JP2013227470A - Lignin resin composition and lignin resin molding material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lignin resin composition containing a component originated from plants as a main material, and excellent in flowability and mechanical characteristics after cured, and to provide a lignin resin molding material excellent in moldability and mechanical characteristics after cured.SOLUTION: A lignin resin composition comprises a lignin derivative obtained by degrading biomass, and a cross-linking agent containing a compound represented by formula (1) below. The lignin resin composition is preferably a resin composition obtained by degrading biomass in semicritical water, and more preferably a resin composition containing a latent catalyst differentiating the presence or absence of the cross-linking reaction of the cross-linking agent or the rate of the cross-linking reaction in response to temperature. Formula (1): Z-(CHOR), (wherein, Z is one of a melamine residue, urea residue, glycolyl residue, imidazolidinone residue and aromatic ring residue; m is an integer of 2-14; and Rs are each independently 1-4C alkyl or H).

Description

  The present invention relates to a lignin resin composition and a lignin resin molding material.

  Many wood-based waste materials (biomass) such as bark, thinned wood, and building waste have been disposed of so far. However, protection of the global environment is becoming an important issue, and from this point of view, the reuse and recycling of wood-based waste materials are being considered.

  Common woody main components are cellulose, hemicellulose and lignin. Among these, lignin contained at a ratio of about 30% has a structure containing abundant aromatic rings, phenolic hydroxyl groups, and alcoholic hydroxyl groups, and therefore, utilization as a resin raw material has been studied (for example, (See Patent Document 1).

  Thus, in order to utilize lignin as a resin raw material, it is necessary to isolate lignin from a wooden waste material.

  In Patent Document 1, a liquid phenol derivative is infiltrated into wood flour, lignin in wood flour is solvated with a phenol derivative, and then concentrated acid is added to dissolve the cellulose component, thereby dissolving lignin as a solvent. A method is disclosed in which a hydrated phenol derivative and a concentrated acid in which a cellulose component is dissolved are separated into two phases, and a lignin phenol derivative is extracted from the phenol derivative phase.

  Further, in Patent Document 1, a solvent in which a phenol derivative is dissolved in wood flour is infiltrated, and then the solvent is distilled off. Thereafter, concentrated acid is added to the remaining wood flour, thereby being solvated by the phenol derivative. A method for obtaining lignin is disclosed.

  And a thermosetting lignin resin composition is obtained by mixing the obtained lignin derivative and a crosslinking agent (for example, refer patent document 2). Patent Document 2 describes that the obtained lignin resin composition has excellent fluidity and can be used for the production of a molded body.

  For the production of the molded body, for example, a molding material containing a thermosetting lignin resin composition and a filler is used.

  However, when the molding material with a curing catalyst added to increase the amount of filler added or to shorten the molding time is subjected to low-pressure transfer molding, or when the shape of the molding die is complicated, the flow of the molding material It was necessary to further improve the performance.

JP 2001-261839 A JP 2009-227890 A

  An object of the present invention is to provide a lignin resin composition having a plant-derived component as a main material and having excellent fluidity and mechanical properties after curing, and a lignin resin molding material having excellent moldability and mechanical properties after curing. It is to provide.

Such an object is achieved by the present inventions (1) to (14) below.
(1) A lignin resin composition comprising a lignin derivative obtained by decomposing biomass and a crosslinking agent containing a compound represented by the following formula (1).
_{Z- (CH 2 OR) m (} 1)
[Z in Formula (1) is any one of a melamine residue, a urea residue, a glycolyl residue, an imidazolidinone residue, and an aromatic ring residue. Moreover, m represents the integer of 2-14. R is independently an alkyl group having 1 to 4 carbon atoms or a hydrogen atom. However, -CH 2 _OR, the nitrogen atom of the melamine residues, the nitrogen atom of the primary amino groups of the urea residues, the nitrogen atom of the secondary amino group of the glycolyl residues, the secondary amino group of the imidazolidinone residues It is directly bonded to either the nitrogen atom or the carbon atom of the aromatic ring residue. ]

［式（２）中、ＸはＣＨ_２ＯＲまたは水素原子であり、Ｒは独立して炭素数１〜４のアルキル基または水素原子である。また、ｎは１〜３の整数を表す。］

［式（３）中、Ｒは独立して炭素数１〜４のアルキル基または水素原子である。］

［式（４）中、Ｒは独立して炭素数１〜４のアルキル基または水素原子である。］

［式（５）中、Ｒは独立して炭素数１〜４のアルキル基または水素原子である。］ (2) The said compound is a lignin resin composition as described in said (1) which is represented by either of following formula (2)-(5).

[In the formula (2), X is _CH 2 OR or a hydrogen atom, R is independently an alkyl group or a hydrogen atom having 1 to 4 carbon atoms. N represents an integer of 1 to 3. ]

[In Formula (3), R is a C1-C4 alkyl group or a hydrogen atom independently. ]

[In Formula (4), R is a C1-C4 alkyl group or a hydrogen atom independently. ]

[In Formula (5), R is a C1-C4 alkyl group or a hydrogen atom independently. ]

［式（６）中、ｎは１〜３の整数を表す。］

［式（７）中、ｎは１〜３の整数を表す。］ (3) The lignin resin composition according to (2), wherein the compound is a compound represented by the following formula (6) or (7).

[In Formula (6), n represents the integer of 1-3. ]

[In formula (7), n represents the integer of 1-3. ]

  (4) A lignin resin composition comprising a lignin derivative obtained by decomposing biomass and a crosslinking agent containing at least one of quinuclidine and pyridine.

  (5) The lignin resin composition according to any one of (1) to (4), wherein the lignin derivative is obtained by decomposing biomass under subcritical water.

  (6) The lignin resin composition according to (5), wherein the lignin derivative is a product obtained by further decomposing biomass under subcritical water and further methylolating.

  (7) The lignin resin composition according to any one of (1) to (6), further including a latent catalyst that varies the presence or absence of the crosslinking reaction or the speed of the crosslinking reaction depending on the temperature. Lignin resin composition.

  (8) The lignin resin composition according to any one of (1) to (7), further including a compound that releases an acidic substance by heating.

  (9) The lignin resin composition according to (8), wherein the compound that releases an acidic substance is a compound that releases an acidic substance having a dissociation constant pKa of 2 or less by heating.

  (10) The lignin resin composition according to (9), wherein the compound that releases the acidic substance is a compound that releases an acidic substance having a dissociation constant pKa of 2 or less by heating at 120 to 150 ° C.

  (11) The lignin resin composition according to any one of (8) to (10), wherein the compound that releases the acidic substance is cyclohexyl aromatic sulfonate.

  (12) The lignin resin composition according to the above (11), wherein the cyclohexyl aromatic sulfonate is cyclohexyl benzene sulfonate.

  (13) The cyclohexyl benzenesulfonates are cyclohexyl = 4-methylbenzenesulfonate, 3-methylcyclohexyl = 4-methylbenzenesulfonate, 3,5-dimethylcyclohexyl = 4-methylbenzenesulfonate, 4-butylcyclohexyl = 4- At least one selected from the group consisting of methylbenzenesulfonate, 2-isopropyl-5-methylcyclohexyl = 4-methylbenzenesulfonate, 2-hydroxycyclohexyl = 4-methylbenzenesulfonate and 4-hydroxycyclohexyl = 4-methylbenzenesulfonate The lignin resin composition as described in (12) above.

  (14) A lignin resin molding material comprising the lignin resin composition according to any one of (1) to (13) above and a filler.

  According to the present invention, a lignin resin composition having a plant-derived component as a main material and excellent in fluidity and mechanical properties after curing can be obtained.

  Further, according to the present invention, a lignin resin molding material having a plant-derived component as a main material and excellent in moldability and mechanical properties after curing can be obtained.

  Hereinafter, the lignin resin composition and the lignin resin molding material of the present invention will be described in detail based on preferred embodiments.

<Lignin resin composition and lignin resin molding material>
The lignin resin composition of this invention contains the lignin derivative obtained by decomposing | disassembling biomass, and the crosslinking agent containing the compound mentioned later.

  Moreover, the lignin resin molding material of this invention contains the said lignin resin composition, and is used for obtaining a resin molded product by shape | molding by various shaping | molding methods.

  Such a lignin resin molding material has high fluidity because of its low melt viscosity. For example, it has excellent moldability (shape transferability) when molded by various molding methods and excellent mechanical properties after curing. It will be. For this reason, when the shape of the mold is complicated, when the amount of filler added is large, or when a curing catalyst is added, a resin molded product with high dimensional accuracy and excellent mechanical properties can be produced. . Moreover, since the lignin resin composition has a high impregnation property with respect to the core material and can form a rigid structure after curing, a laminate having excellent durability and appearance can be produced.

