JP2636068B2 - Oligoesterified wood material composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides a method for plasticizing a wood material component in hot-pressing, which can be easily formed without discoloration due to thermal degradation, and which has a dense and glossy product. The present invention relates to an oligoesterified wood material composition which has a certain surface and is industrially advantageous in obtaining an inexpensive plastic-like wood-based molded product having excellent physical properties such as thermal stability.

(Prior Art) Wood has been used more frequently for building materials and other various applications by utilizing its excellent properties. However, it has no thermoplasticity due to its characteristics, and there is a problem in manufacturing a molded product. From such a viewpoint, recently, researches have been conducted to impart functions that wood originally does not have, such as thermoplasticity, by applying appropriate chemical modification to wood.

These studies are based on the chemical reaction of hydroxyl groups in wood.
By introducing an organic group, wood is given a thermoplastic property that it does not originally possess, and it is intended to mold and process the wood itself.It is not only used for new materials, but also for small diameter trees and thinned wood. It is extremely important from the viewpoint of effective utilization of unused wood resources.

The present inventors have previously added a dibasic acid anhydride and monoepoxide to wood chips and allowed them to undergo an addition esterification reaction,
Or a modification characterized by adding a monoepoxide or a monoepoxide and a diacid anhydride to a carboxyl group-containing esterified wood piece obtained by adding a dibasic acid anhydride to a hydroxyl group in wood to cause an addition esterification reaction. A method for producing wood chips (Japanese Patent Application No. 60-83806) was proposed.

However, although the molded article made of the modified wood pieces obtained by the above method is excellent in performance such as weather resistance, the modified wood pieces using epichlorohydrin as the monoepoxide are inexpensive, but discolored at the time of hot pressing. However, there was a problem of blackening.

(Problems to be Solved by the Invention) The present inventors have found that one of the constituents in an oligoesterified wood material in which a polybasic acid anhydride and a monoepoxy compound are alternately added to a hydroxyl group in the wood material component. While using very inexpensive epichlorohydrin for the monoepoxy compound, the wood material component is plasticized during hot pressing and molding can be easily performed, and there is no discoloration due to thermal deterioration, and the molded product is dense and glossy A composition for obtaining an inexpensive plastic-like wood-based molded product having a firm surface and particularly excellent physical properties such as thermal stability was studied.

(Means for Solving the Problems) As a result of repeated studies in view of the above-described circumstances, the present inventors have found that a monobasic acid anhydride and an epichlorohydrin or at least an epichlorohydrin-containing monobasic acid anhydride are contained in a hydroxyl group in a wood material component. Oligoesterified wood material in which one or more selected from organic acid salts, inorganic acid salts and organic tin compounds (hereinafter referred to as stabilizers) are blended with oligoesterified wood material to which epoxy compounds are alternately added. The product can be easily molded without discoloration due to thermal degradation during hot-press molding, while using epichlorohydrin, which is very inexpensive as a monoepoxy compound. It has been found that a plastic-like wood-based molded product with a glossy surface and excellent physical properties such as thermal stability can be obtained economically advantageously. Ming has been reached.

That is, the present invention provides an oligoesterified wood material composition comprising an oligoesterified wood material and a stabilizer in which a polybasic anhydride and epichlorohydrin or a monoepoxy compound containing at least epichlorohydrin are alternately added to hydroxyl groups in the wood material component. It provides things.

The oligoesterified wood material used in the present invention is a method of (1) alternately adding a polybasic acid anhydride and epichlorohydrin or a monoepoxy compound containing at least epichlorohydrin to a hydroxyl group in the wood material component.

(2) a carboxyl group-containing esterified wood obtained by adding a polybasic anhydride to a hydroxyl group in a wood material component, a monoepoxy compound containing epichlorohydrin or at least epichlorohydrin, or a monoepoxy compound containing epichlorohydrin or at least epichlorohydrin; It can be produced by a method in which a polybasic acid anhydride is added to cause an oligoesterification reaction.

