JP5348113B2 - Method for producing lignin resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lignin resin composition excellent in curing property and to provide a molding material using the lignin resin composition. <P>SOLUTION: The lignin resin composition indispensably consists of a lignin compound and a crosslinking agent, wherein the lignin compound has a phenolic hydroxy group and an alcoholic hydroxy group of the molar ratio in the range of 9/1 to 8/2, provided by degrading biomass. Therein, one kind or two kinds selected from lignin derivatives produced by introducing a reactive group into the lignin compound are preferably used. The reactive group in the lignin derivatives has an epoxy group. The molding material including the lignin resin composition and a filler is also provided. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a method for producing a lignin resin composition.

In recent years, the development of technology using biomass has attracted attention for the purpose of developing alternative petroleum resources. As a kind of biomass, lignin existing in trees is known. As applications of lignin, water reducing agents for fuel and cement are mainly known. In addition, taking advantage of a structure containing a large amount of phenolic structure of lignin, the use of lignin as a resin material such as a phenol resin or an epoxy resin has been studied for a long time (see, for example, Patent Document 1). When a functional group for crosslinking such as an epoxy group is introduced into lignin as the resin raw material, an alcoholic hydroxyl group having low reactivity in lignin inhibits the introduction of the functional group. According to the report by Tsujioka et al., The molar ratio of the phenolic hydroxyl group to the alcoholic hydroxyl group is about 0.8: 1.0 to 1.5: 1.0 (see, for example, Non-Patent Document 1).
In addition, when a functional group for crosslinking such as an epoxy group is introduced into lignin, the alcoholic OH group is inferior in reactivity, so that it is necessary to introduce a phenol compound beforehand. Hasegawa et al. Are investigating epoxidation of lignophenol, but despite the increase in phenolic OH groups, there is a problem that the introduction rate of epoxy groups is reduced to around 20% (for example, non-patented). Reference 2). Therefore, these lignophenols and epoxidized products thereof have a problem that they are inferior in curability and heat resistance when applied to molding materials.

JP 2004-238539 A

K. Mikame, M.M. Funaoka, Polym. J. et al. , 38, 585-591, 2006J . Kadota, K .; Hasegawa, M.M. Funoka Journal of Network Polymer. Japan, 27, 118-125, 2006

As described above, the lignophenol derivative also has a problem that the introduction rate of the reactive group is low, and the introduction rate of the reactive group to the lignin decomposition product and the improvement of the curability of the lignin resin are required.
This invention is made | formed in view of this condition, and provides the method of manufacturing a lignin resin composition excellent in sclerosis | hardenability reliably.

  As a result of intensive studies to achieve the above problems, the present inventors have achieved excellent curability by using a lignin compound having a specific proportion of a phenolic hydroxyl group or other reactive group and a crosslinking agent. As a result, it was found that a resin composition capable of realizing physical properties was obtained, and a method for reliably producing such a resin composition was found, and the present invention was completed.

Such an object is achieved by the present inventions (1) to (3) below.
(1) A method for producing a lignin resin composition comprising, as essential components, a lignin derivative formed by introducing an epoxy group into a phenolic hydroxyl group of a lignin compound obtained by decomposing biomass and a crosslinking agent,
A decomposition step of placing biomass in the presence of water and decomposing them under high temperature and high pressure;
An immersion step of immersing the insoluble matter in the processed product obtained by the decomposition step in a solvent in which lignin is soluble;
A distillation step for distilling off the solvent in which the lignin is soluble from the soluble matter in the treated product obtained by the immersion step;
A reactive group introduction step of mixing the treated product obtained by the distillation step and the compound containing the epoxy group ;
A cross-linking agent mixing step of mixing the processed product obtained by the reactive group introducing step and the cross-linking agent,
The said lignin compound is a manufacturing method of the lignin resin composition characterized by including phenolic hydroxyl group and alcoholic hydroxyl group by the ratio of 9: 1 to 8: 2 by molar ratio.
(2) the decomposition step, the biomass in the presence of water, treatment temperature 150 to 400 ° C., process pressure 1.0～40MPa, according to the above (1) is intended to decomposition treatment by the following treatment time 480 min A method for producing a lignin resin composition.
(3) The lignin resin composition according to the above (1) or (2) , wherein the lignin resin composition has a lignin compound content of 40 to 95 wt% and a crosslinking agent content of 5 to 60 wt%. Method.

  According to this invention, the lignin resin composition excellent in sclerosis | hardenability can be manufactured reliably. Moreover, the molding material using the lignin resin composition obtained by this invention is excellent in sclerosis | hardenability.

The present invention is a method for producing a resin composition comprising a lignin compound and a cross-linking agent as essential components, and is obtained by decomposing biomass with a phenolic hydroxyl group and an alcoholic hydroxyl group in a molar ratio of 9: 1 to 1. One or two selected from lignin compounds having a ratio of 8: 2 (hereinafter sometimes referred to as lignin degradation products) and lignin derivatives in which reactive groups are introduced into the phenolic hydroxyl groups of the lignin compounds are used. It is characterized by this. According to such this invention, the lignin resin composition excellent in sclerosis | hardenability can be manufactured reliably, and the molding material using this lignin resin composition can be provided.
Examples of the structure having a phenolic hydroxyl group in the lignin compound include a phenol structure, a guaiacol structure, and a 2,6-dimethoxyphenol structure.