  Hereinafter, each component of the lignin resin composition and the lignin resin molding material will be sequentially described.

(Lignin derivative)
First, the lignin derivative will be described. Lignin, together with cellulose and hemicellulose, is a major component that forms the skeleton of plants and is one of the most abundant substances in nature. A lignin derivative is a compound having a phenol derivative as a unit structure, and this unit structure has a chemically and biologically stable carbon-carbon bond or carbon-oxygen-carbon bond. It is difficult to undergo manual decomposition. For this reason, a lignin derivative is useful as a resin raw material.

  The lignin derivative used in the present invention is obtained by decomposing biomass. Biomass is a plant or a processed product of a plant, and these are formed by capturing and fixing carbon dioxide in the atmosphere in the process of photosynthesis, and thus contribute to the suppression of the increase in carbon dioxide in the atmosphere. For this reason, it can contribute to suppression of global warming by utilizing biomass industrially.

  Specific examples of the lignin derivative include a guaiacylpropane structure represented by the following formula (8), a syringylpropane structure represented by the following formula (9), and a 4-hydroxyphenylpropane structure represented by the following formula (10). Can be mentioned. From conifers, mainly guaiacylpropane structures, from broadleaf trees, mainly guaiacylpropane structures and syringylpropane structures, and from herbs, mainly guaiacylpropane structures, syringylpropane structures, and 4-hydroxy Each phenylpropane structure is extracted.

  Moreover, the lignin derivative in the present invention is preferably one in which at least one of the ortho-position and para-position of the aromatic ring is unsubstituted with respect to the hydroxyl group. Such a lignin derivative is excellent in reactivity because it contains a large number of reaction sites where a curing agent acts due to electrophilic substitution reaction on the aromatic ring and steric hindrance can be reduced in the reaction with a hydroxyl group.

  In addition to the above basic structure, the lignin derivative may be a lignin derivative having a functional group introduced (lignin secondary derivative).

  The functional group possessed by the lignin secondary derivative is not particularly limited, but for example, those in which two or more of the same functional groups can react with each other or those capable of reacting with other functional groups are suitable. Specific examples include an epoxy group, a methylol group, a vinyl group having a carbon-carbon unsaturated bond, an ethynyl group, a maleimide group, a cyanate group, and an isocyanate group. Of these, a lignin derivative having a methylol group introduced (methylolated) is preferably used. Such a lignin secondary derivative is self-cross-linked by a self-condensation reaction between methylol groups and reliably cross-links to an alkoxymethyl group or a hydroxyl group in the cross-linking agent. As a result, a cured product having a particularly homogeneous and rigid skeleton and excellent mechanical properties can be obtained.

  In addition, the lignin derivative in the present invention preferably has a polystyrene-equivalent number average molecular weight of 200 to 2000 as measured by gel permeation chromatography, and more preferably 300 to 1800. Such a lignin derivative having a number average molecular weight has a higher balance between reactivity (curability) and meltability or solubility. Therefore, a lignin resin molding material having both high mechanical properties and moldability after curing can be obtained.

In addition, the lignin derivative in the present invention, when subjected to ¹ H-NMR analysis, in the obtained chemical shift spectrum, the integrated value of the peak attributed to the aromatic proton is the integrated value of the peak attributed to the aliphatic proton. Is preferably about 15 to 50%, more preferably about 15 to 45%, still more preferably about 20 to 40%, and particularly preferably about 20 to 35%. Thereby, the reactivity which contributes to the mechanical characteristic of the crosslinked resin of a lignin derivative and the meltability which contributes to the moldability of a molding material, or the solubility to a solvent can be made compatible more highly. As a result, a resin molded product having high dimensional accuracy and excellent mechanical properties can be obtained.

  When the ratio is lower than the lower limit, the reaction site for causing a crosslinking reaction or the reaction site for introducing a reactive group is substituted with an aliphatic group and the number of crosslinking reaction points is reduced, so that the lignin derivative is crosslinked. When this is done, the physical properties of the crosslinked product may be reduced. On the other hand, when the ratio exceeds the upper limit, the meltability of the lignin derivative or the solubility in a solvent is lowered, and the moldability of the molding material containing the lignin derivative may be lowered.

In addition, since aromatic protons and aliphatic protons generate peaks at distant positions in the chemical shift spectrum of ¹ H-NMR analysis, peaks can be separated, and peak identification and integral calculation are performed. be able to.

  Specifically, when tetramethylsilane is used as a reference substance for analysis, generally, a peak attributed to an aromatic proton is located in the vicinity of 6 to 8 ppm. In addition, the peak attributed to the aliphatic proton is located in the vicinity of 0.5 to 5 ppm.

  Note that the integrated value of the peak attributed to the aromatic proton and the integrated value of the peak attributed to the aliphatic proton described above can be adjusted according to the biomass treatment conditions. For example, it is considered that the integrated value of the peak attributed to aromatic protons tends to increase by increasing the processing temperature and processing pressure of biomass or increasing the processing time.

(Crosslinking agent)
Next, the crosslinking agent will be described.

  Although the crosslinking agent contained in the lignin resin composition of this invention will not be specifically limited if a lignin derivative can be bridge | crosslinked, What contains the compound represented by following formula (1) is preferable.

_{Z- (CH 2 OR) m (} 1)
[Z in Formula (1) is any one of a melamine residue, a urea residue, a glycolyl residue, an imidazolidinone residue, and an aromatic ring residue. Moreover, m represents the integer of 2-14. R is independently an alkyl group having 1 to 4 carbon atoms or a hydrogen atom. However, -CH 2 _OR, the nitrogen atom of the melamine residues, the nitrogen atom of the primary amino groups of the urea residues, the nitrogen atom of the secondary amino group of the glycolyl residues, the secondary amino group of the imidazolidinone residues It is directly bonded to either the nitrogen atom or the carbon atom of the aromatic ring residue. ]

  The lignin resin composition containing such a compound is excellent in mechanical properties after curing, and contributes to improvement in durability and appearance of the cured product. This is because the compound represented by the above formula (1) contained in the cross-linking agent can form a polyfunctional cross-linking point, so that the lignin derivative is cross-linked with high density and uniformity to form a homogeneous and rigid skeleton. It is because it forms. The rigid skeleton improves the mechanical properties and durability (boiling resistance, etc.) of the cured product, and also suppresses the occurrence of blisters and cracks, thereby improving the appearance of the cured product.

  Moreover, the said crosslinking agent has a self-hardening property, and can form a co-crosslinking structure between lignin derivatives. For this reason, the hardened | cured material formed by shape | molding and hardening the lignin resin molding material containing such a lignin resin composition has the compatibility with a lignin derivative and a crosslinking agent, and homogeneity becomes high. Therefore, the blending ratio can be optimized from the viewpoint of achieving both the moldability of the lignin resin molding material and the mechanical properties of the cured product, and a resin molded product having excellent dimensional accuracy and mechanical properties can be obtained.

  Further, since the volatile component is moderately generated during the crosslinking reaction, the crosslinking agent can suppress problems such as blisters and cracks that occur when the volatile component is released to the outside of the cured product. As a result, a resin product excellent in appearance can be obtained.

  In addition, the said crosslinking agent contributes to the improvement of the moldability of a lignin resin molding material. This is because the melting point of the cross-linking agent is low, the viscosity of the molding material is lowered during heating, and the cross-linking agent is relatively slow cross-linking, and the cross-linking reaction proceeds gradually when heated. it is conceivable that.

In addition, as described above, —CH ₂ OR is a nitrogen atom of a melamine residue, a nitrogen atom of a primary amino group of a urea residue, a nitrogen atom of a secondary amino group of a glycolyl residue, or 2 of an imidazolidinone residue. It is directly bonded to either the nitrogen atom of the primary amino group or the carbon atom of the aromatic ring residue, but two or more “—CH ₂ OR” are bonded to the same nitrogen atom or carbon atom. In this case, it is preferable that “R” included in at least one of “—CH ₂ OR” is an alkyl group. Thereby, a lignin derivative can be bridge | crosslinked reliably.

  In this specification, the melamine residue refers to a group having a melamine skeleton represented by the following formula (A).

  In this specification, the urea residue refers to a group having a urea skeleton represented by the following formula (B).

  In this specification, the glycolyl residue refers to a group having a glycolyl skeleton represented by the following formula (C).

