethoxy; n is an integer, for example, 1 to 5; and R4 may be methyl, ethyl or propyl.

[0033] In more detail, the silane compound of the above formula (1) is 3-(trimethoxysilyl)propyl acrylate, 3-(chlorodimethylsilyl)propyl methacrylate, 3-[diethoxy(methyl)silyl]propyl methacrylate, 3-[dimethoxy(methyl)silyl]propyl acrylate, [dimethoxy(methyl)silyl]methyl methacrylate, 3-(trimethoxysilyl)propyl methacrylate, 3-[tris(trimethylsilyloxy)silyl]propyl methacrylate, 3-[dimethoxy(methyl)silyl]propyl methacrylate, 3-(methoxydimethylsilyl)propyl acrylate, 3-(triethoxysilyl)propyl methacrylate, 3-(triallylsilyl)propyl acrylate, 3-(triallylsilyl)propyl methacrylate and It may be at least one selected from the group consisting of (triethoxysilyl)methyl methacrylate.

[0034] The resin of the present invention is preferably thermoformable, and for example, the thermoplastic resin that can be used in the present invention may be at least one selected from the group consisting of polyethylene, polyethylene terephthalate, polyvinyl chloride, polyvinylidene chloride, polystyrene, and polypropylene, but is not limited thereto.

[0035] Furthermore, the thermoplastic resin that can be used in the present invention includes a biodegradable resin. In addition, one or more types of the thermoplastic resins mentioned above and one or more types of the biodegradable resins mentioned below can be mixed and used. The biodegradable resin can be, for example, a bioplastic, and more specifically, a natural polymer made in nature, such as polysaccharide, starch, gum, pectin, natural rubber, lignocellulose, cellulose, hemicellulose, etc.; a bio-based polymer manufactured by polymerizing a biomass-based monomer, such as polylactic acid (PLA), polyglycolic acid (PGA), polyhydroxy alkanoate (PHA); Biodegradable polymers polymerized with petroleum-based monomers include polyhydroxybutyrate (PHB), polycaprolactone (PCL), polybutylene succinate (PBS), poly-β-hydroxybutyrate (PHB), poly-β-hydroxyvalerate (PHV), polybutylene adipate terephthalate (PBAT), polytrimethylene terephthalate (PTT), etc., and the thermoplastic resin of the present invention can use at least one of these.

[0036] Meanwhile, the composition for manufacturing a wood composite of the present invention preferably comprises, based on the weight of the total composition, 10 to 85 wt% of a resin, 0.1 to 20 wt% of a silane compound of the following formula (1) containing an acrylate portion, and 10 to 85 wt% of a biomass mixture containing kenaf powder and wood powder, for example, 10 to 70 wt% of a resin, 0.1 to 10 wt% of a silane compound of the following formula (1) containing an acrylate portion, and 10 to 70 wt% of a biomass mixture containing kenaf powder and wood powder.

[0037] When the resin is less than 10 wt% of the above range, the content of the modified polymer in the composite material is insufficient, resulting in a problem of insufficient mechanical properties. When the content exceeds 85 wt% of the above range, the content of wood powder in the biomass mixture relative to the polymer is insufficient, resulting in a problem of insufficient functioning as a wood composite. On the other hand, when the silane compound of the following formula (1) is less than 0.1 wt% of the above range, there are problems with low mechanical properties and improved hydrophobicity due to crosslinking between the biomass mixture and the polymer. When the content exceeds 20 wt% of the above range, the crosslinking between the biomass mixture and the polymer is too high, resulting in a problem of poor processability during thermal compression molding and injection molding. In addition, when the biomass mixture is less than 10 wt% of the above range, the content of the biomass mixture and / or wood powder relative to the polymer is insufficient, resulting in a problem of insufficient functioning as a wood composite. When the content exceeds 85 wt% of the above range, the content of the polymer in the composite material is insufficient, resulting in a problem of insufficient mechanical properties.

[0038] Furthermore, the composition for manufacturing a wood composite of the present invention may additionally include a bifunctional or trifunctional acrylic monomer. In this case, the trifunctional acrylic monomer has the effect of enhancing crosslinking by increasing the number of double bonds in the acrylic moiety upon irradiation with radiation, thereby increasing the bonding of molecular chains.

