JP2016169382A - LIGNIN-CONSTITUTING PHENYL PROPANE UNIT α POSITION CHEMICALLY MODIFIED LIGNOCELLULOSE DERIVATIVE, FIBER OR FIBER ASSEMBLY COMPRISING THE SAME, AND COMPOSITION OR FORMED PRODUCT CONTAINING THE SAME - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a chemically modified lignocellulose derivative (α position modified lignocellulose derivatives, lignocellulose with double modifications) that is light weight, has a high strength, has a low linear thermal expansion coefficient, as well as that can exhibit thermoplasticity; a fiber or fiber assembly comprising chemically modified lignocellulose derivative; and a composition as well as a formed product comprising the same.SOLUTION: Provided is a lignocellulose derivative in which α position of a phenyl propane unit constituting lignin is modified with at least one characteristic group selected from the group consisting of an acyloxy group, an oxy group, and a thio group.SELECTED DRAWING: None

Description

  The present invention comprises a lignocellulose derivative in which the α-position of the phenylpropane unit constituting the lignin in lignocellulose is chemically modified (hereinafter also referred to as “α-modified lignocellulose derivative”), an α-modified lignocellulose derivative. Lignocellulose derivative (hereinafter also referred to as “lignocellulose double-modified product”) in which the hydroxyl group present in at least one of hemicellulose or cellulose (hereinafter also referred to as “sugar chain hydroxyl group of α-modified lignocellulose derivative”) is further chemically modified , Fibers or fiber aggregates containing the same, compositions containing them, and molded bodies.

Lignocellulose is a complex hydrocarbon polymer (natural polymer mixture) that constitutes the cell wall of plants, and is known to be composed mainly of polysaccharide cellulose, hemicellulose, and lignin, which is an aromatic polymer. Reference Example 1: Review Article Conversion of Lignocellulosic Biomass to Nanocellulose: Structure and Chemical Process HV Lee, SBA Hamid, and SK Zain, Scientific World Journal Volume 2014, Article ID 631013, 20 pages,
http://dx.doi.org/10.1155/2014/631013
Reference Example 2: New lignocellulose pretreatments using cellulose solvents: a review, Noppadon Sathitsuksanoh, Anthe George and YH Percival Zhang, J Chem Technol Biotechnol 2013; 88: 169-180.

The weight of plant fiber is as light as 1/5 of steel, the strength of plant fiber is more than 5 times that of steel, and the thermal expansion of plant fiber is 1/50 that of glass and has a low linear thermal expansion coefficient. There is also a technique for producing microfibrillated plant fibers (MFC) by mechanically or chemically defibrating plant fibers. MFC is a fiber having a fiber diameter of about 100 nm, a fiber length of about 5 μm or more, and a specific surface area of about 250 m ² / g. MFC is higher in strength than unfiltrated plant fibers.

  Patent Document 1 describes a microfibrillated plant fiber obtained by mechanically defibrating pulp containing lignin. Patent Document 2 describes surface acylated cellulose or surface acylated lignocellulose as a compounding material such as a resin and a rubber component. The technique of Patent Document 2 is a technique for acylating a hydroxyl group present on the surface of cellulose or lignocellulose.

  In Non-Patent Document 1, in order to use lignin in lignocellulose as a polymer material, phenols (for example, cresol) and lignocellulose are reacted with the presence of strong acid (sulfuric acid) to decompose lignocellulose. Has been disclosed which leads to a phenol derivative (lignophenol) and separates it. In this reaction, it is described that a lignin derivative (lignophenol) in which the carbon at the lignin α-position and the ortho-position carbon of the phenol are bound is produced, but the α-position-modified lignocellulose derivative and the production method thereof are disclosed. Not.

  Thus, until now, there is no literature regarding lignocellulose derivatives in which the α-position of the phenylpropane unit constituting the lignin is chemically modified (α-position-modified lignocellulose derivatives).