  The lignin degradation product in the lignin compound used in the present invention is obtained by decomposing biomass, and has a phenolic hydroxyl group and an alcoholic hydroxyl group in a molar ratio of 9: 1 to 8: 2. Further, the lignin derivative having a reactive group other than the phenolic hydroxyl group in the lignin compound includes a reactive group such as an epoxy group, a vinyl group, an ethynyl group, a maleimide group, a cyanate group and an isocyanate group, which will be described later. Was introduced. Since the lignin compound including the lignin derivative has a number of cross-linked sites, it has excellent properties such as curability and heat resistance when used as a molding material. Among the above, the lignin compound used in the present invention is preferably a lignin degradation product in terms of reactivity and ease of handling.

  Examples of the biomass include plants containing lignin and processed products of the plants. Examples of the plant include broad-leaved trees such as beech, birch and oak, conifers such as cedar, pine, and oak, and gramineous plants such as bamboo and rice straw. Examples of the shape of biomass used in the present invention include blocks, chips, and powders.

The lignin degradation product in the lignin compound used in the present invention can be obtained by decomposing the biomass by high-temperature and high-pressure treatment in the presence of a solvent.
As a specific example of a method for producing a lignin compound, first, the biomass is adjusted to a certain size, and then, together with a solvent, optionally a catalyst, put in a pressure vessel with a stirrer and a heating device, The biomass is decomposed while being heated and pressurized (decomposition step). Next, the content of the pressure vessel is filtered to remove the filtrate, and the water-insoluble matter is washed with water and separated. Next, the water-insoluble matter is immersed in a solvent in which the lignin compound is soluble (for example, acetone) (immersion step), the lignin compound is extracted into acetone, and the acetone is distilled off (distillation step). Thus, a lignin compound can be obtained as a lignin degradation product.

  As a magnitude | size of the biomass in the said decomposition | disassembly process, about 100 micrometers-1 cm are preferable, and 200 micrometers-500 micrometers are more preferable. At this time, the shape of the biomass may be any of a block shape, a chip shape, a powder shape and the like as described above.

  Examples of the solvent in the decomposition treatment include water, alcohols such as methanol and ethanol, phenols such as phenol and cresol, ketones, ethers, and the like, and it is particularly preferable to use water. The amount of the solvent used is preferably as large as possible with respect to the biomass, but is preferably about 2 to 10 times the biomass weight, more preferably about 3 to 5 times the biomass weight. An inorganic base such as sodium carbonate may be added as a catalyst.

  As conditions for processing the biomass at high temperature and high pressure, the processing temperature is usually preferably from 150 ° C to 400 ° C, more preferably from 200 ° C to 380 ° C. The treatment temperature can be used outside the above range, but the molecular weight of the lignin compound can be controlled by the treatment temperature, and tends to be a low molecular weight body when treated at a high temperature and a high molecular weight body when treated at a low temperature.

  The treatment time is usually preferably 0 minute to 480 minutes, and more preferably 30 minutes to 120 minutes. Although the treatment time can be used outside the above range, the phenolic hydroxyl group equivalent of the lignin compound can be controlled by the treatment time, the phenolic hydroxyl group equivalent tends to increase with short-time treatment, and tends to decrease with long-time treatment. . The pressure is preferably 1.0 MPa to 40 MPa, more preferably 1.5 MPa to 25 MPa. The pressure can be used even outside the above range, but by treating at a higher pressure, an effect equivalent to that obtained when the treatment is performed for a long time can be obtained.

By treating the biomass under the conditions within the above range, the number average molecular weight is in the preferred range of about 300 to 2,000, and furthermore, it is a preferred phenolic hydroxyl group equivalent of 100 to 200 as the lignin compound in the present invention. It becomes easy to control to the phenolic hydroxyl group equivalent of a grade.
In the specific example of the production method, the phenolic hydroxyl group equivalent and the molecular weight can be controlled independently. For example, the phenolic hydroxyl group equivalent (mainly phenolic hydroxyl group) is obtained by short-time treatment regardless of the treatment temperature. A large product of about 200 is obtained, and a small phenolic hydroxyl group equivalent is obtained by saturation at about 100 by long-time treatment.

The lignin degradation product obtained by the production method exemplified above has a phenolic hydroxyl group and an alcoholic hydroxyl group in a molar ratio of 9: 1 to 8: 2.
The lignin degradation product preferably has a polystyrene-equivalent number average molecular weight of 300 to 2,000 as measured by gel permeation chromatography. Although it can be used outside the above range, if it is less than 300, monofunctional monomers and oligomers exist as lignin degradation products, and when cured, the crosslink density may be reduced and curability may be poor. If it is larger than 2,000, the softening point of the lignin decomposition product becomes too high, which may cause the problem of difficulty in molding. The same applies to the number average molecular weight of lignin derivatives.

  Moreover, the lignin derivative in the lignin compound used in the present invention is obtained by introducing a reactive group other than a phenolic hydroxyl group into the lignin decomposition product, has a useful reactivity as a resin raw material, and obtains a high crosslinking density. Can do.