[0039] For example, the above-mentioned bifunctional acrylic monomers are 1-(acryloyloxy)-3-(methacryloyloxy)-2-propanol, 1,3-butanediol dimethacrylate, bis(4-methacryloylthiophenyl)sulfide, 1,9-bis(acryloyloxy)nonane, 1,4-bis(acryloyloxy)butane, 1,6-bis(acryloyloxy)hexane, 1,10-bis(acryloyloxy)decane, glycerol dimethacrylate, 1,6-bis(acryloyloxy)-2,2,3,3,4,4,5,5-octafluorohexane, diethylene glycol dimethacrylate, dipropylene glycol diacrylate, 1,12-dodecanediol dimethacrylate, diethylene glycol It may be at least one selected from the group consisting of diacrylate, ditrimethylolpropane tetraacrylate, and ethylene glycol dimethacrylate.

[0040] Meanwhile, the trifunctional acrylic monomer may be at least one selected from the group consisting of 1,6-hexanediol dimethacrylate, 4,4'-isopropylidenediphenol dimethacrylate, neopentyl glycol dimethacrylate, neopentyl glycol diacrylate, nonamethylene glycol dimethacrylate, pentaerythritol tetraacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, triethylene glycol dimethacrylate, trimethylolpropane triacrylate, tetraethylene glycol diacrylate, tris(2-acryloyloxyethyl)isocyanurate, tripropylene glycol diacrylate, tetraethylene glycol dimethacrylate, and tetramethylene glycol dimethacrylate.

[0041] Meanwhile, the thermoplastic resin is included in an amount of 0.4 parts by weight or more and less than 2 parts by weight per 1 part by weight of the biomass mixture, for example, it can be included in a weight ratio of 2:5 to 5:2, or 2:3 to 3:2, and depending on the purpose of injection or extrusion, the thermoplastic resin: biomass mixture can be adjusted to 2:5 or 3:2 to 1:1, or 1:1 to 2:3 or 2:5. However, when the thermoplastic resin is included in an amount of 2 parts by weight or more per 1 part by weight of the biomass mixture, there is a problem in that the manufacturing properties are lowered due to a decrease in the flowability and an increase in unevenness of the mixture during the manufacture of injection and extrusion molded products.

[0042] The above biomass mixture preferably includes wood flour and kenaf powder in a weight ratio of 40:60 to 30:70, and for example, improved tensile strength can be secured in this range.

[0043] Furthermore, according to the present invention, a wood composite manufactured using the composition for manufacturing a wood composite of the present invention described above is provided, and the wood composite of the present invention has improved mechanical properties, and in particular, has improved tensile strength.

[0044] The wood composite of the present invention can be manufactured by the following process.

[0045] More specifically, the method for manufacturing a wood composite of the present invention comprises the steps of providing a composition for manufacturing a wood composite of the present invention described above using kenaf powder; the step of molding the composition for manufacturing a wood composite by heating and extruding it; and the step of irradiating the molded extrudate with electron beams.

[0046] The kenaf powder that can be used in the present invention can be obtained by grinding the core and bark remaining after collecting seeds during the kenaf seed-bearing season to obtain kenaf powder having a mesh size of 90 to 120.

[0047] When kenaf powder is manufactured in this manner, a step of manufacturing a composition for manufacturing a wood composite of the present invention described above is performed by mixing the kenaf powder with a thermoplastic resin, a silane compound of formula (1) containing an acrylate moiety, and a biomass mixture containing kenaf powder and wood powder.

[0048] Subsequently, a step of molding the composition for manufacturing a wood composite by heating and extruding the composition for manufacturing a wood composite is performed.

[0049] The above-mentioned forming step is preferably performed at a temperature range of 170 to 250°C, and more preferably, at a temperature range of 190 to 230°C. If the temperature of the forming step is below the above-mentioned range of 170°C, the forming may not be performed smoothly, and if it exceeds the above-mentioned range of 250°C, there may be a problem of deterioration in the mechanical properties of the wood composite due to thermal decomposition of the polymer resin and carbonization of the wood powder. Meanwhile, the cutting step after forming may be performed after cooling, and for example, cutting, etc. may be performed after cooling to a temperature of 40 to 80°C.

[0050] The step of irradiating the electron beam may be performed at a dose of 0.1 kGy or more and less than 75 kGy, and preferably, the step of irradiating the electron beam is performed at a dose of 0.1 kGy to 50 kGy, for example, at a dose of 1 kGy or more and 25 kGy or less than 25 kGy. If the dose is less than the above range, the improvement in physical properties such as flexural strength may be insufficient, and if it exceeds the above range, the decomposition of the wood composite may occur, thereby reducing physical properties such as flexural strength.