JP 2009-19200 Japanese Patent Laid-Open No. 9-221501

A NewType of Phenolic Lignin-based Network Polymer with the Structure-variable Function Composed of 1,1-Diarylpropane Units, Masamitsu Funaoka, Polymer International 47 (1998) 277-290

  An object of the present invention is to provide a chemically modified lignocellulose derivative that is lightweight, has high strength, has a low coefficient of linear thermal expansion, and can exhibit thermoplasticity.

  Another object of the present invention is to provide a fiber or fiber aggregate containing a chemically modified lignocellulose derivative, and a composition and a molded body containing the fiber or fiber aggregate.

  In order to solve the above-mentioned problems, the present inventors have made extensive studies on the chemical modification of lignocellulose, and as a result, selectively selected the α-position hydroxyl group of the phenylpropane unit constituting the lignin of lignocellulose by a specific reaction method. The α-position of the phenylpropane unit constituting lignin, which is lightweight, has high strength, and has a low coefficient of linear thermal expansion, is modified to a lignocellulose derivative (hereinafter referred to as “α”). Succeeded in obtaining a “position-modified lignocellulose derivative”.

  Furthermore, the α-position of the phenylpropane unit constituting the lignin is chemically modified by chemically modifying the hydroxyl group present in at least one of hemicellulose and / or cellulose constituting the α-position-modified lignocellulose derivative, In addition, hemicellulose and / or a lignocellulose derivative in which the hydroxyl group of cellulose is chemically modified (hereinafter also referred to as “lignocellulose double-modified product”) has been successfully obtained. The lignocellulose double-modified product was found to be excellent in stability and moldability.

  The present inventors have completed the present invention by further research based on such knowledge.

  That is, the present invention comprises the following α-modified lignocellulose derivative, lignocellulose double-modified product, fiber or fiber assembly containing α-modified lignocellulose derivative or lignocellulose double-modified product, and these fibers or fiber assembly. The present invention relates to a molded body, and a composition and a molded body including the fiber or the fiber assembly and a matrix material.

Item 1.
A chemically modified lignocellulose derivative comprising:
Α position of phenylpropane unit constituting lignin contained in lignocellulose,
General formula (1): R ¹ COO- (1)
An acyloxy group represented by
General formula (2): R ² O- (2)
And an oxy group represented by the general formula (3): R ³ S- (3)
A lignocellulose derivative modified with at least one characteristic group selected from the group consisting of thio groups represented by the formula: [In the formulas (1) to (3), R ^{1 to} R ³ are the same or different; An alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkidienyl group, a cycloalkenyl group, an alktrienyl group, an alkynyl group, an aryl group, a heteroaryl group, an aralkyl group, which may have a substituent , A heteroarylalkyl group, a heterocyclic group (heterocyclyl group), a heterocyclic alkyl group (heterocyclylalkyl group) or a hydrogen atom (provided that R ² and R ³ are not a hydrogen atom or an ethynyl group)].

Item 2.
R ^{1 to} R ³ in the formulas (1) to (3) are the same or different, and each may have a substituent, each having a C1-C17 alkyl group, a C4-C8 cycloalkyl group, C2 -C17 alkenyl group, C2-C8 alkynyl group (where R ² and R ³ are not ethynyl groups, respectively), C4-C8 cycloalkenyl group, C4-C17 alkidienyl group, C4-C8 cycloalkyl A chidienyl group, a C6-C17 alkyltrienyl group, a lower alkyl group-substituted aryl group, a pyridyl group, a lower alkyl group-substituted pyridyl group, a thienyl group, or a lower alkyl group-substituted thienyl group,
2. The lignocellulose derivative according to item 1.

