JP3343564B2 - Method for producing resin raw material composition from wood-based material using cyclic carbonates - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a resin raw material composition by liquefying a wood-based substance which is a renewable resource.

[0002]

2. Description of the Related Art At present, in the wood industry and the like, treatment of waste such as bark, sawdust, and board waste discharged at the time of sawing has become a major problem. In the forestry industry, there is an urgent need to use so-called thinned wood effectively. Furthermore, in urban areas, disposal of construction waste is a major problem. Therefore, development of effective utilization methods of these woody wastes is urgent. As one of them, an attempt has been made to obtain a liquid-modified substance in which a wood-based substance is treated with an acid in an organic solvent, partially reacted with the solvent and dissolved therein. This is called liquefaction of wood-based materials.

[0003] Liquefaction of wood-based materials was started in 1925 by Fie.
It is thought that rz-David et al. began to treat cellulose under high-pressure hydrogen to obtain a liquid. Since then, attempts have been made to liquefy wood materials using various catalysts under high temperature and high pressure. After that, the liquefaction method showed various progress. In 1986, Hoechst treated wood flour in the presence of phenol using a sulfuric acid catalyst, added magnesium oxide, neutralized it, removed unreacted phenol, and set hardening reactivity. A patent for obtaining a resin has been filed (Japanese Patent Publication No. 61-269)
No. 7). Shiraishi et al. Have obtained a liquefied product by treating a woody material with phenols at a high temperature (250 ° C.) without a catalyst (JP-A-61-261358). Regarding liquefaction using phenols, as an improvement of the above technology,
For example, JP-A-2-212498, JP-A-3-59
No. 035 and Japanese Patent No. 2611166 are known.

On the other hand, it has been found that liquefaction is possible even when alcohols, especially polyhydric alcohols, are used instead of phenols. JP-A-62-79230 discloses a method of liquefying a woody material with an alcohol or ketone at 250 ° C. in a pressure vessel. JP 6
No. 4-36653 discloses that a wood solution is prepared by reacting a wood material in a pressure-resistant reaction tube at 250 ° C. for 2.5 hours in the presence of dibasic acid anhydride, polyhydric alcohols and acetone as a solvent. And a reaction at 180 ° C. using a potassium hydroxide catalyst in a pressure-resistant reaction vessel to remove unreacted ε-caprolactone and react with a polyvalent isocyanate compound to obtain a foam. ing. JP-A-4-106128 discloses that liquefaction is possible by using polyethylene glycols under normal pressure under a sulfuric acid catalyst, and that the liquefaction reaction proceeds better in a system to which glycerin is added. Have been. Here, even in a mixed solvent system of polyethylene glycol 400 and glycerin in which liquefaction proceeds fastest, it takes more than one hour at a reaction temperature of 150 ° C. to liquefy to a residue ratio of 10% or less. JP-A-8-225653 discloses that wood flour can be liquefied under a sulfuric acid catalyst in a mixed solution of polyhydric alcohol and ε-caprolactone which is polymerized by a ring opening reaction as a polyester polyol raw material. Here, liquefaction of ε-caprolactone alone was not performed.

[0005] As can be seen from the above-mentioned documents, a method for liquefying a wood-based substance is a method in which a phenol or a polyhydric alcohol is used in a pressure-resistant reaction vessel without a catalyst, or
It is classified into a method of using an acid catalyst under normal pressure. If a reaction vessel having a highly acid-resistant inner wall is used, liquefaction at normal pressure is easy in handling. The liquefied solvents such as phenols and alcohols used in the above method have been attracting attention as delignification solvents for leaving cellulose in solvolysis pulping, which is one field of pulping. It is known that most of lignin is first liquefied in liquefaction using these as a liquefaction solvent, irrespective of softwood or hardwood. However, there is no report on liquefaction that leaves lignins, which are polyphenols, in conifers.

[0006] In the above method, the reaction temperature is set at 15 to make the liquefaction proceed to a residue ratio of 10% or less.
About 0 ° C. was required, and the liquefaction time required at least one hour. As described above, the conventional technique is a method of liquefying a woody material using phenols or alcohols, which has been studied for solvolysis pulping, and there is no example of using cyclic carbonic acid as a reaction solvent.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to use a cyclic carbonic acid which is not conventionally known as a liquefying solvent for wood-based materials, to thereby liquefy the wood-based materials at a low temperature and in a short time to obtain a resin raw material. In producing a composition.