[0051] Furthermore, the step of irradiating the electron beam is preferably performed with an electron beam energy of 1 to 9 MeV, for example, 1 to 5 MeV, more preferably 2 to 3 MeV. If it is below the above range, the improvement in physical properties such as flexural strength may be insufficient, and if it exceeds the above range, the wood composite may decompose, thereby reducing physical properties such as flexural strength.

[0052] Hereinafter, the present invention will be described in more detail through specific examples. The following examples are merely illustrative examples to aid understanding of the present invention and are not intended to limit the scope of the present invention.

[0053] Example

[0054] 1. Preparation of a composition for manufacturing wood composites

[0055] (1) Kenaf powder

[0056] The seeds of Jangdae (National Seed Resources Variety Protection No. 4560) or Wandae (National Seed Resources Variety Protection No. 9374) obtained from the National Seed Resources were collected (used for oil and seedling cultivation) and crushed without separating the remaining core and shell to obtain kenaf powders ranging from 90 to 120 mesh.

[0057] (2) Composition for manufacturing wood composites

[0058] Manufacturing Example 1

[0059] A composition for manufacturing a wood composite was prepared by mixing 9 kg of polyethylene, 0.1 kg of 3-(trimethoxysilyl)propyl methacrylate (hereinafter referred to as 'TMPMA'), and 1 kg of a biomass mixture containing wood powder obtained from Doyle Ecotech Co., Ltd. and the kenaf powder obtained in 1.(1) above at room temperature.

[0060] At this time, a composition for manufacturing a wood composite was manufactured by changing the weight ratio of wood flour and kenaf powder to 100:0, 90:10, 70:30: 50:50, 40:60, 30:70, 10:90, and 0:100.

[0061] Manufacturing Example 2

[0062] A composition for manufacturing a wood composite was manufactured by the same process as Manufacturing Example 1, except that long kenaf powder was used instead of round kenaf powder.

[0063] Comparative Manufacturing Example 1

[0064] A composition for manufacturing a wood composite was manufactured by the same process as Manufacturing Example 1, except that only wood powder was used instead of kenaf powder.

[0065] Comparative Manufacturing Example 2

[0066] A composition for manufacturing a wood composite was manufactured by the same process as Manufacturing Example 1, except that only kenaf powder was used instead of wood flour.

[0067] Comparative manufacturing example 3

[0068] A composition for manufacturing a wood composite was manufactured by the same process as Manufacturing Example 2, except that only long kenaf powder was used instead of wood flour.

[0069] 2. Manufacturing of wood composites

[0070] (1) Manufacturing of wood composite pellets

[0071] The composition for manufacturing a wood composite obtained in the above 1.(2) was cooled to a temperature of 40 to 80°C during a continuous extrusion process at a temperature of 190°C using a mixer (Brabender, Lab-station), cut into pieces with a length of 2 mm to 6 mm and a diameter of 2 mm to 4 mm, and extruded into cylindrical master batch pellets of about 5 mm in length, and then irradiated with electron beams of 10 kGy using an electron beam accelerator (2.5 MeV) to obtain a wood composite.

[0072] The wood composite compound pellet thus obtained is shown in Fig. 1(a).

[0073] (2) Preparation of wood composite film samples

[0074] The composition for manufacturing wood composite obtained in the above 1.(2) was melt-mixed using a batch-type melt mixer equipped with a roller blade rotor (HAAKE PolyDrive Rheomix 600, Thermo Electron Corporation, Germany), and then heat-compressed using a hydraulic heat compression molding machine at a temperature of 185°C and a pressure of 3000 psi for 4 minutes to produce a film (sheet)-shaped sample, and then irradiated with electron beams of 10 kGy using an electron beam accelerator (2.5 MeV).

[0075] A sample of the wood composite film thus obtained is shown in Fig. 1(b).

[0076] 3. Confirmation of the physical properties of wood composites

[0077] (1) Surface analysis

[0078] 1) Surface analysis of wood flour and kenaf powder

[0079] The surfaces of wood powder and kenaf powder were examined using a scanning electron microscope, and as a result, as can be seen in Fig. 2, the surface analysis of wood powder (wood powder) and kenaf powder showed that wood powder had a smooth surface, whereas the surface of kenaf powder showed a rough surface due to the broken walls of the conduit, and it was confirmed that the physical properties could be improved due to the structural difference between the surfaces when melt-mixed with a polymer.