Item 3.
The acyloxy group represented by the general formula (1) is formic acid, acetic acid, propionic acid, butyric acid, valeric acid, pivalic acid, hexanoic acid, heptanoic acid, octanoic acid, pelargonic acid, decanoic acid, undecylic acid, lauric acid, Saturated fatty acid selected from tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, margaric acid, stearic acid, nonadecylic acid and arachidic acid; selected from phenoxyacetic acid, 3-phenoxypropionic acid, 4-phenoxybutyric acid and 5-phenoxyvaleric acid Aromatic substituted saturated fatty acids; unsaturated carboxylic acids selected from acrylic acid and methacrylic acid; monounsaturated fatty acids selected from crotonic acid, myristoleic acid, palmitoleic acid, oleic acid and ricinoleic acid; sorbic acid, linoleic acid and eicosadiene Diunsaturated fatty acids selected from acids; linolenic acid, A triunsaturated fatty acid selected from norenic acid and eleostearic acid; a tetraunsaturated fatty acid selected from stearidonic acid and arachidonic acid; a pentaunsaturated fatty acid selected from boseopenaenoic acid and eicosapentaenoic acid; selected from docosahexaenoic acid and nisic acid Hexa-unsaturated fatty acids; from benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, salicylic acid, gallic acid (3,4,5-trihydroxybenzenecarboxylic acid), cinnamic acid (3-phenylprop-2-enoic acid) Aromatic carboxylic acid selected; dicarboxylic acid selected from oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid and maleic acid; glycine, β-alanine and ε-aminocaproic acid (6-aminohexanoic acid) An amino acid selected from: maleimide compound:

Phthalimide compounds:

A residue obtained by removing a hydrogen atom from a carboxy group of at least one compound selected from the group consisting of:
The oxy group represented by the general formula (2) is methanol, ethanol, a linear alcohol having 3 to 12 carbon atoms, isopropanol, isobutanol, cyclooxanol, allyl alcohol, benzyl alcohol, phenol, 4-methylphenol, Tetrahydrofurfuryl alcohol, a residue obtained by removing a hydrogen atom from the hydroxy group of at least one compound selected from the group consisting of glycolic acid lower alkyl esters,
The thio group represented by the general formula (3) is methanethiol, ethanethiol, linear alkanethiol having 3 to 12 carbon atoms, isopropanethiol, isobutanethiol, cyclooxanethiol, 2-propene-1-thiol , A residue obtained by removing a hydrogen atom from a thiol group of at least one compound selected from the group consisting of cyclohexanethiol, benzyl mercaptan, cyclohexanemethanethiol, and thiophenol.
2. The lignocellulose derivative according to item 1.

Item 4.
The hydroxyl group present in at least one of cellulose and hemicellulose contained in the lignocellulose derivative may have a substituent, saturated fatty acid, monounsaturated fatty acid, diunsaturated fatty acid, triunsaturated fatty acid, tetraunsaturated fatty acid. Saturated fatty acid, pentaunsaturated fatty acid, hexaunsaturated fatty acid, aromatic carboxylic acid, aromatic dicarboxylic acid, amino acid,
Maleimide compounds:

And phthalimide compounds:

Substituted with a residue obtained by removing a hydrogen atom from a carboxy group of at least one compound selected from the group consisting of:
Item 4. The lignocellulose derivative according to any one of Items 1 to 3.

Item 5.
The fiber or fiber assembly containing the lignocellulose derivative in any one of said claim | item 1-4.

Item 6.
6. A fiber or a fiber assembly containing the lignocellulose derivative according to item 5 that is microfibrillated.

Item 7.
A compression molded product of a fiber or a fiber assembly containing the lignocellulose derivative according to Item 5 or 6.

  The molded object obtained by compressing the fiber or fiber assembly containing the lignocellulose derivative of said claim | item 5 or 6.

Item 8.
7. A composition comprising a fiber or fiber assembly containing the lignocellulose derivative according to item 5 or 6 and a matrix material.

Item 9.
A molded article comprising the composition according to Item 8.

  A molded article obtained by molding the composition according to Item 8.