  The reactive group of the lignin derivative is a reactive group, the reactive group is self-reactive, and two or more identical reactive groups can react with each other, or other functional group As long as they can react with each other, and examples thereof include carbon-carbon unsaturated bond groups such as epoxy groups, vinyl groups, and ethynyl groups, maleimide groups, cyanate groups, and isocyanate groups. It is not limited to. Among these, an epoxy group is preferable because the cured product has high dimensional stability, water resistance, chemical resistance, and electrical insulation.

  As a method for producing the lignin derivative, a person skilled in the art can generally use a known method in which a reactive group is bonded to a phenolic hydroxyl group via a covalent bond. Can be selected. As a specific example, it can be obtained by introducing the reactive group into the phenolic hydroxyl group of the lignin degradation product obtained above.

Although the specific example of the introduction method (reactive group introduction | transduction process) of a reactive group is shown below, it is not limited to these.
When an epoxy group is introduced as a reactive group, for example, the lignin decomposition product obtained above is obtained by dissolving in epichlorohydrin and reacting with a base catalyst such as sodium hydroxide under reflux under reduced pressure. .

  When a vinyl group is introduced as a reactive group, for example, a halogen compound containing a vinyl group such as allyl halide and vinylbenzyl halide and the lignin decomposition product obtained above are dissolved in a solvent and heated. It can be obtained by reacting using a base catalyst such as sodium hydroxide.

In the present invention, the lignin degradation product obtained above is mixed with a crosslinking agent (crosslinking agent mixing step).
The crosslinking agent used in the present invention is not particularly limited as long as it has a functional group that reacts with the reactive group of the lignin compound (lignin derivative) having a phenolic hydroxyl group or a reactive group of the lignin compound. .

  As a crosslinking agent in the case of using a lignin decomposition product as a lignin compound, for phenolic hydroxyl groups contained in the lignin compound, epoxy resins such as orthocresol novolac epoxy resin and bisphenol A type epoxy resin, hexamethylene diisocyanate and toluene diisocyanate Such as urethane resins, aldehydes such as formaldehyde, acetaldehyde and paraformaldehyde, aldehyde sources such as polyoxymethylene, hexamethylenetetramine, and ordinary phenol resins such as resol-type phenolic resins. Examples thereof include compounds capable of crosslinking by electrophilic substitution reaction on the aromatic ring of the decomposition product. Hexamethylenetetramine is preferred because of its reactivity and availability.

Moreover, as a crosslinking agent in the case of using the lignin compound (lignin derivative) which has a reactive group, what is necessary is just a crosslinking agent which reacts with this reactive group, or has a self-crosslinking reactive group.
As a crosslinking agent in the case of using a lignin compound having an epoxy group as a lignin derivative, a general curing agent for an epoxy resin may be used. For example, a phenol resin such as a novolac-type phenol resin; a lignin having a phenolic hydroxyl group Compounds; amine compounds such as diethylenetriamine, m-xylylenediamine and N-aminoethylpiperazine; acid anhydrides such as phthalic anhydride, succinic anhydride and maleic anhydride; dicyandiamide, guanidines, 2-methylimidazole; An anionic curing agent of epoxy resin such as ethyl-4-methylimidazole can be used. In the self-crosslinking of the epoxy group, for example, imidazoles such as 2-methylimidazole and 2-ethyl-4-methylimidazole; anionic polymerization initiators such as 1,8-diazabicyclo (5,4,0) undecene-7 And cationic polymerization initiators such as sulfonium salts such as triphenylsulfonium hexafluorophosphate and diphenylsulfonium tetrafluoroborate, and diazonium salts such as phenyldiazonium hexafluorophosphate and phenyldiazonium tetrafluoroborate; Among these, a lignin compound is preferable in terms of reactivity.

  As a crosslinking agent in the case of using a lignin compound having an isocyanate group as a lignin derivative, a general curing agent for isocyanate resin may be used, for example, phenol resin, lignin decomposition product, polyvinyl alcohol, polyamine compound, and the like. Can be mentioned.

  As a crosslinking agent when a lignin compound having a vinyl group is used as the lignin derivative, a general vinyl group-containing compound polymerization initiator may be used. For example, anionic polymerization initiators such as butyl lithium and sodium ethoxide And radical polymerization initiators such as azobisisobutyronitrile (AIBN) and benzoyl peroxide (BPO).

  As a lignin derivative, a crosslinking agent in the case of using a lignin compound having an ethynyl group may be a polymerization catalyst of a general ethynyl group-containing compound, such as molybdenum pentachloride, tungsten pentachloride and norbornadiene rhodium chloride dimer. Can be mentioned.

  As a lignin derivative, the crosslinking agent in the case of using a lignin compound having a maleimide group may be a general polymerization initiator of a maleimide group-containing compound, such as a peroxide such as BPO and the anionic polymerization initiator. And so on.

  As the lignin derivative, the crosslinking agent in the case of using a lignin compound having a cyanate group may be a general polymerization catalyst of a cyanate group-containing compound, and examples thereof include metal catalysts such as cobalt naphthenate. .

