JPH0337486B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to the thermochemical modification of wood for use in the manufacture of ski edges, substrates, or other products where it is necessary to improve the physical and mechanical properties or weather resistance of the wood. More particularly, the present invention relates to an impregnating composition suitable for thermochemical modification of wood and a method for producing the composition. Currently, low-molecular, oligomeric, and polymeric substances are available with various properties that can improve the physical and mechanical properties, biological resistance, water resistance, chemical resistance, and other properties of wood, depending on the application. I'm starting to be able to do it. The weatherability of wood can be improved by adding small amounts of certain phenols and other toxic compounds. For example, US Pat. No. 3,995,077 describes the use of polychlorophenol, nitrophenol, chloronaphthalene, and zinc oxide, butyltin, and copper compounds dissolved in a petroleum-based solvent as preservatives. West German Patent No. 2555984 suggests the use of polyphenols in combination with quinolines and thiophosphate compounds. US Pat. No. 4,013,804 describes that a polychlorophenol composition is modified with a polyester of a polyhydric alcohol or a paraffin wax. British Patent No. 1528041 describes MeSO ₂ N(Ph) − as an antifungal preservative.
It has been suggested to use SCl ₂ CCl ₂ F (where Me is a metal), U.S. Pat. Formulations based on boric acid and alkylene oxide have been proposed. Furthermore, British Patent No. 1467420 proposes a solution of an organotin compound and a quaternary ammonium base. Soviet inventor certificate no.
Nos. 537814 and 571376 contain turpentine (oil).
Compositions containing CuO and rosin or CuSO ₄ , Na ₂ Cr ₂ O ₇ and H ₃ BO ₃ in acetic acid are taught. During the past few decades, efforts have continued to improve the properties of low-quality wood varieties by impregnating them with synthetic resins containing monomers and oligomers and polycondensing them by thermochemical methods. I've been exposed to it. For example, according to US Pat. No. 4,194,033, low quality wood is treated with alkylamines.
According to Japanese Patent Application No. 53-30764, an aqueous solution of formaldehyde is further used for treatment. In order to make the wood absorb free formaldehyde, boric acid is further added to the aqueous solution (patent application 1983-
No. 117611). In the USSR, impregnating compositions include phenolic alcohols (USSR Inventor's Certificate No. 404,620) and their numerous modifications, such as 30% solutions of maleic anhydride (USSR Inventor's Certificate No. 620,373), combinations of ethylene and higher fatty alcohols. condensates (USSR inventor's certificate no. 536044) and urea formaldehyde resin (USSR inventor's certificate no.
575218) with success. Patent application Nos. 1987-35401, 52-79004 and 49-
43126 and Polish Patent No. 41878, satisfactory results are obtained using low molecular weight polycondensates of phenol and formaldehyde. In order to absorb formaldehyde odors, it has been proposed to treat wood with a solution containing sodium sulfite and ammonium salts (Japanese Patent Application No. 1983-1999).
No. 43126). The disadvantages of modifying wood with phenolic alcohols or phenol/formaldehyde oligomers are that the impregnation is not homogeneous, the wood becomes corrugated or cracked, and the impregnating composition is unstable. For this reason, impregnation and subsequent curing of the impregnating composition must be carried out under pressure and with drying at a gradually increasing temperature from 30-45°C to 100-120°C. However, curing must be carried out at a temperature of 160 to 180°C (Japanese Patent Application No. 1983-20483). However, this curing temperature deteriorates the properties of the modified wood. Impregnating compositions containing a methylol derivative of carbamide, formaldehyde and a polymerization initiator are also known (West German Patent No. 2063171). Furthermore, Japanese Patent Application No. 52-24082 teaches impregnating compositions containing phenol, dihydroxybenzene and melamine or urea, with the addition of fire-retardant salts. The wood is treated in two steps.
That is, after evaporating the solvent at a temperature of 160 °C,
The wood is treated with formaldehyde at the same time as the impregnation composition is cured. On the other hand, in Japanese Patent Application No. 52-24082, cellulose derivatives are blended into the starting mixture of monomers to produce phenolic resins, urea resins, melamine resins or urea/urea resins.
It has been taught to improve the mechanical strength properties of wood modified with impregnating compositions based on melamine/formaldehyde resins. The prior art composition closest to the impregnating composition of the present invention in terms of composition and results obtained is the impregnating composition described in U.S. Pat. be. This impregnating composition is made by mixing the monomers resorcinol and dimethylol urea. Although the impregnating composition described in US Pat. No. 3,832,251 has some advantages, it also has some disadvantages as follows. (1) Free formaldehyde (up to 2%) is present in the impregnating composition, and this formaldehyde is therefore present in the modified wood in an amount determined by the equilibrium of the dimethylol urea formation and decomposition reactions. Health and safety issues remain during use and when the ski material is subsequently processed. (2) Due to the low stability of the impregnation composition, the drying temperature must be lowered.