Item 10.
The α-position of the phenylpropane unit constituting lignin is
General formula (1): R ¹ COO- (1)
An acyloxy group represented by
General formula (2): R ² O- (2)
And an oxy group represented by the general formula (3): R ³ S- (3)
A method for producing a lignocellulose derivative modified with at least one characteristic group selected from the group consisting of thio groups represented by:
In the presence of chlorite or Lewis acid,
Lignocellulose and general formula (1 '): R ¹ COOH (1')
A carboxylic acid represented by
General formula (2 ′): R ² OH (2 ′)
And the alcohol represented by
General formula (3 '): R ³ SH (3')
A process comprising the step of reacting with at least one compound selected from the group consisting of thiols represented by the formula (1) to (3) and formulas (1 ′) to (3 ′) R ^{1 to} R ³ may be the same or different and each may have a substituent, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkidienyl group, a cycloalkydenyl group, an alktrienyl group Group, alkynyl group, aryl group, heteroaryl group, aralkyl group, heteroarylalkyl group, heterocyclic group (heterocyclyl group), heterocyclic alkyl group (heterocyclylalkyl group) or a hydrogen atom (provided that R ² and R ³ Is not a hydrogen atom or an ethynyl group)].

Item 11.
(A) The α-position of the phenylpropane unit constituting lignin is
General formula (1): R ¹ COO- (1)
An acyloxy group represented by
General formula (2): R ² O- (2)
And an oxy group represented by the general formula (3): R ³ S- (3)
Modified with at least one characteristic group selected from the group consisting of thio groups represented by:
(B) a hydroxyl group present in at least one of cellulose and hemicellulose,
General formula (1): R ¹ COO- (1)
A method for producing a lignocellulose derivative substituted with an acyloxy group represented by:
(a) in the presence of chlorite or Lewis acid,
Lignocellulose,
General formula (1 '): R ¹ COOH (1')
A carboxylic acid represented by
General formula (2 ′): R ² OH (2 ′)
And the alcohol represented by
General formula (3 '): R ³ SH (3')
Is reacted with at least one compound selected from the group consisting of thiols, and the α-position of the phenylpropane unit constituting the lignin is an acyloxy group represented by the general formula (1), the general formula (2 A process for producing a lignocellulose derivative modified with at least one characteristic group selected from the group consisting of an oxy group represented by formula (3) and a thio group represented by the general formula (3), and
(b) lignocellulose;
General formula (1 '): R ¹ COOH (1')
The hydroxyl group present in at least one of cellulose and hemicellulose is substituted with the acyloxy group represented by the general formula (1) by reacting with the acid chloride or acid anhydride of the carboxylic acid represented by A production method comprising a step of producing a lignocellulose derivative [in the formulas (1) to (3) and the formulas (1 ′) to (3 ′), R ^{1 to} R ³ are the same or different; Each of them may have a substituent, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkidienyl group, a cycloalkenyl group, an alktrienyl group, an alkynyl group, an aryl group, a heteroaryl group, an aralkyl group. group, heteroarylalkyl group, a Hajime Tamaki (heterocyclyl group), showing a heterocyclic alkyl group (heterocyclylalkyl group) or a hydrogen atom (provided that, R ² and R ³ are a hydrogen atom, a ethynyl group B)].

Item 12.
General formula (1 ′): R ¹ COOH (1 ′)
The carboxylic acid represented by may have a substituent, saturated fatty acid, monounsaturated fatty acid, diunsaturated fatty acid, triunsaturated fatty acid, tetraunsaturated fatty acid, pentaunsaturated fatty acid, hexaunsaturated fatty acid, Aromatic carboxylic acid, aromatic dicarboxylic acid, amino acid,
Maleimide compounds:

And phthalimide compounds:

Is at least one compound selected from the group consisting of:
Item 12. The method for producing a lignocellulose derivative according to Item 11.

  According to the production method of the present invention, the α-position-modified lignocellulose derivative is selectively chemically modified at the α-position of the phenylpropane unit constituting the lignin.

  In the lignocellulose double-modified product of the present invention, in addition to the α-position of the phenylpropane unit constituting lignin being chemically modified, a hydroxyl group present in at least one of hemicellulose or cellulose constituting lignocellulose is further added. It is chemically modified.

  The fiber containing the α-modified lignocellulose derivative or / and the lignocellulose double-modified product of the present invention is light in weight, has high strength, has a low coefficient of linear thermal expansion, and is thermoplastic, like plant fibers. Can be expressed.

  In particular, the lignocellulose double-modified product of the present invention has a property (thermoplasticity) that softens and molds when heated and hardens again when cooled, as in general-purpose plastics, and can exhibit good processability. And the molded object processed in this way has the outstanding intensity | strength and thermal stability (low linear thermal expansion coefficient).