  The lignin resin composition obtained by the present invention preferably uses 40 to 95 parts by weight of lignin compound, and more preferably 50 to 90 parts by weight. The crosslinking agent is preferably used in an amount of 5 to 60 parts by weight, and more preferably 10 to 50 parts by weight.

In addition to the above components, the lignin resin composition obtained according to the present invention optionally includes, as a curing accelerator, an alkali metal salt such as methoxy sodium and t-butoxy potassium; an alkaline earth metal salt such as calcium acetate; Na ₂ Alkali metal oxides such as O and K ₃ O ₂ ; Alkaline earth metal oxides such as CaO and BaO; and the like can be used. In the case of a lignin compound having an epoxy group as a lignin derivative, imidazoles such as 2-methylimidazole and 2-ethyl-4-methylimidazole; 1,8-diazabicyclo (5,4,0) undecene-7, tris (dimethyl Tertiary amines such as aminomethyl) phenol and benzyldimethylamine; triphenylphosphine, tetra-n-butylphosphonium tetraphenylborate and the like can be used. In the case of a lignin derivative having a vinyl group, an ethynyl group, a maleimide group, a cyanate group, or the like as a reactive group, the polymerization initiator can be used.
Furthermore, the additive mentioned later can be used as another component.

  As a manufacturing method of the lignin resin composition of this invention, a lignin compound, a hardening | curing agent, and the hardening accelerator can be obtained by mixing uniformly using a mixer in a predetermined amount. If necessary, these mixtures can be used at a temperature lower than the temperature at which the resin composition is cured, for example, using a hot plate, a kneader such as a pressure kneader, a roll, a kneader, and a twin screw extruder, or the like. Depending on the temperature, it may be heated, melted and mixed at about 50 to 100 ° C.

The molding material manufactured from the lignin resin composition obtained by this invention contains the said lignin resin composition and a filler.
Examples of the filler include inorganic fillers such as fused silica, crystalline silica, clay, alumina, mica, and glass fiber, and organic fillers such as wood powder, pulp, crushed cloth, and thermosetting resin cured powder. One or more of these can be used, but is not limited thereto.

  In the molding material obtained from the present invention, the content of the lignin resin composition and the filler is preferably 10 to 900 parts by weight, more preferably 20 to 500 parts by weight with respect to 100 parts by weight of the lignin resin composition. .

  In addition to the above components, the molding material obtained from the present invention optionally includes silane coupling agents such as epoxy silane, mercapto silane, amino silane, alkyl silane, ureido silane, and vinyl silane, titanate coupling agents, and aluminum coupling agents. Coupling agents such as aluminum / zirconium coupling agents; Colorants such as carbon black and bengara; Synthetic waxes such as polyethylene wax, higher fatty acid esters, fatty acid amides, ketones / amines and hydrogenated oil, paraffin wax, montan wax And natural waxes such as stearic acid, higher fatty acids such as stearic acid and zinc stearate and release agents such as metal salts thereof or paraffin; silicone oil and components for reducing stress such as silicone rubber; antimony trioxide, hydroxylated Inorganic ion exchangers, such as bismuth oxide hydrate; aluminum, magnesium hydroxide, zinc borate, flame retardants such as zinc molybdate and phosphazene, etc., be suitably blended a variety of additives no problem.

  In this invention, when using a mold release agent, it is preferable to use 0.01-10 weight part with respect to 100 weight part of lignin compounds, and it is more preferable to use 0.1-5 weight part. Although it can be used outside the above range, if it is less than 0.01 parts by weight, the releasability may be insufficient, and if it exceeds 10 parts by weight, the curability may be lowered.

  As a method for producing the molding material obtained from the present invention, for example, the above lignin resin composition, filler, and optionally other components can be uniformly mixed in a predetermined amount using a mixer. Can do. By the same method as that for the resin composition, it is obtained by heating and mixing, mixing, etc., if necessary, and pulverizing after cooling.

In the present invention, the resin composition and the resin molding material which have been described so far are subjected to a molding method such as transfer molding, injection molding and compression molding at a temperature of about 150 to 220 ° C. for about 1 to 5 minutes, It can be molded by heating to form a molded product. These molding temperatures and times are appropriately adjusted according to the purpose.
Examples of the molded article include electronic parts, electric parts, mechanical parts, and the like for semiconductor use, aircraft use, automobile use, industrial machine use, and the like.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these at all.

(Manufacture of lignin degradation products)
<Example 1>
Into a 300 ml pressure vessel, 15 g of Somune bamboo powder (60 mesh under) and 80 g of pure water were introduced, and the contents were stirred at 300 rpm and treated at a pressure of 1.6 MPa and 200 ° C. for 120 minutes to decompose Somune bamboo. Subsequently, 10.0 g of water-insoluble parts were separated by filtering the decomposition product and washing with pure water. This water-insoluble part was immersed in 200 ml of acetone for 12 hours and filtered to recover the acetone-soluble part. Subsequently, acetone was distilled off from the acetone-soluble part, followed by drying to obtain 3.2 g of a lignin decomposition product. ^From the results measured by ¹ H-NMR, an aromatic ring was observed at 7 to 8 ppm, a methoxy group was observed at around 3.5 to 4 ppm, and an alkyl group peak was observed at 0.5 to 3 ppm, confirming that the product was a lignin decomposition product. .