The temperature cannot be higher than 50°C, and the dry solids content cannot be higher than 30% (the dry solids content is 50% only when producing small quantities of the impregnating composition). (3) Because the stability of the ethanol aqueous solution of dimethylol urea is low, dimethylol urea was prepared on the spot.
In other words, it must be made directly at the site of use. For this reason, the impregnating composition cannot be produced intensively. (4) Due to its brittleness, the wood modified with this impregnating composition poses a problem in mechanical strength when manufacturing ski edges and ski bases. The object of the present invention is to provide an impregnating composition for thermochemical modification of wood consisting of a monomer resorcinol and a formaldehyde donor in an alcoholic aqueous solution containing ethanol, in which the monomer resorcinol and the formaldehyde donor have a hydroxy group content of 12.0. ~13.3 meq/g of water-soluble oil sier containing crude phenol, urea, hexamethylenetetramine and molecular complexes in equilibrium between the phenol and urea and hexamethylenetetramine, and also containing ethylene glycol, its congeners or glycerin. and the composition is 100 parts by weight of water-soluble oil sier crude phenol,
28-36 parts by weight of urea, 35-40 parts by weight of formaldehyde, 13-15 parts by weight of ammonia, 3-10 parts by weight of ethylene glycol, its homologues or glycerin, 5-1750 parts by weight of ethanol, and 100-100 parts by weight of water.
An object of the present invention is to provide an impregnating composition characterized in that the amount of the impregnating composition is 3370 parts by weight. The dry solids content of the impregnating composition according to the invention is from 3 to 60
within the range of % by weight. This is one of the advantages of the impregnating composition according to the invention, which improves the physical and chemical properties of modified wood. It is undesirable to use impregnating compositions with a dry solids content of less than 3% by weight. This is because the impregnating composition loses its modifying effect. When the dry solid content exceeds 60% by weight, the viscosity increases rapidly and the modification effect does not become large. The impregnating composition (which has both high stability and dry solids content and is free of free formaldehyde)
The impregnating composition contains a molecular complex of water-soluble oil sier crude phenol, urea and hexamethylenetetramine in an alcoholic aqueous solution, according to the following equilibrium reaction equation: The overall properties of the system are mainly improved by being in the equilibrium state shown by . Note that the required reactivity under curing conditions is based on the phenol component, which is highly reactive and has a high hydroxyl group content.
Obtained using 12.0-13.3 mequiv/g of Sier water-soluble total phenols. The term "water-soluble oil sier crude phenol" as used herein means that obtained by heat treatment of Estonian oil sier. During heat treatment of combustible sier, a portion of the phenols (2-2.5% by weight based on oil sier) are recovered together with gattal water. On the other hand, the remaining part can be obtained by further washing the oil siere with water. Extraction of these waters with a phenol content of about 10 g/ml with an organic solvent yields Schier water-soluble total phenols boiling at temperatures in the range 240-360°C. These phenols contain about 10% by weight monohydric phenols and about 90% by weight dihydric phenols. The divalent phenol was found to be an alkylresorcinol. As a result of recent research, it has become possible to determine the chemical composition of water-soluble oilsier crude phenols. The chemical composition is summarized in Table 1. Table 1 Chemical composition content, weight % 1 2- monohydric phenol 8.6-10.4 Resorcinol 1.6-2.3 2-,4-methylresorcinol 2.6-3.1 5-methylresorcinol 28.0-30.3 2,4-dimethylresorcinol 0.7-0.8 4,6 -Dimethylresorcinol 1.1-1.5 2,5-dimethylresorcinol 5.8-6.4 5-ethylresorcinol 10.2-10.7 2-ethyl-5-methylresorcinol
1.7-1.8 4,5-dimethylresorcinol 5.7-7.5 5-ethenylresorcinol 1.3-1.7 2-methyl-5-ethylresorcinol
1.9-2.0 2,4,5-trimethylresorcinol
2.1~3.0 5-bropylresorcinol 1.9~2.7 4-methyl-5-ethylresorcinol
1.1 to 1.5 Other alkyl resorcinols 18.4 to 22.6 However, four types of basic components including Ingredients are 5-methylresorcinol, 5-ethylresorcinol, 2,5
-dimethylresorcinol and 4,5-dimethylresorcinol, the total amount of which is within a narrow range (50