That is, according to the present invention, the woody substance is decomposed by the acid by mixing the cyclic carbonic acid, the woody substance and the acid, and heating the mixture under normal pressure in a temperature range from the melting point to the boiling point of the cyclic carbonic acid. the product of this decomposition is to provide a manufacturing method of the resin raw material composition from wood-based material characterized that you liquefaction is reacted with a cyclic carbonate such as to.

[0009] The present invention also includes 1) a cyclic carbonate compound and 2) a mixture and 3 the least one compound selected from alcohols and phenols) wood-based material and a 4) were mixed and acids, 1) By heating in a temperature range from the melting point to the boiling point of the cyclic carbonic acid, 3) the wood-based substance is decomposed by 4) acids, and the resulting product is selected from 1) cyclic carbonic acid and 2) alcohols and phenols. The present invention provides a method for producing a resin raw material composition from a wood-based substance, characterized by reacting with a mixture obtained by mixing at least one compound.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION As a starting material of the resin raw material composition of the present invention, various woody materials such as sawdust, wood flour, wood chips, veneer chips, plywood cuttings, bark, etc. A substance is used, and a powdery wood-based substance is preferably used.

The cyclic carbonates used in the present invention include:
Examples include ethylene carbonate and propylene carbonate. The above cyclic carbonates can be used alone or as a mixture.

The mixing ratio of the woody substance and the cyclic carbonate is not particularly limited as long as both can be uniformly mixed.
The wood-based substance is preferably mixed in an amount of 1 to 2,000 parts by weight, more preferably 10 to 700 parts by weight, based on 100 parts by weight of the cyclic carbonate. When a mixture of a cyclic carbonic acid and at least one compound selected from alcohols and phenols is used, a wood-based substance is preferably used in an amount of 1 to 2,000 parts by weight, more preferably 100 parts by weight of the mixture. 10 to 700 parts by weight are mixed.

In the present invention, when the woody substance is obtained from a broad-leaved tree such as birch, the woody substance can be almost liquefied by the cyclic carbonic acid. When the woody substance is obtained from conifers such as cedar, lignins can be left and other celluloses can be liquefied. Then, the remaining lignins can be filtered and used for other purposes. Normal liquefaction (residue rate 10%
When the following is desired, lignins are liquefied by using a mixture of cyclic carbonates and alcohols or phenols instead of cyclic carbonates.

The alcohols to be mixed with the cyclic carbonates include aliphatic and aromatic monohydric alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol and benzyl alcohol, and fatty acids such as ethylene glycol, propylene glycol and polyethylene glycol. Aliphatic and aromatic dihydric alcohols, aliphatic and aromatic trihydric alcohols such as glycerin, and aliphatic and aromatic tetrahydric alcohols such as pentaerythritol are used. As phenols, phenol, o-, m-,
p-cresol, 3,5-, 2,3-, 2,6-xylenol, o-, m-, p-propylphenol, o-,
m-, p-butylphenol, o-, m-, p-secondary butylphenol, o-, m-, p-tert-butylphenol, hexylphenol, phenylphenol, octylphenol, monohydric phenols such as naphthol, catechol, resorcinol, Quinol,
Bivalent phenols such as bisphenol A, bisphenol B and bisphenol F, trivalent phenols such as pyrogallol, phloroglucyl, trihydrobenzene, and gallic acid, and chlorides thereof are used. The proportion of the alcohol or phenol used is preferably 0.1 to 10% by weight based on 100 parts by weight of the cyclic carbonate.

The acids used in the present invention include hydrochloric acid,
Mineral acids such as sulfuric acid and nitric acid, Bronsted acids such as organic acids such as formic acid, acetic acid and p-toluenesulfonic acid and Lewis acids such as boron trifluoride, aluminum chloride and stannic chloride or ethers thereof. , Alcohols, phenol complexes and the like. It is preferable to use these in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the cyclic carbonate.

Further, in order to alleviate the runaway reaction due to heat generation in the initial stage of the reaction or to remove a large amount of water from the woody material as a starting material to the outside of the system, an azeotropic solvent having an azeotropic property with water or a resin formed. It is preferable to add a solvent or the like that dissolves the raw material composition at the beginning of the reaction or during the reaction. Examples of the azeotropic solvent include toluene.