It is a figure showing the typical basic unit (phenylpropane unit) of lignin in lignocellulose. It is a figure showing the typical partial structure (β-0-4 type conjugate) of lignin in lignocellulose. Raw material (BM-NCTMP), the present invention α-modified lignocellulose derivative (Example 1a-1, lignocellulose derivative in which the lignin α-position is modified with an acetyloxy group), and the present invention double-modified lignocellulose derivative (Example) 2-1 is a diagram showing an IR absorption spectrum of a derivative in which the α-position is modified with an acetyloxy group and a sugar chain OH group such as hemicellulose is octanoylated (raw material is a black line, Example 1a-1 is A blue line, Example 2a-1 shows each absorption spectrum with a red line). It is a figure showing the HSQC-NMR spectrum of lignocellulose in the raw conifer derived groundwood pulp (NGP). It is a figure showing the HSQC-NMR spectrum of the lignocellulose derivative (Example 1b-1) by which the lignin (alpha) position of the lignocellulose in the raw conifer pulp (NGP) of a raw material was modified by the acetyloxy group. The signal of Hα / Cα = 4.9 / 71.8 ppm originally present in the raw material (see FIG. 4) has decreased, and a signal of Hα / Cα based on the acetyloxy group has newly appeared at 6.1 / 74.7 ppm. It is a figure showing the HSQC-NMR spectrum of the lignocellulose derivative (Example 1b-5) by which the lignin (alpha) position of the lignocellulose in the raw material conifer derived groundwood pulp (NGP) was modified by the ethoxy group. When the lignin α-position is modified with an ethoxy group, a new Hα / Cα signal based on the ethoxy group appears around 4.5 / 80 ppm.

Hereinafter, the lignocellulose derivative of the present invention will be described in detail.

(1) α-modified lignocellulose derivative α-modified lignocellulose derivative of the present invention,
A chemically modified lignocellulose derivative comprising:
Α position of phenylpropane unit constituting lignin contained in lignocellulose,
General formula (1): R ¹ COO- (1)
An acyloxy group represented by
General formula (2): R ² O- (2)
And an oxy group represented by the general formula (3): R ³ S- (3)
Is modified with at least one characteristic group selected from the group consisting of thio groups represented by

  That is, the α-position-modified lignocellulose derivative is selected from the group consisting of the above formulas (1) to (3), the α-position hydroxyl group of the phenylpropane unit constituting the lignin in the lignocellulose containing lignin, cellulose and hemicellulose. It has a chemical structure substituted with at least one characteristic group.

In the above formulas (1) to (3), R ^{1 to} R ³ are the same or different and each may have a substituent, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkidienyl group. , Cycloalkenyl group, alktrienyl group, alkynyl group, aryl group, heteroaryl group, aralkyl group, heteroarylalkyl group, heterocyclic group (heterocyclyl group), heterocyclic alkyl group (heterocyclylalkyl group) or hydrogen atom Wherein R ² and R ³ are not a hydrogen atom or an ethynyl group.

  The lignocellulose derivative of the present invention is light, strong, and has a low coefficient of linear thermal expansion, as well as plant fibers, and can exhibit thermoplasticity.

  The terms used in this specification will be explained below.

  Lignocellulose is a complex hydrocarbon polymer that constitutes the cell walls of plants, and is known to be mainly composed of polysaccharide cellulose, hemicellulose, and lignin, which is an aromatic polymer.

Reference Example 1: Review Article Conversion of Lignocellulosic Biomass to Nanocellulose: Structure and Chemical Process HV Lee, SBA Hamid, and SK Zain, Scientific World Journal Volume 2014, Article ID 631013, 20 pages, http://dx.doi.org/ 10.1155 / 2014/631013
Reference example 2: New lignocellulose pretreatments using cellulose solvents: a review, Noppadon Sathitsuksanoh, Anthe George and YH Percival Zhang, J Chem Technol Biotechnol 2013; 88: 169-180
As used herein, the term “lignocellulose” means a lignocellulose or / and lignocellulose mixture, artificially modified lignocellulose or / and lignocellulose mixture of chemical structure naturally present in plants. To do. The mixture is, for example, a lignocellulose or / and a lignocellulose mixture having chemical structures contained in various pulps obtained from natural plants and obtained by mechanically and / or chemically treating the wood. .