  The hydroxyl equivalent of the lignin degradation product obtained above was determined by the following method. In a stoppered Erlenmeyer flask, 4.0 g of a mixed solution of acetic anhydride / pyridine (1/3 volume ratio) and 1.0 g of the lignin decomposition product obtained above were dissolved. After maintaining this solution at 60 ° C. for 3 hours, 1 ml of pure water was added. When the solution thus obtained was titrated with a 0.1 mol / L NaOH aqueous solution with pH = 10 as an end point, the hydroxyl equivalent of the lignin decomposition product was 118.

Moreover, the molar ratio (hereinafter referred to as P / A ratio) between the phenolic hydroxyl group and the alcoholic hydroxyl group in the lignin decomposition product obtained above was determined by the following method. 1.0 g of the lignin degradation product obtained above was acetylated using 4.0 g of a mixed solution of acetic anhydride / pyridine (1/3 volume ratio). From this reaction solution, unreacted acetic anhydride and pyridine were distilled off, followed by measurement by ¹ H-NMR using an acetylated lignin decomposition product obtained by drying. From the integral ratio of protons derived from acetyl groups (derived from acetyl groups bonded to phenolic hydroxyl groups: 2.2 to 2.6 ppm, derived from acetyl groups bonded to alcoholic hydroxyl groups: 1.6 to 2.2 ppm), the molar ratio is determined. When determined, the P / A ratio was 8.9: 1.1.

  The softening point of the lignin degradation product obtained above was 95 ° C. when measured using a ring-and-ball softening point tester (ASP-MG2 manufactured by Meltech Co., Ltd.) according to JIS K2207. .

  The molecular weight of the lignin degradation product obtained above was measured by polystyrene-permeated gel permeation chromatography using tetrahydrofuran as an eluent. The number average molecular weight (Mn) = 1000 and the molecular weight distribution (Mw / Mn) = 2. .02.

(Manufacture of resin composition)
9 parts by weight of hexamethylenetetramine was mixed at room temperature with 91 parts by weight of the lignin decomposition product obtained by repeating the production of the lignin decomposition product to obtain a lignin resin composition.

<Example 2>
49 parts by weight of a lignin degradation product obtained by the same operation as in the production of the lignin degradation product in Example 1, 42 parts by weight of a novolak type phenol resin (softening point: 105 ° C., hydroxyl equivalent: 104), 9 parts by weight of hexamethylenetetramine The parts were mixed at room temperature to obtain a lignin resin composition.

<Example 3>
In Example 1, it carried out like Example 1 except having changed processing temperature 200 ° C in manufacture of a lignin decomposition product into 300 ° C, and obtained 3.6 g of lignin decomposition products. The lignin degradation product obtained here was evaluated in the same manner as in Example 1. As a result, hydroxyl equivalent = 171, P / A ratio = 8.5: 1.5, softening point 88 ° C., Mn = 570, Mw / Mn = 1.24.
9 parts by weight of hexamethylenetetramine was mixed at room temperature with 91 parts by weight of the lignin decomposition product obtained by repeating the production of the lignin decomposition product to obtain a lignin resin composition.

<Example 4>
Similar to Example 3, a lignin degradation product was obtained in the same manner as in Example 1 except that the treatment temperature 200 ° C. in the production of the lignin degradation product was changed to 300 ° C. 49 parts by weight of a lignin decomposition product obtained by repeating this process, 42 parts by weight of a novolac-type phenol resin (softening point: 105 ° C., hydroxyl equivalent: 104) and 9 parts by weight of hexamethylenetetramine were mixed at room temperature to obtain a lignin resin. A composition was obtained.

<Example 5>
In Example 1, it carried out like Example 1 except having changed processing temperature 200 ° C in manufacture of a lignin decomposition product into 150 ° C, and obtained 3.5 g of lignin decomposition products. The lignin degradation product obtained here was evaluated in the same manner as in Example 1. As a result, hydroxyl equivalent = 122, P / A ratio = 8.1: 1.9, softening point 121 ° C, Mn = 1800, Mw / Mn = 1.82.
9 parts by weight of hexamethylenetetramine was mixed at room temperature with 91 parts by weight of the lignin decomposition product obtained by repeating the production of the lignin decomposition product to obtain a lignin resin composition.

<Example 6>
Similar to Example 5, a lignin degradation product was obtained in the same manner as in Example 1 except that the treatment temperature 200 ° C. in the production of the lignin degradation product was changed to 150 ° C. 49 parts by weight of a lignin decomposition product obtained by repeating this process, 42 parts by weight of a novolac-type phenol resin (softening point: 105 ° C., hydroxyl equivalent: 104) and 9 parts by weight of hexamethylenetetramine were mixed at room temperature to obtain a lignin resin. A composition was obtained.