  In the present specification, the imidazolidinone residue refers to a group having an imidazolidinone skeleton represented by the following formula (D).

  In this specification, an aromatic ring residue refers to a group having an aromatic ring (benzene ring).

  Moreover, especially as a compound represented by the said Formula (1), the compound represented by either of following formula (2)-(5) is used preferably. These react with the crosslinking reaction point on the aromatic ring contained in the phenol skeleton in the lignin derivative to reliably crosslink the lignin derivative and cause self-crosslinking by self-condensation reaction between functional groups. As a result, a cured product having a particularly homogeneous and rigid skeleton and excellent in mechanical properties, durability and appearance can be obtained.

［式（２）中、ＸはＣＨ_２ＯＲまたは水素原子であり、Ｒは独立して炭素数１〜４のアルキル基または水素原子である。また、ｎは１〜３の整数を表す。］

[In the formula (2), X is _CH 2 OR or a hydrogen atom, R is independently an alkyl group or a hydrogen atom having 1 to 4 carbon atoms. N represents an integer of 1 to 3. ]

［式（３）中、Ｒは独立して炭素数１〜４のアルキル基または水素原子である。］

[In Formula (3), R is a C1-C4 alkyl group or a hydrogen atom independently. ]

［式（４）中、Ｒは独立して炭素数１〜４のアルキル基または水素原子である。］

[In Formula (4), R is a C1-C4 alkyl group or a hydrogen atom independently. ]

［式（５）中、Ｒは独立して炭素数１〜４のアルキル基または水素原子である。］

[In Formula (5), R is a C1-C4 alkyl group or a hydrogen atom independently. ]

  As the compound represented by the above formula (2), a compound represented by the following formula (6) or (7) is particularly preferably used. These react with a crosslinking reaction point on the aromatic ring contained in the phenol skeleton in the lignin derivative to particularly surely crosslink the lignin derivative and cause self-crosslinking by self-condensation reaction between functional groups. As a result, a cured product having a particularly uniform and rigid skeleton and excellent mechanical properties, durability and appearance can be obtained.

［式（６）中、ｎは１〜３の整数を表す。］

[In Formula (6), n represents the integer of 1-3. ]

［式（７）中、ｎは１〜３の整数を表す。］

[In formula (7), n represents the integer of 1-3. ]

  Specific examples of the compound represented by the above formula (1) include Sumikanol 507A (Taoka Chemical Industries), 2,4,6-tris [bis (methoxymethyl) amino] -1,3,5-triazine. (Manufactured by Tokyo Chemical Industry Co., Ltd.), Nikarak MW-30HM, Nikarak MW-390, Nikarak MW-100LM, Nikarak MX-750LM, Nikarak MX-290, Nikarak MX-280, Nikarak MX-270 (all manufactured by Sanwa Chemical), etc. Is mentioned.

  Among the compounds represented by the above formula (1), those in which Z is any one of a melamine residue, a urea residue, a glycolyl residue, and an imidazolidinone residue include, for example, JP-A-2005 And the compounds described in Chemical formula 16 and Chemical formula 18 of JP-A-43883.

  Among the compounds represented by the above formula (1), those in which Z is an aromatic ring residue include, for example, the compounds described in Chemical Formulas 21 to 26 of JP-A-2005-37925, And the compounds described in Chemical formula 17 of Kaikai 2005-43883.

On the other hand, the cross-linking agent may contain at least one compound of quinuclidine and pidgin instead of or together with the compound represented by the formula (1). A cured product containing such a cross-linking agent has excellent mechanical strength and high durability and appearance. This is because quinuclidine and pididine cross-link lignin derivatives at high density and uniformly to form a homogeneous and rigid skeleton.
In addition, when a proton from a lignin derivative is added to quinuclidine and pyridine, a carbocation is generated. This carbocation reacts with the lignin derivative to form a methylene bond. In this way, the homogeneous and rigid skeleton described above is formed.

  In addition, the crosslinking agent may contain a crosslinking agent component other than the above compound, but even in that case, the addition amount is set to be smaller than that of the above compound. Examples of the cross-linking agent component other than the above compound include, for example, orthocresol novolac epoxy resin, bisphenol A type epoxy resin, epoxidized glycerin, epoxidized linseed oil, epoxy resin such as epoxidized soybean oil, hexamethylene diisocyanate, toluene diisocyanate. Isocyanate compounds, compounds that can be cross-linked by electrophilic substitution reaction on aromatic rings of lignin derivatives, aldehydes such as formaldehyde, acetaldehyde, paraformaldehyde, furfural, aldehyde sources such as polyoxymethylene, hexamethylenetetramine In addition, a known cross-linking agent such as a resol-type phenol resin or a compound that can be cross-linked by electrophilic substitution reaction with respect to the aromatic ring of a lignin derivative can be used. And it is preferable that the content rate of the said compound in a crosslinking agent is 80 mass% or more before bridge | crosslinking reaction. Moreover, it is preferable that the said compound is 5-60 mass parts with respect to 100 mass parts of lignin derivatives, and it is more preferable that it is 10-50 mass parts.

  Furthermore, examples of the crosslinking agent component other than the above compounds include imidazoles such as 2-methylimidazole and 2-ethyl-4-methylimidazole, 1,8-diazabicyclo (5,4,0) undecene-7, 1 , 5-diazabicyclo (4.3.0) nonane-5-ene anionic polymerization catalyst, triphenylsulfonium hexafluorophosphate, sulfonium salt such as diphenylsulfonium tetrafluoroborate, phenyldiazonium hexafluorophosphate, phenyldiazonium And cationic polymerization catalysts such as diazonium salts such as tetrafluoroborate.

  Moreover, when a reactive functional group is introduced into the lignin derivative as described later, in addition to the above compound, a crosslinking agent component corresponding to the type of the reactive functional group may be appropriately selected and used.

  Specifically, when the reactive functional group is an epoxy group, for example, a phenol resin such as a novolak type phenol resin, a lignin compound having a phenolic hydroxyl group, diethylenetriamine, m-xylylenediamine, N-aminoethylpiperazine For general epoxy resins such as amine compounds, acid anhydrides such as phthalic anhydride, succinic anhydride, maleic anhydride, dicyandiamide, guanidines, 2-methylimidazole, 2-ethyl-4-methylimidazole, etc. A curing agent is mentioned.

  When the reactive functional group is an isocyanate group, examples of the crosslinking agent component include general curing agents for isocyanate resins such as phenol resins, lignin decomposition products, polyvinyl alcohol, and polyamine compounds. One of them or a mixture of two or more of them is used.

  When the reactive functional group is a vinyl group, examples of the crosslinking agent component include an anionic polymerization initiator such as butyl lithium and sodium ethoxide, azobisisobutyronitrile (AIBN), benzoyl peroxide ( A polymerization initiator of a general vinyl group-containing compound such as a radical polymerization initiator such as BPO) may be mentioned, and one or a mixture of two or more of these may be used.

  Further, when the reactive functional group is an ethynyl group, examples of the crosslinking agent component include polymerization catalysts for general ethynyl group-containing compounds such as molybdenum pentachloride, tungsten pentachloride, norbornadiene rhodium chloride dimer, and the like. Among them, one kind or a mixture of two or more kinds is used.

  When the reactive functional group is a maleimide group, examples of the crosslinking agent component include peroxides such as BPO and polymerization initiators of general maleimide group-containing compounds such as the anionic polymerization initiator described above. One or a mixture of two or more of these is used.

  When the reactive functional group is a cyanate group, examples of the crosslinking agent component include a polymerization catalyst of a general cyanate group-containing compound such as a metal catalyst such as cobalt naphthenate. A seed or a mixture of two or more is used.

  Even when these crosslinking agent components are included, the content of the compound in the crosslinking agent is preferably set to 80% by mass or more before the crosslinking reaction.

(Latent catalyst)
Further, in addition to the crosslinking agent, a latent catalyst that varies the presence or absence of the crosslinking reaction or the speed of the crosslinking reaction according to the temperature may be included. By including such a latent catalyst, the lignin resin composition and the lignin resin molding material of the present invention start a crosslinking reaction of the crosslinking agent when heated, or increase the reaction rate of the crosslinking reaction. Will be able to do. As a result, when the molding material is filled in the mold cavity, the crosslinking reaction is not caused or the reaction rate is slowed, and when the molding is completed, the temperature is increased to cause the crosslinking reaction or the reaction. The speed can be increased. As a result, it is possible to fill the cavity with the molding material without gaps, and to obtain a resin molded product that is homogeneous and excellent in mechanical properties, durability, and appearance.