[0080] 2) Surface analysis of wood composites

[0081] The surface of the wood composite pellets obtained using the compositions for manufacturing wood composites of Manufacturing Example 2 and Comparative Manufacturing Examples 1 and 3, in which the weight ratio of wood flour and kenaf (rod) powder was 30:70, was examined using a scanning electron microscope, and the results are shown in Fig. 4.

[0082] As can be seen in Fig. 4, when kenaf powder is included, components such as resin are introduced into the porous structure, which can improve adhesive strength and physical properties. Therefore, when a mixture of wood powder and kenaf is applied, the physical properties complement each other, which can be more desirable.

[0083] (2) Property evaluation

[0084] 1) Melting index

[0085] After heating the cylinder bore to 210℃, the material is then placed in the cylinder, the piston to apply the load is placed in position, and after 5 minutes, the discharge amount from the orifice is cut off, and after 1 minute again, the discharge speed is calculated as g / 10 min.

[0086] 2) Tensile strength

[0087] Tested according to ASTM D638, using a UTM (Universal testing machine), the test evaluates the basic mechanical properties (tensile strength, elongation, elastic modulus) of the material. When a dumbbell-shaped tensile specimen is fixed to both cranes and pulled at a constant speed, the SS curve and the tensile strength, elongation, and elastic modulus values ​​obtained during stress deformation are measured.

[0088] 3) Impact strength

[0089] Tested according to ASTM D256, the Izod impact test is a test that measures the resistance when a high-speed load is applied to a body. One end of a standard bending specimen is fixed and the other end is struck with a hammer in the direction of the notch to destroy it, and the impact value is measured.

[0090] The melt index, tensile strength, and impact strength of wood composite compound pellets manufactured using the compositions for manufacturing wood composites of Comparative Manufacturing Examples 1 to 3 were respectively checked by each of the above evaluation methods, and the results are shown in Figs. 3(a) to 3(c), respectively. As a result, it was confirmed that the physical properties were further improved when using kenaf powder.

[0091] Meanwhile, the tensile strength of the 2.(2) wood composite film samples manufactured using the wood flour and long kenaf powder of Manufacturing Example 2 was compared with the case where electron beam was not irradiated as a control group while changing the weight ratio of wood flour and kenaf powder to 100:0, 90:10, 70:30: 50:50, 40:60, 30:70, 10:90, and 0:100. The results are shown in Table 1 below.

[0092] [Table 1]

[0093]

[0094] As a result, it was confirmed that the tensile strength was significantly increased when electron beam was irradiated, and in particular, the tensile strength was excellent when the weight ratio of wood flour:kenaf was 40:60 to 30:70.

[0095] 4. Production of eco-friendly kenaf wood composite (WPC) prototypes and verification of their properties.

[0096] (1) Manufacturing of wood composite (WPC)

[0097] An eco-friendly synthetic wood (WPC) containing 29.7 wt% polyethylene, 0.3 wt% 3-(trimethoxysilyl)propyl methacrylate (hereinafter referred to as 'TMPMA'), 60 wt% wood flour, and 10 wt% long kenaf biomass powder was manufactured through a mixing, extrusion, and cutting process as shown in Fig. 5. The synthetic wood manufactured in this manner was irradiated with electron beams at a total irradiation dose of 20 kGy, and an official test was performed to confirm the quality suitability of the kenaf synthetic wood irradiated in this manner.

[0098] At this time, the test method was conducted according to KS F 3230:2020, and the results are as shown in Table 2 below.

[0099] [Table 2] Quality suitability test results for kenaf wood composite (WPC)

[0100]

[0101] As can be seen in Table 2 above, the synthetic wood manufactured using kenaf according to the present invention was confirmed to have physical properties such as impact strength, maximum flexural load, flexural creep deformation, impact resistance (room temperature / low temperature), warpage, screw holding power, slip resistance (CSR), moisture absorption rate (weight change), freeze-thaw (maximum flexural load change rate), linear thermal expansion coefficient, flame retardancy, and specific gravity that are suitable as synthetic wood, and formaldehyde emissions and hazardous heavy metals such as arsenic, cadmium, chromium, lead, and mercury were not detected, confirming that it is chemically safe.