(Production of lignin derivatives)
<Example 7>
To a 100 ml three-necked flask equipped with a stirrer, a condenser and a dropping funnel, 1.2 g of the lignin decomposition product obtained in the same manner as in Example 1 and 100.0 g of epichlorohydrin were added, and the pressure was 133 hPa. Then, 2.0 g of a 20% strength aqueous NaOH solution was added dropwise over 30 minutes while refluxing under reduced pressure. Thereafter, the vacuum reflux state was maintained for 90 minutes to obtain a reaction mixture. In the reaction mixture, the insoluble part was removed by filtration, and the epichlorohydrin soluble part was isolated. Epichlorohydrin was distilled off from this epichlorohydrin soluble portion and dried to obtain 0.8 g of a lignin derivative having an epoxy group.
When the structure of the lignin derivative having an epoxy group obtained above was confirmed by ¹ H-NMR, it was found to be 2.7, 2.9, 3.3, 3.5, 3.9 ppm in addition to the peak of the lignin decomposition product. An epoxy group-derived peak was observed.
The molecular weight of the lignin derivative having an epoxy group was Mn = 950 and Mw / Mn = 3.67 as measured by gel permeation chromatography in terms of polystyrene.
The epoxy equivalent of the lignin derivative having an epoxy group was 390 as measured by ¹ H-NMR.

(Manufacture of resin composition)
To 79 parts by weight of the lignin derivative having an epoxy group obtained by repeating the above-described production process of the lignin derivative, 21 parts by weight of a novolak type phenol resin (softening point: 105 ° C., hydroxyl equivalent: 104) and 1 part by weight of triphenylphosphine were added. The mixture was mixed at room temperature to obtain a lignin resin composition.

<Example 8>
50 parts by weight of a lignin derivative having an epoxy group obtained by repeating the same operation as in the production of the lignin derivative in Example 7, 25 parts by weight of a novolac type phenol resin (softening point: 105 ° C., hydroxyl group equivalent: 104), orthocresol 25 parts by weight of a novolac epoxy resin (softening point: 65 ° C., epoxy equivalent: 210) and 1 part by weight of triphenylphosphine were mixed at room temperature to obtain a lignin resin composition.

<Example 9>
23 parts by weight of a lignin derivative having an epoxy group obtained by repeating the same operation as the production of the lignin derivative in Example 7 and 77 parts by weight of the lignin derivative obtained by repeating the same operation as the production of the lignin degradation product in Example 1 1 part by weight of triphenylphosphine was mixed at room temperature to obtain a lignin resin composition.

<Example 10>
100 parts by weight of an lignin derivative having an epoxy group obtained by repeating the same operations as in the production of the lignin derivative in Example 7 and 2 parts by weight of 2-methylimidazole were mixed at room temperature to obtain a lignin resin composition.

<Example 11>
In Example 7, except that the lignin degradation product was changed to that obtained in Example 3, the same procedure as in Example 7 was performed to obtain 0.9 g of a lignin derivative having an epoxy group. The lignin derivative having an epoxy group obtained here was evaluated in the same manner as in Example 7. As a result, the molecular weight was measured by gel permeation chromatography in terms of polystyrene, and Mn = 750 and Mw / Mn = 2.89. Met.
The epoxy equivalent of the lignin derivative having an epoxy group was 540 as measured by ¹ H-NMR.

(Manufacture of resin composition)
To 84 parts by weight of an lignin derivative having an epoxy group obtained by repeating the above-described production process of lignin derivative, 16 parts by weight of phenol novolak having a hydroxyl equivalent weight of 104 at 105 ° C. and 1 part by weight of triphenylphosphine are mixed at room temperature. Thus, a lignin resin composition was obtained.

<Example 12>
60 parts by weight of a lignin derivative having an epoxy group obtained by repeating the same operations as in the production of the lignin derivative in Example 11, 20 parts by weight of a novolac type phenol resin (softening point: 105 ° C., hydroxyl group equivalent: 104), orthocresol 20 parts by weight of a novolac epoxy resin (softening point: 65 ° C., epoxy equivalent: 210) and 1 part by weight of triphenylphosphine were mixed at room temperature to obtain a lignin resin composition.

<Example 13>
24 parts by weight of a lignin derivative having an epoxy group obtained by repeating the same operation as the production of the lignin derivative in Example 11 and 76 parts by weight of the lignin derivative obtained by repeating the same operation as the production of the lignin degradation product in Example 3 1 part by weight of triphenylphosphine was mixed at room temperature to obtain a lignin resin composition.

<Example 14>
100 parts by weight of a lignin derivative having an epoxy group obtained by the same operation as in the production of a lignin derivative in Example 11 and 2 parts by weight of 2-methylimidazole were mixed at room temperature to obtain a lignin resin composition.

<Example 15>
In Example 7, except having changed the lignin decomposition product into what was obtained in Example 5, it carried out similarly to Example 7 and obtained 0.7g of lignin derivatives which have an epoxy group. The lignin derivative having an epoxy group obtained here was evaluated in the same manner as in Example 7. As a result, the molecular weight was Mn = 2000 and Mw / Mn = 3.47.
The epoxy equivalent of the lignin derivative having an epoxy group was 620 as measured by ¹ H-NMR.

(Manufacture of resin composition)
To 86 parts by weight of the lignin derivative having an epoxy group obtained by repeating the above-described operation of producing the lignin derivative, 14 parts by weight of a novolak type phenol resin (softening point: 105 ° C., hydroxyl equivalent: 104) and 1 part by weight of triphenylphosphine were added. The mixture was mixed at room temperature to obtain a lignin resin composition.