  Examples of the latent catalyst include compounds that release an acidic substance by heating. This acidic substance acts to promote the crosslinking reaction by the crosslinking agent. Thereby, the curing rate when heated is increased, the appearance of the resin molded product is improved, and the production efficiency can be increased.

  Further, the compound that releases an acidic substance by heating is preferably a compound that releases an acidic substance having a dissociation constant pKa of 2 or less by heating. By including a compound capable of releasing such an acidic substance as a latent catalyst, the crosslinking reaction by the crosslinking agent can be particularly accelerated.

  Examples of the acidic substance having a dissociation constant pKa of 2 or less include oxalic acid (pKa = 1.3), p-toluenesulfonic acid (pKa = 1.7), and the like.

  Examples of compounds that release such acidic substances include cyclohexyl = 4-methylbenzenesulfonate, 2-methylcyclohexyl = 4-methylbenzenesulfonate, 3-methylcyclohexyl = 4-methylbenzenesulfonate, and 4-methylcyclohexyl. = 4-methylbenzenesulfonate, 4-butylcyclohexyl = 4-methylbenzenesulfonate, 4-cyclohexylcyclohexyl = 4-methylbenzenesulfonate, 2,6-dimethylcyclohexyl = 4-methylbenzenesulfonate, 2,4-dimethylcyclohexyl = 4 -Methylbenzenesulfonate, 3,4-dimethylcyclohexyl = 4-methylbenzenesulfonate, 3,5-dimethylcyclohexyl = 4-methylbenzenesulfonate, 2-I Propyl-5-methylcyclohexyl = 4-methylbenzenesulfonate, 2-hydroxycyclohexyl = 4-methylbenzenesulfonate, 4-hydroxycyclohexyl = 4-methylbenzenesulfonate, cyclohexyl = 4-biphenylsulfonate and 4,4′-bicyclohexyl = Benzylsulfonic acid cyclohexyls such as bis (4-methylbenzenesulfonate), various aromatic sulfonic acid cyclohexyls such as cyclohexyl = 1-naphthalenesulfonate and naphthalenesulfonic acid cyclohexyls such as cyclohexyl-2-naphthalenesulfonate. It is done. Such cyclohexyl sulfonates are useful as latent catalysts because they release acid substances stably and hardly inhibit the crosslinking reaction by the crosslinking agent.

  Of these, hexyl benzenesulfonate is particularly preferably used, and cyclohexyl = 4-methylbenzenesulfonate, 3-methylcyclohexyl = 4-methylbenzenesulfonate, 3,5-dimethylcyclohexyl = 4-methylbenzenesulfonate. 4-butyl cyclohexyl 4-methylbenzenesulfonate, 2-isopropyl-5-methylcyclohexyl 4-methylbenzenesulfonate, 2-hydroxycyclohexyl 4-methylbenzenesulfonate, and 4-hydroxycyclohexyl 4-methylbenzenesulfonate At least one selected from the group is more preferably used, and cyclohexyl = 4-methylbenzenesulfonate is more preferably used. According to the hexyl benzenesulfonates, the effects brought about by the cyclohexyl aromatic sulfonates become more remarkable.

  Moreover, it is preferable that the heating temperature in which an acidic substance is discharge | released in the compound mentioned above is about 120-150 degreeC. Since such a temperature range is very close to the temperature of the treatment for curing the lignin resin molding material containing the lignin derivative and the crosslinking agent, for example, the lignin resin molding material is molded at a temperature lower than this temperature range, and then this temperature is used. By raising the temperature to the range, excellent moldability and mechanical properties after curing can be made highly compatible.

(Filler)
Examples of fillers include talc, calcined clay, unfired clay, mica, silicates such as glass, oxides such as titanium oxide and alumina, fused silica (fused spherical silica, fused crushed silica), crystalline silica Silicon compounds like, carbonates like calcium carbonate, magnesium carbonate, hydrotalcite, hydroxides like aluminum hydroxide, magnesium hydroxide, calcium hydroxide, like barium sulfate, calcium sulfate, calcium sulfite Sulfate or sulfite, zinc borate, barium metaborate, aluminum borate, calcium borate, borate such as sodium borate, powder such as nitride such as aluminum nitride, boron nitride, silicon nitride, glass In addition to inorganic fillers such as fiber, carbon fiber, etc., wood powder, pulp pulverized powder, cloth砕粉, cured thermosetting resin powder, organic fillers, and the like, such as aramid fibers. Among these, as the filler, among metal oxide, metal hydroxide, metal nitride, silicon oxide, glass fiber, carbon fiber, aramid fiber, wood powder, pulp pulverized powder, and cloth pulverized powder, Those containing at least one kind are preferably used. These fillers can reliably reduce the expansion coefficient of a resin molded product produced from the lignin resin molding material.

  In this case, the content of the filler is preferably 10 to 1000 parts by mass, more preferably 20 to 500 parts by mass, and 100 to 400 parts by mass with respect to 100 parts by mass of the resin material. Is more preferable. When the content rate of a filler is less than the said lower limit, there exists a possibility that the expansion coefficient of the resin molded product manufactured from the lignin resin molding material cannot fully be reduced. On the other hand, if the content of the filler exceeds the upper limit, the proportion of the filler is too large, and the moldability of the lignin resin molding material may be reduced.

  Moreover, it is preferable that the average particle diameter of a filler is about 0.1-500 micrometers, and it is more preferable that it is about 0.2-300 micrometers. When the average particle diameter of the filler is within the above range, the resin molded product produced from the lignin resin molding material is highly compatible with low expansion rate and excellent moldability. The average particle size of the filler refers to the particle size of the powder distributed in 50% of the cumulative volume in the particle size distribution of the filler.

  In addition, examples of the shape of the filler include, but are not particularly limited to, flake shape, dendritic shape, spherical shape, and fibrous shape.

  In addition, when a filler is fibrous, it is preferable that it is a fiber diameter of 0.5-100 micrometers and fiber length about 1-50 mm.

(Other ingredients)
In addition, the lignin resin molding material of this invention may contain other resin components other than a lignin derivative and a crosslinking agent. Specific examples include an epoxy resin, a phenol resin, a furan resin, a urea resin, and a melamine resin. By including these resin components, the relative melt viscosity of the resin components is lowered, so that the moldability of the lignin resin molding material is improved. When these resin components are included, the content of the lignin derivative is preferably adjusted to 50% by mass or more, more preferably 60% by mass or more before the crosslinking reaction.

In addition to the above components, the lignin resin molding material of the present invention includes, as necessary, an alkali metal salt such as sodium methoxy, t-butoxy potassium, an alkaline earth metal salt such as calcium acetate, Na ₂ O, K _A hardening accelerator such as an alkali metal oxide such as ₂ O and an alkaline earth metal oxide such as CaO or BaO may be included.

  In particular, when a lignin secondary derivative having an epoxy group as a reactive group is included, for example, imidazoles such as 2-methylimidazole and 2-ethyl-4-methylimidazole, 1,8-diazabicyclo (5, 4,0) undecene-7,1,5-diazabicyclo (4.3.0) nonane-5-ene, tris (dimethylaminomethyl) phenol, tertiary amines such as benzyldimethylamine, triphenylphosphine, tetra -N-butylphosphonium tetraphenylborate or the like may be contained.

Moreover, when the lignin secondary derivative which has a methylol group, a vinyl group, an ethynyl group, a maleimide group, a cyanate group etc. as a reactive group is included, the said polymerization catalyst may be included, for example.
Furthermore, various additives may be included as necessary.

  Examples of such additives include silane coupling agents such as epoxy silane, mercapto silane, amino silane, alkyl silane, ureido silane, and vinyl silane, titanate coupling agents, aluminum coupling agents, and aluminum / zirconium coupling agents. Various coupling agents, colorants such as carbon black, bengara, polyethylene wax, higher fatty acid esters, fatty acid amides, ketones and amines, synthetic waxes such as hydrogenated oils, natural waxes such as paraffin wax and montan wax, Higher fatty acids such as stearic acid and zinc stearate and metal salts thereof, mold release agents such as paraffin, silicone oil, low stress components such as silicone rubber, antimony trioxide, aluminum hydroxide, Examples include magnesium oxide, zinc borate, zinc molybdate, a flame retardant such as phosphazene, an inorganic ion exchanger such as bismuth oxide hydrate, an internal mold release agent, and the like. A combination is used.