The reactor used in the present invention does not need to be a pressure-resistant reactor, but may be an acid-resistant normal-pressure reactor. It is particularly desirable to have a stirrer to which a large torque can be applied in order to make the reaction uniform. The liquefaction reaction is preferably performed at 120 to 150 ° C. with stirring for 10 minutes to 3 hours.

The wood-based substance is liquefied by heating and stirring with the cyclic carbonic acid and the like in this way, to obtain a resin raw material composition. The resin raw material composition obtained according to the present invention has reactivity with alcohols, epoxies, isocyanates, and the like, and a reaction product thereof has a property of being a polymer resin substance by a catalyst or heating. It is used as a raw material for adhesives, molded products and the like.

[0019]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples of the present invention and Comparative Examples thereof, but the present invention is not limited to these Examples.

Example 1 1.5 g of concentrated sulfuric acid and 50 g of ethylene carbonate were placed in a 100 ml three-necked flask equipped with a thermometer, a cooling tube and a stirrer.
Weigh and mix with stirring. 10 g of dried birch sawdust is added to the mixture, and the mixture is further stirred. After confirming that birch sawdust was well mixed with ethylene carbonate, the temperature in the system was increased to 150 ° C with stirring, and the reaction was carried out at the same temperature for 15 minutes. I got This product was quantitatively transferred to a G3 glass filter, washed and filtered with a dioxane / water (8/2 vol) mixed solution, and as a result, some undissolved matter was obtained on the filter. The filter containing the undissolved substance is placed in a dryer at 110 ± 5 ° C., 2
Dry weight of undissolved material obtained after drying for 4 hours is 0.37 g
(Residue rate: 3.7%). In the subsequent liquefaction,
Substances that do not dissolve in the dioxane / water (8/2 vol) mixture in the liquefied product are defined as residues in the liquefaction. The dry weight percentage of the residue relative to the dry weight of the wood material used is defined as the residue ratio.

The highly viscous product obtained by evaporating the dioxane / water mixture from the filtrate is a substance which is completely dissolved in dimethylformamide, phenol, tetrahydrofuran, dimethylsulfoxide and the like, and is a substance which is almost dissolved in methyl alcohol, acetone and the like. there were.

Example 2 In Example 1, propylene carbonate was used in place of ethylene carbonate, and liquefaction (reaction after raising the system temperature to 150 ° C.) was performed for 40 minutes in the same manner. %
A degree of liquefaction product was obtained. The soluble part of this product was soluble in the same solvent as in Example 1.

Example 3 The reaction temperature in Example 1 was changed from 150 ° C. to 120 ° C.
The reaction time was changed to 3 hours, and liquefaction was performed in the same manner. As a result, a liquefied product having a residue ratio of about 3% was obtained. The soluble part of this product was soluble in the same solvent as in Example 1.

Example 4 Liquefaction was carried out in the same manner as in Example 1 except that cedar wood flour was used instead of birch sawdust.
A 9.4% liquefaction was obtained. The infrared spectrum of the cedar residue almost coincides with that of lignin, and the amount of the residue is close to the measured Klason lignin value of 31.5 of the used cedar wood flour. It is determined to be insolubilized due to the above.

When the same liquefaction was carried out in this example using cypress wood flour instead of cedar wood flour, a liquefied product containing 21.4% residue was obtained. The amount of this residue was also close to the measured amount of Klason lignin in Hinoki wood flour, 25.7%, and its infrared spectrum was almost identical to that of softwood lignin.

From the above, it can be seen that in softwood, ethylene carbonate causes little liquefaction of lignin and mainly liquefies cellulose.

Example 5 The same liquefaction was performed as in Example 4 except that ethylene carbonate / ethylene glycol mixture (8/2 weight ratio) was used instead of ethylene carbonate.
% Liquefied product was obtained. The soluble part of this product was soluble in the solvent of Example 1.

This indicates that lignin was liquefied by mixing ethylene glycol.

Example 6 In Example 5, an ethylene carbonate / phenol mixed solution (8 /
When the reaction temperature was lowered to 140 ° C. and the same liquefaction was performed, the reaction time was 25 minutes and the residue ratio was 1%.
A degree of liquefaction product was obtained. The soluble part of this product was soluble in the solvent of Example 1.