  The lignocellulose referred to in the present specification is not limited to a naturally occurring lignocellulose having a chemical structure, and the lignin content in the lignocellulose is not limited. The lignocellulose referred to in the present specification includes any molecular weight lignocellulose having any chemical structure contained in the lignocellulose raw material described later and a mixture thereof.

  The term “lignocellulose derivative” used in the present specification is a polymer material chemically derived from the above-mentioned lignocellulose as used herein, and is not limited to a material having a single chemical structure. Also included are mixtures of polymer compounds having various chemical structures and molecular weights in which cellulose is chemically modified.

(1-1) Raw Material of Lignocellulose As the raw material of the lignocellulose derivative, a fiber containing lignocellulose or a fiber aggregate containing lignocellulose can be used. The fiber aggregate containing lignocellulose includes fiber aggregates containing lignocellulose of any shape in addition to plant-derived pulp, wood flour, wood chips and the like.

  For the production of the lignocellulose derivative of the present invention, a plant raw material containing lignocellulose such as a plant-derived material can be used. Plant-derived materials such as wood, bamboo, hemp, jute and kenaf, and agricultural residue such as bagasse, firewood and beet pomace can be used as plant raw materials. These plant raw materials containing lignocellulose can be used in the form of flakes, powders, fibers, or the like. These raw materials are suitable for producing the lignocellulose derivative of the present invention.

  A typical example of the raw material for producing the lignocellulose derivative of the present invention is pulp. Pulp is obtained by processing a plant-derived material such as wood chemically or / and mechanically and removing fibers contained therein. This is because the content of hemicellulose and lignin is lowered depending on the degree of chemical and biochemical treatment of the plant-derived material, and the fiber is mainly composed of cellulose. Pulp is one of the “plant fiber aggregates” referred to in the present invention.

  As wood for pulp production, for example, sitka spruce, cedar, cypress, eucalyptus, acacia and the like can be used. For the production of the lignocellulose derivative, used paper such as used paper, deinked used paper, corrugated used paper, magazines, copy paper, etc. can also be used.

  As a raw material of the lignocellulose derivative, one kind of plant fiber or two or more kinds of plant fibers can be used in combination.

  Pulp can be obtained by treating plant raw materials by mechanical pulping, chemical pulping, or a combination of mechanical pulping and chemical pulping. The mechanical pulping method is a method of pulping by mechanical force such as a grinder or refiner while leaving lignin. The chemical pulping method is a method of pulping by adjusting the content of lignin using a chemical.

  As mechanical pulp (MP), groundwood pulp (GP), refiner GP (RGP), thermomechanical pulp (TMP), chemithermomechanical pulp (CTMP), bleached chemical thermomechanical pulp (BCTMP), etc. can be used.

  As the pulp produced by the combination of the mechanical pulping method and the chemical pulping method, chemimechanical pulp (CMP), chemiground pulp (CGP), semi-chemical pulp (SCP) and the like can be used. As the semi-chemical pulp (SCP), pulp produced by a sulfite method, a cold soda method, a kraft method, a soda method, or the like can be used.

  As the chemical pulp (CP), sulfite pulp (SP), soda pulp (AP), kraft pulp (KP), dissolving kraft pulp (DKP) and the like can be used.

  Deinked waste paper pulp, corrugated waste paper pulp, and magazine waste paper pulp mainly composed of mechanical pulp, chemical pulp and the like can also be used.

  Among these pulps, as a raw material for the lignocellulose derivative of the present invention, it is preferable to use a pulp made from coniferous trees because the fibers exhibit high strength. Further, the pulping method for plant raw materials can be applied without limitation as long as it is a pulping method in which lignin in the plant raw materials is not completely removed and lignin is appropriately present in the pulp.