-55% by weight), of which 28-30% by weight is 5-methylresorcinol. A major feature of water-soluble oil sier crude phenol is that it has higher reactivity than resorcinol. This can be explained by the presence of 5-substituted alkyl resorcinols in the composition of the oil sier crude phenol. The reason for increasing the final temperature of the material from impregnated wood is that it increases the stability of the impregnating composition according to the invention. The dry solids content of the impregnation composition increases to 60% by weight because the mixture of molecular complexes formulated in the equilibrium solution is dissolved in a solvent, i.e., an alcohol-based aqueous solution (a mixture of ethanol and ethylene glycol, their congeners, or glycerin in water). This is because homogeneity is maintained even in small amounts. The improvement in elasticity of modified wood is due to the condensation reaction between hexamethylenetetramine and water-soluble oil sier crude phenol and urea that occurs under drying and compression conditions of the impregnated wood, resulting in the generation of ammonia, which is converted into high-boiling alcohol. (Together with ethylene glycol, its congeners or glycerin, it imparts a plasticizing effect to the wood.) Improvements in the health and safety aspects of the working environment during wood modification are due to the fact that the impregnating composition according to the invention does not contain free formaldehyde. The dry solids content of the impregnating composition is increased and the final drying temperature of the material from the impregnated wood can also be increased, making it possible to increase the production rate of the modification and wood drying process. Also, the hydroxy group content is 12.0~
13.3meq/g water-soluble oil Sierre 100 parts by weight of crude phenol, 28-36 parts by weight of urea, 3-10 parts by weight of polyhydric phenol (ethylene glycol, its congeners or glycerin), 6-1025 parts by weight of ethanol and 3 parts by weight of water. ~60~ of a mixture consisting of ~1492 parts by weight
Heating at a temperature within the range of 95°C to obtain an alcoholic aqueous solution containing the above-mentioned water-soluble oilsier crude phenol, urea and molecular complexes of these phenols and urea, and separately a 37% aqueous solution of formaldehyde 95-107% by weight part, 27% of ammonia
Mix 54 to 62 parts by weight of an aqueous solution, 1 to 725 parts by weight of ethanol, and 1 to 1,764 parts by weight of water, and add 20 parts of this mixture by weight.
Make an alcoholic aqueous solution of hexamethylenetetramine by maintaining the temperature within the range of ~60 °C;
The alcohol-based aqueous solution containing the water-soluble oil sier crude phenol, urea, and a molecular complex of these phenols and urea is mixed with the alcohol-based aqueous solution of hexamethylenetetramine in a weight ratio of 1:1. It also relates to a method for producing an impregnating composition for thermochemical modification. As a result of mixing the above two alcoholic aqueous solutions, a water-soluble oil siel containing crude phenol, urea, hexamethylenetetramine, and a molecular complex of the phenol, urea, and hexamethylenetetramine with a hydroxy group content of 12.0 to 13.3 meq/g is obtained. An impregnating composition consisting of an aqueous alcoholic solution in equilibrium is produced. When preparing an alcoholic aqueous solution containing crude phenol, urea, and a molecular complex of these phenols and urea (hereinafter referred to as solution A), ensure that each component (phenol and urea) is dissolved together in the solvent. Temperature to 60-95
Must be maintained within ℃ range. When preparing an aqueous ethanol solution of hexamethylenetetramine (hereinafter referred to as solution B), it is necessary to prevent the temperature from exceeding 60°C since the starting components (formaldehyde and ammonia) are volatile. To simplify the preparation of the impregnating composition, solution A
The mixing weight ratio of and B is selected to be 1:1. However, compositions with other proportions can also be produced, but this would complicate the process. There is no limit to the storage period of the alcoholic aqueous solutions A and B, and their production can also be carried out intensively.
Therefore, the synthesis of dimethylol urea (formaldehyde donor), which was not limited in the woodworking field, can be performed in a limited manner, and the impregnating composition can be produced intensively. Impregnating compositions for thermochemical modification of wood are produced by a three-step mechanical and chemical process. (1) Prepare alcoholic aqueous solution A in a reactor equipped with a stirrer, thermometer, cooler, and cooling/heating jacket. Hydroxy group content is 12.0~
13.3 meq/g of water-soluble oil-sier crude phenol was introduced into the reactor, heated to a temperature of 40°C, urea was added, the temperature was increased to 60-95°C, and the mixture of water-soluble oil-sier crude phenol and urea was added. Stir until a molecular complex forms and add polyhydric alcohol [ethylene glycol, its homologs (diethylene glycol, triethylene glycol) or glycerin], water and ethanol. The solution is stirred and cooled before being removed from the reactor. It has an unlimited shelf life and can be produced intensively. (2) Alcohol-based aqueous solution B is produced in a similar reactor, but this reactor contains 37% of formaldehyde.