Example 7 1.5 g of concentrated sulfuric acid and 50 g of ethylene carbonate are weighed and mixed in a 100 ml three-necked flask equipped with a thermometer, a cooling tube equipped with a Dean-Stark moisture trap and a stirring device. To this mixture was added 11.5 g of birch sawdust having a water content of 13% by weight, and then 10 g of toluene.
And further stirred. After confirming that the birch sawdust was well mixed with the mixture of ethylene carbonate and toluene, the temperature in the system was increased to 85 ° C. with stirring and maintained for a while, and water was removed from the system by azeotropic distillation with toluene. After confirming that the temperature of the system started to rise, the temperature was raised to 150 ° C. while removing the plug of the water trap and removing toluene, and the reaction was carried out for 20 minutes. Then, the reaction vessel was cooled to obtain a black highly viscous product. This product was quantitatively transferred to a G3 glass filter, and dioxane / water (8 /
2vol) As a result of washing and filtering with the mixed solution, some undissolved substances were obtained on the filter. The dry weight of the undissolved material obtained by drying the filter containing the undissolved material in a dryer at 110 ± 5 ° C. for 24 hours was 0.15 g (residue ratio: 1.5%). The highly viscous product obtained by evaporating the dioxane / water mixture from the filtrate is a substance which is completely soluble in dimethylformamide, phenol, tetrahydrofuran, dimethylsulfoxide and the like as shown in Example 1, and is substantially soluble in methyl alcohol, acetone and the like. Met.

[0031]

According to the present invention, by using a novel liquefied solvent, a resin raw material composition which becomes various resin raw materials from a wood-based material can have a shorter reaction time than the conventional reaction time in alcohol liquefaction, and It is possible to liquefy at a reaction temperature lower than the conventional liquefaction temperature.

When a woody substance obtained from coniferous wood is used as a raw material and cyclic carbonates are used, only celluloses can be liquefied, and the remaining lignins can be filtered and used for other purposes. When a mixture of cyclic carbonates and alcohols or phenols is used, ordinary liquefaction (residue rate of 10% or less) can be achieved.

Further, when the woody substance as a raw material contains a large amount of water, it can be easily discharged out of the system during the reaction.

Continuation of the front page (56) References JP-A-51-110002 (JP, A) JP-A-7-32309 (JP, A) JP-A-61-261358 (JP, A) JP-A-2-212498 (JP) JP-A-8-225653 (JP, A) JP-A-62-279230 (JP, A) JP-A-2000-273310 (JP, A) JP-A-10-182812 (JP, A) JP-A-238255 (JP, A) JP-A-50-10866 (JP, A) JP-A-63-153102 (JP, A) JP-B-61-2697 (JP, B2) US Patent 4,359,507 (US, A) International publication 96/9902 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08H 5/00-5/04 C08L 97/00-97/02 C09J 197/00-197/02 CA ( STN) REGISTRY (STN)

Claims (5)

(57) [Claims] 1. A method in which a cyclic carbonic acid, a woody substance, and an acid are mixed, and the mixture is heated under normal pressure in a temperature range from the melting point to the boiling point of the cyclic carbonic acid, whereby the woody substance is decomposed by the acid and the decomposition is performed. preparation of the resin raw material composition from wood-based material characterized that you liquefaction is reacted with a cyclic carbonate such product by. 2. A mixture of 1) a cyclic carbonate and 2) a mixture of at least one compound selected from alcohols and phenols, 3) a woody substance and 4) an acid, 1) a cyclic carbonate 3) The woody substance is decomposed by acids 4) and the product of this decomposition is at least selected from 1) cyclic carbonates and 2) alcohols and phenols. preparation of the resin raw material composition from wood-based material characterized that you liquefaction reacted with a mixture obtained by mixing one compound. 3. The method according to claim 1, wherein the cyclic carbonic acid is ethylene carbonate or propylene carbonate. 4. The method for producing a resin raw material composition from woody substances according to claim 2, wherein the alcohol is ethylene glycol. 5. In order to remove water from the wood-based substance, a step of heating and evaporating the water of the wood-based substance under reduced pressure or normal pressure to remove the water out of the system, or adding an azeotropic solvent which azeotropes with water, The method for producing a resin raw material composition from a woody substance according to any one of claims 1 to 4, further comprising a step of removing the resin from the system.