  Moreover, when a lignin resin molding material contains a mold release agent, it is preferable that content of a mold release agent is 0.01-10 mass parts with respect to 100 mass parts of lignin derivatives, and 0.1-5 mass parts It is more preferable that In addition, when the content of the release agent is less than the above, when the lignin resin molding material is filled in a mold and molded, the mold release property may be insufficient, whereas the content of the release agent When the value exceeds the upper limit, the curability of the lignin resin molding material may be lowered.

  The lignin resin molding material of the present invention may be in the form of liquid, powder or the like, but is preferably in the form of tablets or granules. Thereby, the shaping | molding stability of a lignin resin molding material can be improved more.

Examples of the tablet shape include a cylinder, a cone, and a truncated cone.
On the other hand, the average particle size of the granules is preferably about 10 to 6000 μm, and more preferably about 100 to 5000 μm.

<Method for producing lignin molding material>
Next, a method for producing the lignin resin molding material of the present invention will be described.

  The method for producing the lignin resin molding material of the present invention comprises: [1] a step of placing biomass in the presence of a solvent and decomposing them under high temperature and high pressure, and [2] treating a solid component in the treated product with a polar solvent. A step of separating the insoluble matter from the polar solvent and the solution, [3] drying the solution and recovering the solute (lignin derivative), and [4] mixing the recovered solute and crosslinking agent. And a step of obtaining a lignin resin molding material. Hereinafter, each process will be described sequentially.

[1]
First, biomass is placed in the presence of a solvent and decomposed under high temperature and pressure. Biomass is a plant or a processed product of a plant as described above. Examples of this plant include broadleaf trees such as beech, birch and oak, conifers such as cedar, pine and cypress, bamboo, rice straw. Such grasses, coconut shells and the like.

  In the decomposition treatment, it is preferable to pulverize the biomass into blocks, chips, powders, or the like. In that case, the size after pulverization is preferably about 100 μm to 1 cm, and more preferably about 200 to 1000 μm. By using biomass of such a size, it is possible to improve the dispersibility of the biomass in the liquid and to efficiently perform the biomass decomposition treatment.

  Examples of the solvent used in this step include water, alcohols such as methanol and ethanol, phenols such as phenol and cresol, ketones such as acetone and methyl ethyl ketone, dimethyl ether, ethyl methyl ether, diethyl ether, Ethers such as tetrahydrofuran, nitriles such as acetonitrile, amides such as N, N-dimethylformamide, and the like, and one or two or more of them are used as a mixed solvent.

  As the solvent, water is particularly preferably used. As the water, for example, ultrapure water, pure water, distilled water, ion exchange water or the like is used. By using water, unintended denaturation of the lignin derivative is suppressed, and the waste liquid generated with the decomposition treatment is aqueous, so the environmental burden can be minimized. As a usage-amount of a solvent, it is so good that it is large with respect to biomass, However, Preferably it is about 1-20 mass times with respect to biomass, and it is more preferable that it is about 2-10 mass times.

  Next, the biomass in the presence of the solvent is decomposed under high temperature and pressure. Thereby, biomass is decomposed | disassembled into lignin, a cellulose, hemicellulose, those other decomposition products, reaction materials, etc.

  In the generation of a high temperature and high pressure environment, a pressure vessel such as an autoclave is used. Moreover, as this pressure vessel, what is equipped with a heating means and a stirring means is used preferably, and it is preferable to stir biomass under high temperature and pressure. Moreover, you may provide the means to pressurize independently from the factor which influences pressure, such as the temperature in a container, as needed. Examples of such means include means for introducing an inert gas such as argon gas into the container.

  As for the conditions in the decomposition treatment, the treatment temperature is preferably 150 to 400 ° C, more preferably 180 to 350 ° C, and further preferably 220 to 320 ° C. When the treatment temperature is within the above range, the molecular weight of the lignin derivative obtained after decomposition can be optimized. Thereby, the moldability of the lignin resin molding material and the mechanical properties after curing can be made compatible with the hardness.

  Moreover, it is preferable that the processing time in a decomposition process is 480 minutes or less, and it is more preferable that it is 30 to 360 minutes. If the treatment time is within the above range, the ratio of the aromatic proton and the aliphatic proton of the lignin derivative obtained after decomposition becomes an appropriate value, and the moldability of the lignin resin molding material and the mechanical properties after curing are obtained. Highly compatible.

  Furthermore, the pressure in the decomposition treatment is preferably 1 to 40 MPa, more preferably 1.5 to 25 MPa, and further preferably 3 to 20 MPa. When the pressure is within the above range, the biomass decomposition efficiency can be significantly increased, and the processing time can be shortened accordingly.

  In addition, it is preferable to perform the process which fully stirs biomass and the said solvent as a pre-process of a decomposition | disassembly process, and adjusts both. Thereby, the decomposition of biomass can be particularly optimized. The stirring temperature is preferably about 0 to 150 ° C, and more preferably about 10 to 130 ° C. Further, the stirring time is preferably about 1 to 120 minutes, more preferably about 5 to 60 minutes. Further, examples of the stirring method include various mills such as a ball mill and a bead mill, a method using a stirrer equipped with a stirring blade, a method using water flow stirring using a homogenizer, a jet pump, and the like.

  Moreover, you may make it add the catalyst and oxidizing agent which accelerate | stimulate a decomposition process as needed in a solvent. Examples of the catalyst include inorganic bases such as sodium carbonate, inorganic acids such as acetic acid and formic acid, and examples of the oxidizing agent include hydrogen peroxide. The amount of the catalyst and the oxidizing agent added is preferably about 0.1 to 10% by mass, more preferably about 0.5 to 5% by mass in terms of the concentration in the aqueous solvent.

  Further, as a pretreatment for the decomposition treatment, it is preferable to perform a step of sufficiently stirring the biomass and the aqueous solvent and allowing them to blend. Thereby, the decomposition of biomass can be particularly optimized.

  In addition, as stirring temperature, it is preferable that it is about 0-150 degreeC, and it is more preferable that it is about 10-130 degreeC.

  Moreover, as stirring time, it is preferable that it is about 1 to 120 minutes, and it is more preferable that it is about 5 to 60 minutes.

  Further, examples of the stirring method include various mills such as a ball mill and a bead mill, a method using a stirrer equipped with a stirring blade, a method using water flow stirring using a homogenizer, a jet pump, and the like.

The solvent used in the decomposition treatment is preferably used in a subcritical or supercritical state (condition). A solvent in a subcritical or supercritical state can accelerate the biomass decomposition treatment without a special additive component such as a catalyst. For this reason, it becomes possible to decompose biomass in a short time without using a complicated separation process, and it is possible to reduce the manufacturing cost of the lignin derivative and simplify the manufacturing process.
As an example, the critical temperature of water is about 374 ° C., and the critical pressure is about 22.1 MPa.

[2]
Next, the processed product in the pressure vessel is filtered. Then, the filtrate is removed, and the solid component separated by filtration is recovered. And the collect | recovered solid component is immersed in the solvent in which lignin is soluble. The solid component immersed in a solvent capable of lignin is separated into a component soluble in the solvent (soluble component) and a component insoluble in the solvent (insoluble component).

  As the solvent in which lignin is soluble, various polar solvents are used, and particularly those containing lower alcohols such as methanol and ethanol, and ketones such as acetone and methyl ethyl ketone are preferably used. By using these polar solvents, it is possible to separate and extract the lignin derivative dissolved in the polar solvent and the lignin derivative insoluble in the polar solvent from the recovered solid component.

  The immersion time is not particularly limited, but is preferably about 1 to 48 hours, and more preferably about 2 to 30 hours. Moreover, it is also possible to heat at the boiling point or less of a solvent at the time of immersion.

[3]
Next, the processed product obtained by the dipping process is filtered. Then, the solvent in which lignin is soluble is distilled off from the filtrate (dissolved solution), and the dried solute (lignin derivative) is recovered.
On the other hand, insolubles are also recovered from the treated product by filtration.

  When obtaining a lignin resin molding material containing a lignin secondary derivative, a reactive functional group is introduced into the lignin derivative by contacting the extracted lignin derivative with a compound containing a reactive functional group. It may be.

  As a method for introducing a reactive functional group, for example, a method of mixing a lignin derivative and a compound containing a reactive functional group is used, and after mixing, a catalyst or the like may be added as necessary.

  Specifically, when introducing an epoxy group, a lignin derivative, epichlorohydrin, and a solvent are mixed, and a base catalyst such as sodium hydroxide may be added thereto under reflux under reduced pressure.