The reaction product obtained by the above reaction contains, as a by-product, an oligomer (hereinafter, referred to as an oligomer) composed of a polybasic acid anhydride and epichlorohydrin or a polybasic acid anhydride and a monoepoxy compound. Of polybasic acid anhydrides, epichlorohydrin and monoepoxy compounds (hereinafter referred to as unreacted monomers). In the present invention, together with the oligoesterified wood material,
The presence of the oligomer and the unreacted monomer does not cause any problem, and the reaction product formed by the above reaction may be used as an oligoesterified wood material extruded with a solvent to remove the oligomer and the unreacted monomer, After the reaction, the obtained reaction products (including oligoesterified wood and oligomers and unreacted monomers)
May be used as is.

In the production of oligoesterified wood, wood materials such as wood flour, wood fiber, wood chips and the like are mainly used, and there are no particular restrictions on the raw wood and tree species. The woody materials in the present invention also include those obtained by pulverizing plant fibers such as straw and firgrass and other lignocellulosic materials containing cellulose or cellulose or lignin as a main component. In addition, particle board,
Sander powder or the like discharged during the manufacturing process of fiberboard or the like can also be used.

Examples of the polybasic acid anhydride include phthalic anhydride, maleic anhydride, succinic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, itaconic anhydride, hetanoic anhydride, pyromellitic anhydride and the like. Particularly, industrially advantageous and inexpensive phthalic anhydride, maleic anhydride, succinic anhydride, and the like are preferable. Among them, phthalic anhydride is preferable because the wood material composition of the present invention has excellent heat stability.

Epoxy compounds that can be used in combination with epichlorohydrin include, for example, allyl glycidyl ether, methyl glycidyl ether, butyl glycidyl ether, phenyl glycidyl ether, styrene oxide, glycidyl methacrylate, and the like. The mixing ratio of epichlorohydrin and other epoxy compounds is preferably other than 1000 parts by weight with respect to 100 parts by weight of epichlorohydrin.

The stabilizer used in the present invention is an organic acid salt, an inorganic acid salt or an organic tin compound.

Organic salts include carboxylate, organic phosphate, and organic phosphite. Examples of the carboxylate include lithium stearate, lithium oxystearate, lithium acetate, sodium stearate, magnesium stearate, and stearate. Aluminum phosphate, calcium stearate, calcium laurate, calcium 2-ethylhexylate, calcium ricinoleate, calcium ethyl acetoacetate, strontium stearate, barium stearate, barium acetate, barium laurate, 2-
Barium ethylhexylate, barium ricinoleate, zinc stearate, zinc laurate, zinc 2-ethylhexylate, cadmium stearate, cadmium laurate, cadmium 2-ethylhexylate, cadmium ricinoleate, cadmium naphthenate, lead stearate, basic Examples include lead stearate, dibasic lead stearate, 2-ethylhexyl lead, lead naphthenate, tribasic lead maleate, dibasic lead phthalate, and salicylate.

Examples of the organic phosphate include sodium methyl phosphate and barium ethyl phosphate.

Organic phosphites include barium ethyl phosphite,
Cadmium ethyl phosphite and the like can be mentioned.

Inorganic acid salts include inorganic phosphates and phosphites, silicates, sulfates and sulfites, carbonates,
Inorganic phosphates and phosphites include cadmium phosphate and dibasic lead phosphite, and silicates include lead orthosilicate and basic lead silicate such as sulfur salts and sulfites. Examples thereof include tribasic lead sulfate and basic lead sulfite, and examples of the carbonate include basic lead carbonate, zinc carbonate, and cadmium carbonate.

Examples of the organotin compound include dibutyltin dilaurate, dibutyltin distearate, dibutyltin dinonylate, tribenzyltin laurate, dibutyltin malate and the like. Among them, basic lead carbonate, tribasic lead sulfate, cadmium carbonate, cadmium ethyl phosphite, and barium stearate are preferred. These stabilizers can be used alone or in combination of two or more. In addition, phenol, benzophenone-based compounds, and epoxy compounds that react with HCl, which usually supplement radicals, have no effect as stabilizers.