<Example 16>
44 parts by weight of a lignin derivative having an epoxy group obtained by the same operation as in the production of the lignin derivative in Example 15, 28 parts by weight of phenol novolac having a softening point of 105 ° C. and a hydroxyl equivalent of 104, and an epoxy equivalent of 65 ° C. 210 parts by weight of orthocresol novolac epoxy resin 210 and 1 part by weight of triphenylphosphine were mixed at room temperature to obtain a lignin resin composition.

<Example 17>
16 parts by weight of an lignin derivative having an epoxy group obtained by repeating the same operation as the production of the lignin derivative in Example 15 and 84 parts by weight of the lignin derivative obtained by repeating the same operation as the production of the lignin degradation product in Example 5 1 part by weight of triphenylphosphine was mixed at room temperature to obtain a lignin resin composition.

<Example 18>
100 parts by weight of an lignin derivative having an epoxy group obtained by the same operation as in the production of the lignin derivative in Example 15 and 2 parts by weight of 2-methylimidazole were mixed at room temperature to obtain a lignin resin composition.

<Comparative Example 1>
(Production of lignophenol derivatives)
In accordance with Non-Patent Document 1 (K. Mikame, M. Funoka, Polym. J., 38, 585-591, 2006J), a lignophenol derivative was synthesized by the following method.
Take 10 g of Somune bamboo powder in a 500 ml beaker, add acetone solution of p-cresol (containing 3 mol times phenol derivative per lignin constituent unit), stir with a glass rod and let stand for 24 hours. Thereafter, acetone was completely distilled off to obtain p-cresol-adsorbed wood flour. To this bamboo powder, 100 ml of 72 wt% sulfuric acid was added, and the mixture stirred vigorously at 30 ° C. for 1 hour was recovered from a solution in which a large excess of water was added. A lignophenol derivative was obtained. When this lignophenol derivative was evaluated in the same manner as in Example 1, Mn = 3600, OH equivalent = 143 g / eq, and P / A ratio = 5.8: 4.2.

(Manufacture of resin composition)
8 parts by weight of hexamethylenetetramine was mixed with 92 parts by weight of a lignophenol derivative obtained by repeating the above-described operation for producing a lignophenol derivative at room temperature to obtain a thermosetting resin composition.

<Comparative example 2>
(Production of lignophenol derivatives)
According to Non-Patent Document 2 (Kadota, K. Hasegawa, M. Funoka Journal of Network Polymer. Japan, 27, 118-125, 2006), the lignophenol derivative obtained in Comparative Example 1 was epoxidized by the following method. . A 100 ml three-necked flask equipped with a stirrer, a condenser and a dropping funnel was charged with 1.4 g of lignophenol derivative and 100.0 g of epichlorohydrin obtained in the same manner as in Comparative Example 1, and the pressure was reduced to 133 hPa. While refluxing, 1.0 g of a 20% NaOH aqueous solution was added dropwise over 30 minutes. Thereafter, the vacuum reflux state was maintained for 90 minutes. The insoluble part was filtered off from the reaction mixture, and epichlorohydrin was distilled away from the epichlorohydrin soluble part and dried to obtain 1.3 g of epoxidized lignophenol. When the obtained lignophenol derivative having an epoxy group was evaluated in the same manner as in Example 7, Mn = 2400 and the epoxy equivalent was 790.

(Manufacture of resin composition)
To 88 parts by weight of the lignophenol derivative having an epoxy group obtained by repeating the above-described operation for producing the lignophenol derivative, 12 parts by weight of phenol novolac having a softening point of 105 ° C. and a hydroxyl group equivalent of 104 and 1 part by weight of triphenylphosphine were added at room temperature. To obtain a thermosetting resin composition.

(Manufacture of molding materials)
<Example 19>
100 parts by weight of the same lignin resin composition as in Example 1 and 300 parts by weight of crushed fused silica (average particle size 10 μm) were blended and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 20>
100 parts by weight of the same lignin resin composition as in Example 2 and 300 parts by weight of crushed fused silica (average particle size 10 μm) were blended and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 21>
100 parts by weight of the same lignin resin composition as in Example 3 and 300 parts by weight of crushed fused silica (average particle size: 10 μm) were blended and kneaded at 90 ° C. for 5 minutes to obtain a molding material.

<Example 22>
100 parts by weight of the same lignin resin composition as in Example 4 and 300 parts by weight of crushed fused silica (average particle size 10 μm) were blended and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 23>
100 parts by weight of the same lignin resin composition as in Example 5 and 300 parts by weight of crushed fused silica (average particle size 10 μm) were blended and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 24>
100 parts by weight of the same lignin resin composition as in Example 6 and 300 parts by weight of crushed fused silica (average particle size 10 μm) were blended and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 25>
101 parts by weight of the same lignin resin composition as in Example 7 and 300 parts by weight of crushed fused silica (average particle size: 10 μm) were blended and kneaded at 90 ° C. for 5 minutes to obtain a molding material.