  In addition, when introducing a vinyl group, a lignin derivative, a halogen compound containing a vinyl group such as an allyl halide or a vinylbenzyl halide, and a solvent are mixed, and a base catalyst such as sodium hydroxide is added to the mixture under heating and stirring. do it.

  In addition, when introducing an ethynyl group, a lignin derivative, a halogen compound containing an ethynyl group such as a propargyl halide or a phenylacetylene halide, and a solvent are mixed, and a base catalyst such as sodium hydroxide is added to the mixture with heating and stirring. do it.

  Moreover, when introduce | transducing a cyanate group, a lignin derivative, halogenated cyanate, and a solvent are mixed, and a base catalyst, such as sodium hydroxide, may be added to this under heating and stirring.

  When introducing a maleimide group, a lignin derivative and parachloronitrobenzene are mixed. As a result, a chloro group reacts with the phenolic hydroxyl group of the lignin derivative to obtain a polynitrated lignin bonded via an ether bond. Subsequently, polynitrated lignin is reduced to be converted to polyaminated lignin, and further reacted with maleic anhydride to introduce a maleimide group.

  Moreover, when introduce | transducing an isocyanate group, the hydroxyl group in a lignin derivative is converted into a carboxyl group by mixing a lignin derivative and maleic anhydride. Thereafter, the isocyanate group is introduced by heating the mixture in the presence of diphenyl phosphate azide.

[4]
Next, the collected solute (lignin derivative), the crosslinking agent, and a filler and other components added as necessary are mixed. Thereby, a lignin resin molding material is prepared.

  Moreover, when mixing, using a kneading machine such as a hot plate, a pressure kneader, a roll, a kneader, or a twin screw extruder, the mixture is heated and melt-kneaded at a temperature lower than the temperature at which the mixture is cured. Although the specific heating temperature at the time of heating is a little different depending on the composition to be selected, it is preferably about 50 to 130 ° C. By pulverizing the cooled mixture, a granular lignin resin molding material can be obtained.

  Moreover, when preparing a lignin resin molding material, you may make it add an organic solvent as needed. Examples of the organic solvent include, but are not limited to, methanol, ethanol, propanol, butanol, methyl cellosolve, acetone, methyl cellosolve, methyl ethyl ketone, methyl isobutyl ketone, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, quinoline, cyclopentanone, xylene, m-cresol, chloroform and the like can be mentioned, and one or a mixture of two or more of these can be used.

In addition, you may make it add a diluent as needed. Examples of the diluent include organic solvents having a relatively high boiling point such as butyl cellosolve, carbitol, butyl cellosolve acetate, carbitol acetate, ethylene glycol diethyl ether, and α-terpineol.
Furthermore, other additives may be included.

  Examples of such additives include silane coupling agents such as epoxy silane, mercapto silane, amino silane, alkyl silane, ureido silane, and vinyl silane, titanate coupling agents, aluminum coupling agents, and aluminum / zirconium coupling agents. Various coupling agents, colorants such as carbon black, bengara, polyethylene wax, higher fatty acid esters, fatty acid amides, ketones / amines, synthetic waxes such as hydrogenated oil, paraffin wax, montan wax, stearic acid, etc. Natural waxes, higher fatty acids such as stearic acid and zinc stearate and their metal salts, release agents such as paraffin, silicone oil, low stress components such as silicone rubber, antimony trioxide, hydroxylation Examples thereof include flame retardants such as luminium, magnesium hydroxide, zinc borate, zinc molybdate, phosphazene, inorganic ion exchangers such as bismuth oxide hydrate, and one or more of these are combined. Things are used.

<Lignin resin molded product>
Next, the lignin resin molded product manufactured from the lignin resin molding material of this invention is demonstrated. The lignin resin molded product is produced by molding the lignin resin molding material of the present invention and then curing it.

  Specifically, the lignin resin molding material is manufactured by heating and pressing in a molding die and then curing.

  The temperature at the time of heat and pressure molding is preferably about 100 to 280 ° C, more preferably about 120 to 250 ° C. Further, the pressure is preferably about 0.5 to 20 MPa, more preferably about 1 to 10 MPa.

  The obtained lignin resin molded product is applied to uses such as semiconductor parts, aircraft parts, automobile parts, industrial machine parts, electronic parts, electrical parts, mechanical parts, and the like.

  The molding method is not particularly limited, and the lignin resin molding material of the present invention is formed into a molded product using a known molding method, for example, an injection molding method, a compression molding method, an extrusion molding method, a cast molding method, or the like. Can do. The form of the molded product thus obtained may be any form, for example, an intermediate molded product before the molding material is made into a final molded product or a final molded product. .

  In the lignin resin molding material, the lignin derivative is cross-linked with a cross-linking agent and cured by heating. However, the cross-linking reaction point between the cross-linking agent and the lignin derivative is caused by a condensation reaction accompanying a dealcoholization reaction or a dehydration reaction. It is thought to crosslink.

  Further, when the lignin derivative is methylolated, a dehydration condensation reaction occurs, the crosslinking agent and the methylol group are crosslinked, and the crosslinking agent and the lignin derivative are self-condensed.

  Due to the reaction described above, when the lignin resin composition and the lignin resin molding material are cured, the generation of volatile components accompanying the reaction is gentle, so that problems such as swelling and voids can be effectively suppressed.

  Although the present invention has been described above, the present invention is not limited to this. For example, an optional component may be added to the lignin resin composition and the lignin resin molding material.

  Further, by impregnating a core material such as paper or fabric with the lignin resin composition, a resin plate having excellent mechanical properties, durability and appearance can be produced. As the core material, for example, thin paper, craft paper, titanium paper, linter paper, paperboard, base paper for gypsum board, coated paper, art paper, sulfuric acid paper, glassine paper, parchment paper, paraffin paper, Japanese paper and various other papers, glass Fiber, asbestos fiber, potassium titanate fiber, alumina fiber, silica fiber, carbon fiber, metal fiber, inorganic fiber such as mineral fiber, synthetic resin fiber such as aramid fiber, polyester fiber, acrylic fiber, vinylon fiber or natural fiber Non-woven fabrics or woven fabrics of various fibers such as these are used, and one or more of these composites are used.

Next, specific examples of the present invention will be described.
1. Manufacturing of lignin resin molding materials and lignin resin moldings

Example 1
(1) Extraction of lignin derivative 100 g of cedar wood flour (60 mesh under) and 400 g of a solvent made of pure water were mixed and introduced into a 1 L autoclave. Then, while stirring the contents at 300 rpm, as a pretreatment, the mixture was stirred for 15 minutes at room temperature. After sufficiently blending the cedar wood flour and the solvent, it was treated at 300 ° C. and 10 MPa for 60 minutes to obtain cedar wood flour. Disassembled.

Subsequently, the obtained decomposition product was filtered, and the solid component separated by filtration was recovered.
Subsequently, the obtained solid component was immersed in acetone which is a polar solvent, and separated into an insoluble component and a soluble component with respect to acetone. This was filtered, and the solution separated by filtration was recovered.
Next, the solution was dried to recover the solute (lignin derivative).

(2) Preparation of lignin resin molding material Next, 100 parts by mass of the obtained lignin derivative, 30 parts by mass of hexamethoxymethylmelamine (first grade reagent manufactured by Tokyo Chemical Industry Co., Ltd.), silica powder (manufactured by Denki Kagaku, average particle size) 200 parts by mass), and kneaded with a hot roll at 90 ° C. for 5 minutes to obtain a sheet-like kneaded product. Hexamethoxymethylmelamine is a crosslinking agent component and is a compound represented by the above formula (7) (where n = 1).

  Next, the sheet-like kneaded product was cooled and then pulverized to obtain a granular lignin resin molding material having an average particle diameter of 3 mm.

(3) Production of Lignin Resin Molded Product Next, the obtained granular lignin resin molding material was supplied to a tablet machine to obtain a tablet having an outer diameter of 20 mm.

  Subsequently, it shape | molded by transfer molding on 175 degreeC and the molding conditions of 6.9 MPa for 5 minutes, and obtained the plate-shaped lignin resin molded product of average thickness 1.6mm.

(Examples 2 to 13)
A lignin resin molded product was obtained in the same manner as in Example 1 except that the type of biomass, the extraction conditions of the lignin derivative, and the preparation conditions of the lignin resin molding material were changed as shown in Table 1.

(Example 14)
A lignin resin molded product was obtained in the same manner as in Example 1 except that the crosslinking agent component was changed to hexamethylol melamine pentamethyl ether. In addition, hexamethylol melamine pentamethyl ether is a compound (however, n = 1) represented by the said Formula (6).