The oligoesterified wood material composition of the present invention may comprise one or two or more stabilizers selected from organic acid salts, inorganic acid salts and organic tin compounds added to the oligoesterified wood material prepared as described above. The mixing ratio of the oligoesterified wood material and the stabilizer is preferably 0.5 to 20 parts by weight based on 100 parts by weight of the oligoesterified wood material. In particular, 0.5 parts by weight or more is effective for discoloration due to thermal deterioration, and 20 parts by weight or less is economically advantageous. Further, at the time of mixing, other fillers and plasticizers may be added. The method for obtaining such a mixture is not particularly limited. For example, the oligoesterified wood material composition of the present invention can be formed using a kneader such as a blender, kneader, mixing roll, or Banbury mixer.

The oligoesterified wood material composition obtained in the present invention is formed into a molding die and hot-pressed at 120 to 200 ° C. to obtain a plastic-like wood-based molded product. If the heating temperature is lower than 120 ° C., the wood material component in the oligoesterified wood material is not plasticized, and if it exceeds 200 ° C., thermal decomposition of the oligoesterified wood material occurs, which is not preferable. The pressure may be the pressure required for the oligoesterified wood to plasticize at these temperatures, typically between 30 and 60.
A 0kg · f / cm ^2, preferably 50~500kg · f / cm ^2. The heating time is preferably 0.5 to 40 minutes. In the oligoesterified wood composition of the present invention, plasticization of the wood material component occurs under these hot pressure conditions, and a molded article is obtained.At the time of hot pressing, the stabilizer is epichlorohydrin added to the wood material. Since chlorine, which is considered to be a cause of thermal degradation released from the steel, can be caught, discoloration during hot pressing can be suppressed, and a molded article having a good appearance can be obtained. In the present invention, a good molded product can be obtained even in a mold having a very complicated shape. Further, the oligoesterified wood material composition of the present invention can be used for the flowability of wood material components by hot pressure. Because of this, molding by transfer molding or injection molding is possible.

(Examples) Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but it goes without saying that the present invention is not limited to these Examples. The thermal degradation of the sheet obtained by hot pressing from the oligoesterified wood and the stabilizer was evaluated by visual inspection and direct reading of the stimulus value (ND-101DP colorimeter, Nippon Denshoku Industries Co., Ltd.). )), L, a, b and ΔE determined from the tristimulus values XYZ were measured and shown in the table.

The larger the value of L, the higher the brightness and the higher the brightness,
In the case of a, the degree of red increases as the numerical value increases in the + side, the degree of green increases in the-side, and the degree of yellow increases in the + side, and the degree of blue increases in the-side. Indicates that the smaller the is, the greater the whiteness is.

Production Example 1 Wood flour (trade name: LIGNOCEL S150TR; J. Rettenmaier & Soeh
ne company; fiber length; 30-60μ) 90 g, phthalic anhydride 33.0 g,
27.0 g of epichlorohydrin was charged into one three-neck separable flask and reacted at 120 ° C. for 6 hours with stirring to react with 109.8 g of oligoesterified wood material, 35.6 g of oligomer, 2.9 g of phthalic anhydride and 1.7 g of oligochlorohydrin. A reaction product containing an esterified wood material as a main component was obtained. The amount of phthalic anhydride and epichlorohydrin added to the wood material of this oligoesterified wood material was 22% based on the wood material.