<Example 26>
101 parts by weight of the same lignin resin composition as in Example 8 and 300 parts by weight of crushed fused silica (average particle size: 10 μm) were blended and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 27>
300 parts by weight of crushed fused silica (average particle size 10 μm) was blended with 101 parts by weight of the same lignin resin composition as in Example 9, and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 28>
300 parts by weight of crushed fused silica (average particle size 10 μm) was blended with 102 parts by weight of the same lignin resin composition as in Example 10, and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 29>
300 parts by weight of crushed fused silica (average particle size: 10 μm) was blended with 101 parts by weight of the same lignin resin composition as in Example 11 and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 30>
300 parts by weight of crushed fused silica (average particle size: 10 μm) was blended with 101 parts by weight of the same lignin resin composition as in Example 12, and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 31>
300 parts by weight of crushed fused silica (average particle size 10 μm) was blended with 101 parts by weight of the same lignin resin composition as in Example 13, and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 32>
300 parts by weight of crushed fused silica (average particle size: 10 μm) was blended with 102 parts by weight of the same lignin resin composition as in Example 14, and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 33>
300 parts by weight of crushed fused silica (average particle size 10 μm) was blended with 101 parts by weight of the same lignin resin composition as in Example 15, and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 34>
300 parts by weight of crushed fused silica (average particle size 10 μm) was blended with 101 parts by weight of the same lignin resin composition as in Example 16, and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 35>
300 parts by weight of crushed fused silica (average particle size: 10 μm) was blended with 101 parts by weight of the same lignin resin composition as in Example 17, and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Example 36>
300 parts by weight of crushed fused silica (average particle size 10 μm) was blended with 102 parts by weight of the same lignin resin composition as in Example 18, and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

<Comparative Example 3>
9 parts by weight of hexamethylenetetramine and 300 parts by weight of crushed fused silica (average particle size 10 μm) are blended with 92 parts by weight of a lignophenol derivative obtained by the same operation as in Comparative Example 1, and kneaded with a hot roll at 90 ° C. for 5 minutes. Thus, a molding material was obtained.

<Comparative example 4>
To 88 parts by weight of a lignophenol derivative having an epoxy group obtained by the same operation as in Comparative Example 2, 12 parts by weight of a novolac type phenol resin (softening point: 105 ° C., hydroxyl equivalent: 104), crushed fused silica (average particle diameter) 10 μm) 300 parts by weight and 1 part by weight of triphenylphosphine were blended and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a molding material.

(Evaluation of resin composition and molding material)
Table 1 shows the results of evaluating the maximum torque of the curast meter by the following measurement method for the purpose of evaluating the curing characteristics of the resin compositions obtained in Examples 1 to 18 and Comparative Examples 1 and 2. .
Table 2 shows the results of evaluation of the Barcol hardness using the molding materials obtained in Examples 19 to 36 and Comparative Examples 3 and 4 by the following measuring method.

Curast meter measurement method Approximately 4.3 g of the resin composition to be subjected to the test is taken, and the measurement temperature is 175 ° C. and the amplitude angle is 1 ° using a curast meter (manufactured by Orientec Co., Ltd., JSR curast meter IV PS type). The torque change with time was measured. The maximum torque value obtained was read from the time course curve of the torque thus obtained.

Barcol hardness measurement method Using a water-absorbing disk manufacturing die according to JIS-K6911, after molding at 175 ° C. for 120 seconds, immediately take it out and leave it on a hot plate heated to 175 ° C. for 10 seconds. The time hardness was measured using a Barcol hardness tester (GYZJ935). It shows that sclerosis | hardenability is so high that this figure is large.

  From Table 1, the lignin resin composition obtained by this invention was excellent in the degree of hardening compared with the comparative example. According to Table 2, the molding material obtained by this invention was very excellent in sclerosis | hardenability compared with the comparative example.

  Since the lignin resin composition and molding material obtained by this invention are excellent in sclerosis | hardenability, they can be used conveniently for uses, such as an electrical component, an electronic component, and an automotive component.

Claims (3)

A method for producing a lignin resin composition comprising, as essential components, a lignin derivative formed by introducing an epoxy group into a phenolic hydroxyl group of a lignin compound obtained by decomposing biomass and a crosslinking agent,
A decomposition step of placing biomass in the presence of water and decomposing them under high temperature and high pressure;
An immersion step of immersing the insoluble matter in the processed product obtained by the decomposition step in a solvent in which lignin is soluble;
A distillation step for distilling off the solvent in which the lignin is soluble from the soluble matter in the treated product obtained by the immersion step;
A reactive group introduction step of mixing the treated product obtained by the distillation step and the compound containing the epoxy group ;
A cross-linking agent mixing step of mixing the processed product obtained by the reactive group introducing step and the cross-linking agent,
The said lignin compound is a manufacturing method of the lignin resin composition characterized by including phenolic hydroxyl group and alcoholic hydroxyl group by the ratio of 9: 1 to 8: 2 by molar ratio. The lignin resin composition according to claim 1 , wherein the decomposition step decomposes biomass in the presence of water at a processing temperature of 150 to 400 ° C, a processing pressure of 1.0 to 40 MPa, and a processing time of 480 minutes or less. Manufacturing method. The method for producing a lignin resin composition according to claim 1 or 2 , wherein the lignin resin composition has a lignin compound content of 40 to 95 wt% and a crosslinking agent content of 5 to 60 wt%.