(Example 15)
A lignin resin molded product was obtained in the same manner as in Example 1 except that the cross-linking agent component was changed to pentamethoxymethyl melamine (MX-750LM manufactured by Sanwa Chemical Co., Ltd.). Pentamethoxymethylmelamine is a compound represented by the following formula (11).

(Example 16)
A lignin resin was formed in the same manner as in Example 1 except that 2 parts by mass of cyclohexyl = 4-methylbenzenesulfonate was added to the lignin resin molding material as a compound that releases p-toluenesulfonic acid (pKa = 1.7) by heating. A molded product was obtained. The acid release temperature of cyclohexyl = 4-methylbenzenesulfonate is 138 ° C.

(Example 17)
Except that 2 parts by mass of 4-butylcyclohexyl-4-methylbenzenesulfonate was added to the lignin resin molding material as a compound that releases p-toluenesulfonic acid (pKa = 1.7) by heating, the same as in Example 1. Thus, a lignin resin molded product was obtained. The acid release temperature of 4-butylcyclohexyl = 4-methylbenzenesulfonate is 144 ° C.

(Example 18)
The extracted lignin derivative was contacted with formaldehyde in an aqueous alkaline solution to form methylol. A lignin resin molded product was obtained in the same manner as in Example 1 except that a lignin resin molding material was prepared using this methylolated lignin derivative.

(Example 19)
A lignin resin molded product was obtained in the same manner as in Example 1 except that the liquid epoxy resin was added to the lignin resin molding material. The amount of epoxy resin added was such that the ratio (mass ratio) of lignin resin / epoxy resin was 70/30. In addition to 21 parts by mass of the compound represented by the above formula (7) as a crosslinking agent, triphenylphosphine was added. The amount of triphenylphosphine added was 1 part by mass with respect to 100 parts by mass of the resin material. In addition, Adeka Sizer O-180A manufactured by ADEKA was used as the liquid epoxy resin.

(Example 20)
A lignin resin molded product was obtained in the same manner as in Example 1 except that the liquid furan resin was added to the lignin resin molding material. The amount of furan resin added was such that the ratio (mass ratio) of lignin resin / furan resin was 70/30. Further, FR-16475 manufactured by Sumitomo Bakelite Co., Ltd. was used as the liquid furan resin.

(Examples 21 and 22)
The type of biomass was changed as shown in Table 2, and a lignin resin molded product was obtained in the same manner as in Example 1 except that the decomposition of biomass and the extraction process of the lignin derivative were changed as follows.

First, 50 g of biomass powder was placed in a 2 L beaker, a methanol solution of p-cresol was added, stirred with a glass rod, and allowed to stand for 24 hours. Thereafter, methanol was completely distilled off to obtain p-cresol sorption wood flour. To this wood flour, 500 ml of 72 mass% sulfuric acid was added and stirred vigorously at 30 ° C. for 1 hour, and then the mixture was poured into a large excess of water to recover insoluble matter.
Next, the recovered insoluble matter was deacidified and dried to obtain a lignin derivative.

(Example 23)
(1) Extraction of lignin derivative A lignin derivative was extracted in the same manner as in Example 1.

(2) Preparation of lignin resin molding material Next, the extracted lignin derivative and epichlorohydrin were introduced into a three-necked flask equipped with a stirrer and a cooling tube, and 100 mmHg (1.3 × 10 ⁴ Pa) was introduced. While refluxing under reduced pressure, 2 g of a 20% strength by weight aqueous sodium hydroxide solution was added dropwise over 30 minutes. Thereafter, the reaction mixture was obtained by maintaining the reduced-pressure reflux state for 90 minutes.

  Next, the insoluble matter was removed from the reaction product by filtration, and the epichlorohydrin soluble portion was isolated. And epichlorohydrin was distilled off from this epichlorohydrin soluble part, and the lignin secondary derivative in which the epoxy group was introduce | transduced was obtained by making it dry.

  Thereafter, a lignin resin molding material was obtained in the same manner as in Example 1 except that the obtained lignin secondary derivative was used and the content of the silica powder was changed as shown in Table 3.

(3) Production of lignin resin molded article Next, a lignin resin molded article was obtained in the same manner as in Example 1.

(Example 24)
A lignin derivative was extracted in the same manner as in Example 4, and allylpromide was used instead of epichlorohydrin to obtain a lignin secondary derivative into which a vinyl group was introduced, and this was used to form a lignin resin molding material. A lignin resin molded product was obtained in the same manner as in Example 23 except that the above was prepared. The content of silica powder was changed as shown in Table 3.

(Example 25)
A lignin resin molded product was obtained in the same manner as in Example 23 except that the lignin derivative was extracted and used in the same manner as in Example 8 and the preparation conditions of the lignin resin molding material were changed as shown in Table 3. It was.

(Example 26)
The lignin was prepared in the same manner as in Example 1 except that the crosslinker component was changed to Nicalac MX-290 (manufactured by Sanwa Chemical Co., Ltd., equivalent to the compound represented by the above formula (3) in which R is CH ₃ ). A resin molded product was obtained.

(Example 27)
The lignin was treated in the same manner as in Example 1 except that the crosslinker component was changed to Nicalac MX-280 (manufactured by Sanwa Chemical Co., equivalent to the compound represented by the above formula (4) in which R is CH ₃ ). A resin molded product was obtained.

(Example 28)
The lignin was treated in the same manner as in Example 1 except that the crosslinker component was changed to Nicalac MX-270 (manufactured by Sanwa Chemical Co., equivalent to the compound represented by the above formula (5) in which R is CH ₃ ). A resin molded product was obtained.

(Example 29)
A lignin resin molded product was obtained in the same manner as in Example 1 except that the crosslinking agent component was changed to the compound represented by the following formula (12).

(Example 30)
A lignin resin molded product was obtained in the same manner as in Example 1 except that the crosslinking agent component was changed to the compound represented by the following formula (13).

(Example 31)
A lignin resin molded product was obtained in the same manner as in Example 1 except that the crosslinking agent component was changed to quinuclidine.

(Example 32)
A lignin resin molded product was obtained in the same manner as in Example 1 except that the crosslinking agent component was changed to pidgin.

(Comparative Example 1)
A phenol resin molded product was obtained in the same manner as in Example 1 except that the phenol resin molding material prepared as follows was used.

  100 parts by mass of a commercially available novolac type phenol resin (PR-53195, manufactured by Sumitomo Bakelite Co., Ltd.), 10 parts by mass of hexamethylenetetramine, and 200 parts by mass of silica powder (manufactured by Denki Kagaku Co., Ltd., average particle size: 15 μm), A sheet-like kneaded product was obtained by kneading with a roll at 90 ° C. for 5 minutes.

  Next, after the sheet-like kneaded product was cooled, it was pulverized to obtain a granular phenol resin molding material having an average particle diameter of 3 mm.

(Comparative Example 2)
A lignin resin molded product was obtained in the same manner as in Example 1 except that the crosslinking agent component was changed to hexamethylenetetramine. In addition, hexamethylenetetramine was added at a ratio of 10 parts by mass with respect to 100 parts by mass of the lignin derivative.

(Comparative Example 3)
A lignin resin molded product was obtained in the same manner as in Example 6 except that the crosslinking agent component was changed to hexamethylenetetramine. In addition, hexamethylenetetramine was added at a ratio of 10 parts by mass with respect to 100 parts by mass of the lignin derivative.

  The production conditions of the lignin resin molded product in each Example and each Comparative Example are shown in Tables 1, 2, and 4. Abbreviations in Tables 1, 2, and 4 correspond to the compounds shown below.

HMMM: Hexamethoxymethyl melamine HMMPME: Hexamethylol melamine pentamethyl ether PMMM: Pentamethoxymethyl melamine HMTA: Hexamethylenetetramine CH4MBS: Cyclohexyl = 4-methylbenzenesulfonate 4BC4MBS: 4-butylcyclohexyl = 4-methylbenzenesulfonate MX-290: Nikarak MX-290
MX-280: Nikarak MX-280
MX-270: Nikarak MX-270

2. Evaluation of lignin derivative 2.1 Evaluation of gel time 10 g of hexamethoxymethyl melamine (first grade reagent manufactured by Tokyo Chemical Industry Co., Ltd.) was added to 90 g of the lignin derivative obtained in each Example and each Comparative Example. The gel time (gelation time) at 150 ° C. was measured according to the method specified in JIS K 6910. The measurement results are shown in Tables 1 and 2.

  As is clear from Tables 1 and 2, the lignin derivative used in each example has a gel time value that is not too low and not too high (preferably about 30 to 190). A lignin resin molding material containing a derivative has high moldability and excellent mechanical properties after curing.