Production Example 2 Wood flour (Product name: LIGNOCEL S150TR; J. Rettenmaier & Soeh
ne company; fiber length; 30-60μ) 90 g, maleic anhydride 27.0
g, 0.945 g of sodium carbonate as a catalyst was charged into a one-necked separable flask and reacted at 120 ° C. for 6 hours with stirring to obtain a reaction product comprising a carboxyl group-containing esterified wood material and unreacted maleic anhydride. I got next,
100 g of the carboxyl group-containing esterified wood material and 28.0 g of epichlorohydrin were charged into one three-neck separable flask and reacted with stirring at 120 ° C. for 6 hours, and 113.8 g of oligoesterified wood material and 11.7 g of oligomer, 11.7 g of maleic anhydride, A reaction product composed mainly of oligoesterified wood material consisting of 0.5 g of acid and 2.0 g of epichlorohydrin was obtained. The amount of maleic anhydride and epichlorohydrin added to the wood material of this oligoesterified wood material was 48% based on the wood material.

Production Example 3 90 g of red pine wood flour, 15 g of succinic anhydride, and 0.945 g of sodium carbonate were charged into a three-neck separable flask through a 24-mesh sieve, and reacted at 120 ° C. for 6 hours with stirring. A reaction product consisting of carboxyl group-containing esterified wood and unreacted succinic anhydride was obtained. Next, 100 g of this carboxyl group-containing esterified wood, succinic anhydride
11.5 g and 31.0 g of epichlorohydrin were charged into one three-neck separable flask, reacted at 120 ° C. for 6 hours with stirring, and then oligomers and unreacted monomers were sufficiently extracted with an acetone solvent and dried to obtain oligoesterified wood. 115.5 g were obtained. The amount of epichlorohydrin and succinic anhydride added to the wood material of this oligoesterified wood material was 36% based on the wood material.

Production Example 4 90 g of fir powder, 33.0 g of phthalic anhydride and 27.0 g of epichlorohydrin that had passed through a 24-mesh sieve were charged into one three-neck separable flask, reacted at 120 ° C. for 6 hours with stirring, and then reacted with an acetone solvent. The oligomer and unreacted monomer were sufficiently extracted and dried to obtain 112.5 g of an oligoesterified wood material. The amount of succinic anhydride and epichlorohydrin added to the wood material of this oligoesterified wood material was 25% based on the wood material.

Examples 1 to 5 Stabilizers (barium stearate, lead stearate, sodium stearate, aluminum stearate, basic lead carbonate, etc.) were added to the reaction product containing the oligoesterified wood material obtained in Production Example 1 as a main component. ) Were mixed and stirred at the composition ratios shown in Table 1 to obtain an oligoesterified wood material composition of the present invention. This oligoesterified wood material composition was hot-pressed at 140 ° C., 300 kg · f / cm ² for 30 minutes using a hot press to obtain a sheet having a thickness of 0.4 mm and excellent surface smoothness. .

Comparative Example 1 The reaction product mainly composed of the oligoesterified wood material obtained in Production Example 1 was hot-pressed at 140 ° C., 300 kg · f / cm ² for 30 minutes to obtain a 0.4 mm-thick product. A black sheet was obtained.

Sheets obtained in Examples 1 to 5 and Comparative Example 1 Are shown in Table 1. From these results, Examples 1 to
The oligoesterified wood material composition of the present invention containing the stabilizer of No. 5 has less discoloration due to thermal deterioration during hot pressing than the composition of Comparative Example 1 containing no stabilizer, and the effect of the present invention is it is obvious.

Examples 6 to 9 Stabilizers (basic lead carbonate, cadmium carbonate, barium stearate, zinc carbonate) are shown in Table 2 for the reaction product mainly composed of oligoesterified wood obtained in Production Example 2. The oligoesterified wood material composition of the present invention was obtained by mixing and stirring at the above composition ratio. This oligoesterified wood material composition was hot-pressed at 140 ° C., 300 kg · f / cm ² for 30 minutes to obtain a sheet having a thickness of 0.4 mm and excellent surface smoothness.

Comparative Example 2 The reaction product mainly containing the oligoesterified wood material obtained in Production Example 2 was hot-pressed under the conditions of 140 ° C., 300 kg · f / cm ² , and 30 minutes. A black sheet was obtained.