[0102] (2) Confirmation of physical properties of wood composite (WPC)

[0103] In order to improve the properties of the synthetic wood of the present invention including kenaf, the synthetic wood was irradiated with electron beams (20 kGy) to analyze the change in physical strength, and the results are shown in Fig. 6. As a result, as can be confirmed in Fig. 6, the maximum bending load (N) of the kenaf synthetic wood increased by about 7% from 3,465 to 3,715 by electron beam irradiation, and the impact strength (KJ / m 2 ) increased by approximately 6% from 3.3 to 3.5, indicating that electron beam irradiation improved the physical properties of synthetic wood.

[0104] Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and it will be apparent to those skilled in the art that various modifications and variations are possible within a scope that does not depart from the technical spirit of the present invention described in the claims.

Claims

1. Based on the weight of the entire composition, 10 to 85 wt% of thermoplastic resin; 0.1 to 20 wt% of a silane compound of the following formula (1) containing an acrylate moiety; and 10 to 85 wt% of a biomass mixture comprising kenaf powder and wood flour Composition for manufacturing wood composite, comprising: In the above formula (1), R1, R2 and R3 are C 1-6 Alkoxy, C 1-6 Alkyl, Halogen, C 1-6 Alkylsiloxy, allyl and C 1-6 Each independently selected from the group consisting of alkenyl; n is 0 to 15; R4 is C 1-6 It's alkyl.

2. A composition for manufacturing a wood composite material, wherein the thermoplastic resin is contained in an amount of 0.4 to 2 parts by weight per 1 part by weight of the biomass mixture in the first paragraph.

3. A composition for manufacturing a wood composite material, wherein the biomass mixture in paragraph 1 contains wood flour and kenaf powder in a weight ratio of 40:60 to 30:

70.

4. In the first paragraph, the kenaf is at least one selected from the group consisting of long-leaved maple (National Seed Resources No. 4560), long-leaved maple (National Seed Resources No. 9374), white maple (National Seed Resources No. 5285), red maple (National Seed Resources No. 5286), and white maple (National Seed Resources Application No. 2023-72). A composition for manufacturing a wood composite material.

5. A composition for manufacturing a wood composite material, wherein the kenaf comprises a core and a shell in the first paragraph.

6. A composition for manufacturing a wood composite material, wherein the thermoplastic resin in paragraph 1 is at least one selected from the group consisting of polyethylene, polyethylene terephthalate, polyvinyl chloride, polyvinylidene chloride, polystyrene, and polypropylene.

7. In the first paragraph, the silane compound of the formula (1) is a composition for producing a wood composite, wherein in the formula (1), R1, R2 and R3 are independently selected from methoxy and ethoxy; n is 1 to 5; and R4 is methyl, ethyl or propyl.

8. In the first paragraph, the silane compound of the formula (1) is 3-(trimethoxysilyl)propyl acrylate, 3-(chlorodimethylsilyl)propyl methacrylate, 3-[diethoxy(methyl)silyl]propyl methacrylate, 3-[dimethoxy(methyl)silyl]propyl acrylate, [dimethoxy(methyl)silyl]methyl methacrylate, 3-(trimethoxysilyl)propyl methacrylate, 3-[tris(trimethylsilyloxy)silyl]propyl methacrylate, 3-[dimethoxy(methyl)silyl]propyl methacrylate, 3-(methoxydimethylsilyl)propyl acrylate, 3-(triethoxysilyl)propyl methacrylate, 3-(triallylsilyl)propyl acrylate, 3-(triallylsilyl)propyl methacrylate and A composition for producing a wood composite, wherein the composition comprises at least one selected from the group consisting of (triethoxysilyl) methyl methacrylate.

9. A composition for producing a wood composite, further comprising a bifunctional or trifunctional acrylic monomer in the first paragraph.

10. A step of producing a composition for producing a wood composite according to any one of claims 1 to 9 by mixing a thermoplastic resin, a silane compound of formula (1) including an acrylate moiety, and a biomass mixture including kenaf powder and wood flour; A step of molding the composition for manufacturing the above wood composite by heating and extruding; and A step of irradiating the molded extrudate with electron beams at a dose of 0.1 kGy to 50 kGy. A method for manufacturing a wood composite comprising:

11. A method for manufacturing a wood composite material in claim 10, wherein the forming step is performed at a temperature range of 170 to 250°C.

12. A method for manufacturing a wood composite, wherein the step of irradiating the electron beam in the 10th paragraph is performed with an electron beam energy of 1 to 9 MeV.

13. A wood composite manufactured by irradiating a heated extrusion molded product of the composition for manufacturing a wood composite according to any one of claims 1 to 9 with electron beams at a dose of 0.1 kGy or more and less than 75 kGy.

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