2.2 Evaluation by NMR analysis For the lignin derivatives obtained in each Example and each Comparative Example, spectra of chemical shifts by ¹ H-NMR analysis were obtained, and the fragrance relative to the integrated value of a plurality of peaks attributed to aliphatic protons was obtained. The ratio of integral values of a plurality of peaks belonging to group protons was calculated, and the calculation results are shown in Tables 1 and 2.

2.3 Evaluation of Number Average Molecular Weight The number average molecular weight (Mn) was measured for the lignin derivatives obtained in each Example and each Comparative Example, and the measurement results are shown in Tables 1 and 2.

3. Evaluation of Lignin Resin Molding Material and Lignin Resin Composition 3.1 Evaluation of Spiral Flow Spiral flow was measured for the lignin resin molding material obtained in each Example and each Comparative Example. For the measurement, a spiral flow measurement mold was used, and the spiral flow was measured according to the method prescribed in EMMI-1-66 under the conditions of a temperature of 175 ° C., an injection pressure of 6.9 MPa, and a holding time of 300 seconds using a low-pressure transfer molding machine. (SF) value (unit: cm) was measured. And the measured spiral flow value was evaluated according to the following evaluation criteria.

<Evaluation criteria for liquidity>
◯: Spiral flow value is 70 cm or more ×: Spiral flow value is less than 70 cm

3.2 Evaluation of Melt Viscosity Resin varnish (lignin resin composition) having a solid content concentration of 40% dissolved in methanol using a resin formulation excluding the filler from the molding material formulation of each example and each comparative example. Obtained. And this resin varnish was desolvated under reduced pressure at 50 degreeC, the solid content of the resin composition was isolated, and the melt viscosity in 150 degreeC of the obtained solid content was measured. And it evaluated according to the evaluation criteria shown below.

<Evaluation criteria for melt viscosity>
◎: Minimum melt viscosity is less than 3 Pa · s ◎: Minimum melt viscosity is 3 Pa · s or more and less than 5 Pa · s ○: Minimum melt viscosity is 5 Pa · s or more and less than 15 Pa · s △: Minimum melt viscosity Is 15 Pa · s or more and less than 30 Pa · s ×: The minimum melt viscosity is 30 Pa · s or more

  In addition, the Ares viscoelasticity measuring apparatus (made by TA Instruments Japan) was used for the measurement of the melt viscosity of the resin varnish. Moreover, a φ20 mm parallel plate was used as a jig, and the gap was set to 1 mm. And it measured by changing distortion at 1 Hz in 150 degreeC, and measuring distortion dependence.

4). 4. Evaluation of Lignin Resin Molded Product 4.1 Evaluation of Bending Fracture Elongation The lignin resin molded product obtained in each Example and each Comparative Example was subjected to a bending test until breaking according to the method specified in JIS-C6481. went. And the ratio (elongation at the time of bending fracture) of the change of the dimension after a test with respect to the dimension before a test was evaluated according to the following evaluation criteria.

<Evaluation criteria for elongation at bending fracture>
◯: Elongation at bending fracture is 1% or more ×: Elongation at bending fracture is less than 1%

4.2 Evaluation of Appearance The lignin resin molded products obtained in each Example and each Comparative Example were visually checked for appearance and evaluated according to the following evaluation criteria.

<Evaluation criteria for appearance>
A: The surface of the molded product is smooth and no distortion, wrinkles, or spots are observed. ○: The surface of the molded product has irregularities that cannot be seen with the naked eye, or there are 1 to 2 strains, wrinkles, or spots. : Concavities and convexities that can be recognized with the naked eye are observed on the surface of the molded product, or 3 to 5 strains, wrinkles, and spots are observed. The number of spots is 6 or more. The evaluation results of 3 and 4 are shown in Tables 1 to 4.

  As is clear from Tables 1 to 4, it was confirmed that the lignin resin molding material obtained in each example had high fluidity and therefore excellent moldability. And the external appearance of the molded article manufactured with this molding material was favorable. Moreover, the external appearance of the lignin resin molded product obtained in each Example was also favorable. In addition, although the phenol resin molding material obtained by the comparative example 1 does not contain a plant-derived component, it was the same as that of each Example about this molding material and a molded article.

  On the other hand, it was confirmed that the lignin resin molding materials obtained in Comparative Examples 2 and 3 have low fluidity, and thus low moldability. And, the appearance of the molded product produced with this molding material showed somewhat large irregularities and many strains, wrinkles, spots, etc., which are considered to be due to the low moldability of the molding material. It is done. In addition, the lignin resin molded products obtained in Comparative Examples 2 and 3 tend to be brittle, and it was recognized that they hardly stretched at break.

  From the above, according to the present invention, it is possible to obtain a lignin resin composition excellent in fluidity and mechanical properties after curing, and a lignin resin molding material excellent in moldability and mechanical properties after curing. Became clear.

Claims (14)

A lignin resin composition comprising a lignin derivative obtained by decomposing biomass and a crosslinking agent containing a compound represented by the following formula (1).
_{Z- (CH 2 OR) m (} 1)
[Z in Formula (1) is any one of a melamine residue, a urea residue, a glycolyl residue, an imidazolidinone residue, and an aromatic ring residue. Moreover, m represents the integer of 2-14. R is independently an alkyl group having 1 to 4 carbon atoms or a hydrogen atom. However, -CH 2 _OR, the nitrogen atom of the melamine residues, the nitrogen atom of the primary amino groups of the urea residues, the nitrogen atom of the secondary amino group of the glycolyl residues, the secondary amino group of the imidazolidinone residues It is directly bonded to either the nitrogen atom or the carbon atom of the aromatic ring residue. ] The lignin resin composition according to claim 1, wherein the compound is represented by any one of the following formulas (2) to (5).

[In the formula (2), X is _CH 2 OR or a hydrogen atom, R is independently an alkyl group or a hydrogen atom having 1 to 4 carbon atoms. N represents an integer of 1 to 3. ]

[In Formula (3), R is a C1-C4 alkyl group or a hydrogen atom independently. ]

[In Formula (4), R is a C1-C4 alkyl group or a hydrogen atom independently. ]

[In Formula (5), R is a C1-C4 alkyl group or a hydrogen atom independently. ] The lignin resin composition according to claim 2, wherein the compound is a compound represented by the following formula (6) or (7).

[In Formula (6), n represents the integer of 1-3. ]

[In formula (7), n represents the integer of 1-3. ]   A lignin resin composition comprising a lignin derivative obtained by decomposing biomass and a crosslinking agent containing at least one of quinuclidine and pyridine.   The lignin resin composition according to any one of claims 1 to 4, wherein the lignin derivative is obtained by decomposing biomass under subcritical water.   The lignin resin composition according to claim 5, wherein the lignin derivative is a product obtained by further demethylating biomass obtained by decomposing biomass under subcritical water.   The lignin resin composition according to any one of claims 1 to 6, further comprising a latent catalyst that varies the presence or absence of the crosslinking reaction or the speed of the crosslinking reaction depending on the temperature.   The lignin resin composition according to any one of claims 1 to 7, further comprising a compound that releases an acidic substance by heating.   The lignin resin composition according to claim 8, wherein the compound that releases an acidic substance is a compound that releases an acidic substance having a dissociation constant pKa of 2 or less by heating.   The lignin resin composition according to claim 9, wherein the compound that releases an acidic substance is a compound that releases an acidic substance having a dissociation constant pKa of 2 or less by heating at 120 to 150 ° C.   The lignin resin composition according to any one of claims 8 to 10, wherein the compound that releases an acidic substance is cyclohexyl aromatic sulfonate.   The lignin resin composition according to claim 11, wherein the cyclohexyl sulfonates are cyclohexyl benzenesulfonates.   The benzene sulfonates are cyclohexyl = 4-methylbenzene sulfonate, 3-methylcyclohexyl = 4-methylbenzene sulfonate, 3,5-dimethylcyclohexyl = 4-methylbenzene sulfonate, 4-butylcyclohexyl = 4-methylbenzene sulfonate. 2-isopropyl-5-methylcyclohexyl = 4-methylbenzenesulfonate, 2-hydroxycyclohexyl = 4-methylbenzenesulfonate and 4-hydroxycyclohexyl = 4-methylbenzenesulfonate are at least one selected from the group consisting of Item 13. A lignin resin composition according to Item 12.   A lignin resin molding material comprising the lignin resin composition according to any one of claims 1 to 13 and a filler.