% aqueous solution. With continuous stirring and cooling, a 24% aqueous solution of ammonia is added in such a proportion that the temperature of the mixture does not exceed 60°C. Cool the solution and remove from the reactor. It has an unlimited shelf life and can be produced intensively. (3) Mix the obtained alcoholic aqueous solutions A and B in a 1:1 ratio at a temperature within the range of 20 to 30°C for 15 to 30 minutes until the molecular complex reaches an equilibrium state in the impregnating solution.
Mix in a weight ratio of The storage period of the resulting impregnated composition is 20 at 20-25 ° C.
For days, this composition is free of free formaldehyde. The method of manufacturing impregnating compositions according to the invention is further illustrated in Examples 1-5 of Table 2. Table 3 shows various embodiments of the impregnating compositions of the present invention prepared according to Examples 1-5 of Table 2. Table 4 compares the properties of the impregnating composition according to the present invention and the conventional impregnating composition described in US Pat. No. 3,832,251.

【table】

【table】

【expressed.
Ingredients can be manufactured centrally.
Thermochemical modification of wood with the impregnating composition of the present invention involves impregnating the wood under pressure with preliminary evacuation in an open bath or autoclave, and then impregnating the wood for 20 to 20 minutes.
It consists of drying at a temperature of 90° C., thereby preliminarily polycondensing the composition used. Further, the polycondensation is carried out at a temperature of 100-180°C, preferably 100-120°C, under a pressure of 0.2-6.0 MPa. Table 5 shows a comparison of the physical and mechanical properties of modified wood obtained using the impregnation composition of the present invention and modified wood obtained using the known composition described in U.S. Pat. No. 3,832,251. . As can be seen from Table 5, when the dry solids content of the impregnating compositions is equal, the physical and mechanical properties of wood modified using the impregnating composition according to the invention are better than those according to U.S. Pat. It is 1.1-1.7 times better than that of wood modified with impregnating compositions.

【table】

Claims (1)

[Scope of Claims] 1. An impregnating composition for thermochemical modification of wood comprising a monomer resorcinol and a donor of formaldehyde in an alcoholic aqueous solution containing ethanol, wherein the monomer resorcinol and the donor of formaldehyde have a hydroxyl content. is 12.0~
Contains 13.3meq/g of water-soluble oil sier crude phenol, urea, hexamethylenetetramine and a molecular complex in equilibrium between the phenol and urea and hexamethylenetetramine, and also contains ethylene glycol, its congeners or glycerin. , and the composition is 100 parts by weight of water-soluble oil sier crude phenol, 28-36 parts by weight of urea, 35-40 parts by weight of formaldehyde, 13-15 parts by weight of ammonia, 3-10 parts by weight of ethylene glycol, its homolog or glycerin, An impregnating composition comprising 5 to 1,750 parts by weight of ethanol and 100 to 3,370 parts by weight of water. 2 100 parts by weight of water-soluble oil sier crude phenol with a hydroxy group content of 12.0 to 13.3 meq/g,
28-36 parts by weight of urea, 3-10 parts of polyhydric alcohol (ethylene glycol, its congeners or glycerin)
parts by weight, 6 to 1025 parts by weight of ethanol and 3 to 10 parts by weight of water
A mixture consisting of 1492 parts by weight is heated at a temperature within the range of 60 to 95°C to obtain an alcoholic aqueous solution containing the above-mentioned water-soluble oilsier crude phenol, urea, and molecular complexes of these phenols and urea, and separately. 37% aqueous solution of formaldehyde 95
~107 parts by weight, 54-62 parts by weight of a 27% aqueous solution of ammonia, 1-725 parts by weight of ethanol and 1-1764 parts by weight of water.
Parts by weight are mixed and this mixture is maintained at a temperature within the range of 20-60°C to form an alcoholic aqueous solution of hexamethylenetetramine, and the above-mentioned oil sier crude phenol, urea and the molecular complex of the phenol and urea are prepared. The impregnating composition for thermochemical modification of wood according to claim 1, characterized in that an alcoholic aqueous solution containing hexamethylenetetramine is mixed with the alcoholic aqueous solution of hexamethylenetetramine in a weight ratio of 1:1. manufacturing method.