Sheets obtained in Examples 6 to 9 and Comparative Example 2 Are shown in Table 2. From these results, Examples 6 to
The oligoesterified wood material composition of the present invention containing the stabilizer of No. 9 has less discoloration due to thermal deterioration during hot pressing compared with the composition of Comparative Example 2 containing no stabilizer, and the effect of the present invention is as follows. it is obvious.

Examples 10 to 12 Stabilizers (lithium acetate, dibutyltin malate, lead stearate) were mixed and stirred in the oligoesterified wood obtained in Production Example 3 at the composition ratios shown in Table 3 to obtain the present invention. An oligoesterified wood material composition was obtained. This oligoesterified wood material composition was hot-pressed at 140 ° C., 300 kg · f / cm ² for 30 minutes to obtain a sheet having a thickness of 0.4 mm and excellent surface smoothness.

Comparative Example 3 The oligoesterified wood material obtained in Production Example 3 was mixed with 140
° C., and heat pressure molded under the conditions of 300kg · f / cm ^2, 30 minutes, zero thickness.
A 4 mm black sheet was obtained.

Table 3 shows the color tones of the sheets obtained in Examples 10 to 12 and Comparative Example 3. From these results The oligoesterified wood material composition of the present invention containing the stabilizers of Examples 10 to 12 showed less discoloration due to thermal degradation during hot pressing compared with the composition of Comparative Example 3 containing no stabilizer. The effect of the invention is clear.

Examples 13 to 15 The present invention is obtained by mixing and stirring stabilizers (basic lead carbonate, barium stearate, magnesium stearate) in the composition ratios shown in Table 4 to the oligoesterified wood obtained from Production Example 4. The oligoesterified wood material composition was obtained. This oligoesterified wood material composition, 140 ℃, 300kg · f / cm
^{2. The} sheet was hot-pressed under conditions of 30 minutes to obtain a sheet having a thickness of 0.4 mm and excellent surface smoothness.

Comparative Example 4 The oligoesterified wood material obtained in Production Example 4 was mixed with 140
° C., and heat pressure molded under the conditions of 300kg · f / cm ^2, 30 minutes, zero thickness.
A 4 mm black sheet was obtained.

Table 4 shows the color tones of the sheets obtained in Examples 13 to 15 and Comparative Example 4. From these results The oligoesterified wood material composition of the present invention containing the stabilizers of Examples 13 to 15 showed less discoloration due to thermal deterioration during hot pressing compared with the composition of Comparative Example 4 containing no stabilizer. The effect of the invention is clear.

(Effect of the Invention) As described above, the oligoesterified wood material composition of the present invention uses very inexpensive epichlorohydrin as a monoepoxide, and is therefore extremely economically excellent.
At the time of hot-press molding, at the same time as the wood material component is plasticized, stabilizers such as organic acid salts, inorganic acid salts, and organotin compounds release chlorine from epichlorohydrin and cause chlorine to be discolored. It is excellent and can be easily molded without discoloration due to thermal deterioration. Therefore, the obtained molded product is a homogeneous and beautiful plastic-like despite having a large amount of woody components, and is excellent in various physical properties such as thermal stability. It also retains the good workability inherent to wood materials, such as easy-cutting properties, and is suitable for use in many fields such as building materials, industrial parts materials, and electrical insulating materials. Further, the present invention has an advantage that wood materials and unused water materials can be effectively used as industrial wastes in the water material industry, which is extremely industrially advantageous.

Claims (1)

(57) [Claims] An oligoesterified wood material in which polybasic acid anhydride and epichlorohydrin or at least a monoepoxy compound containing at least epichlorohydrin are alternately added to hydroxyl groups in the wood material component, an organic acid salt, an inorganic acid salt and an organic acid salt. An oligoesterified wood material composition comprising one or more compounds selected from tin compounds.