  For example, a mechanical pulping method in which plant raw materials are mechanically pulped is preferable. As the pulp used for the production of the lignocellulose derivative, it is preferable to use mechanical pulp (MP) such as groundwood pulp (GP), refiner GP (RGP), thermomechanical pulp (TMP), chemithermomechanical pulp (CTMP).

  The lignocellulose derivative of the present invention, the fiber containing the lignocellulose, the lignocellulose used as a raw material for producing the fiber assembly, the lignocellulose fiber or the lignin content in the fiber assembly are such that these raw materials can be chemically modified. As long as the lignin is contained, the content is not limited.

  The content of lignin is preferably about 1 to 40% by weight, more preferably about 3 to 35% by weight, from the viewpoint of the fiber containing the lignocellulose derivative, strength of the fiber assembly, thermoplasticity, thermal stability, and the like. More preferably, it is about 5 to 35% by weight. The lignin content can be measured by the Klason method.

  The content of the lignin component in the α-modified lignocellulose derivative and lignocellulose double-modified product of the present invention is determined based on the lignin in the raw material pulp when the production raw material, for example, lignin in the pulp is not removed in the production process of these lignocellulose derivatives. It is almost the same as the content rate.

(1-2) Fiber or fiber assembly As used herein, the term “fiber” means a thin thread-like substance, and a thin thread-like structure of a structure that forms a living organism, which is taken out from the living organism. Or thread-like material obtained by physically or chemically treating it.

  As used herein, the term “fiber aggregate” refers to a collection of fibers as described above, and is obtained by physically or / and chemically treating pulp, wood flour, wood pieces, and the like. Is included in the fiber assembly.

  The raw material used for the production of the lignocellulose derivative of the present invention is preferably a fiber or a fiber assembly containing lignocellulose. The lignocellulose derivative is preferably in the form of a fiber or fiber aggregate.

  The fibers or fiber aggregates containing the lignocellulose derivative of the present invention can be formed into a compact by compression, preferably in the state of microfibrillation (to be described later) (compression molding).

  In the present specification, a molded product obtained by compressing a fiber or fiber assembly containing the lignocellulose derivative of the present invention is referred to as a “compressed molded product”. In particular, a molded product obtained by compressing under heating is referred to as a “hot-pressed product”. It is called a molded body.

(1-3) Microfibrillation (defibration treatment)
In this invention, it is preferable from the viewpoint of the moldability that the fiber or fiber aggregate containing the lignocellulose derivative is microfibrillated.

  In the present specification, microfibrillated lignocellulose may be abbreviated as “MFLC”, and microfibrillated lignocellulose derivative may be abbreviated as “MFLC derivative”.

  The cell wall of a plant is mainly composed of components composed of cellulose, hemicellulose and lignin (that is, lignocellulose).

  In the fine structure of the plant cell wall, about 40 cellulose molecules are usually bonded by hydrogen bonds to form cellulose microfibrils (single cellulose nanofibers), usually about 4-5 nm in width, and several cellulose microfibrils. They gather to form cellulose fine fibers (cellulose microfibril bundles).

  And it is known that hemicellulose exists in the space | interval between cellulose microfibrils, and the circumference | surroundings of a cellulose microfibril, and lignin exists in the state with which it filled with the space | interval between cellulose microfibrils.

  Microfibrillated lignocellulose (MFLC) can be prepared by fibrillating fibers or fiber aggregates containing lignocellulose such as pulp (plant fibers). As the defibrating method, for example, an aqueous suspension or slurry of a fiber or a fiber assembly containing lignocellulose is mechanically ground or beaten by a refiner, a high-pressure homogenizer, a grinder, a uniaxial or multiaxial kneader, a bead mill or the like. A method of defibration can be used. As the multiaxial kneader, a biaxial kneader is preferable.

  If necessary, the above defibrating methods can be combined and processed. As these defibrating methods, for example, the defibrating method described in JP-A-2009-19200 can be used.

  Microfibrillated lignocellulose (MFLC) is a fiber or fiber aggregate (for example, pulp, wood, wood flour, wood chip, etc.) fiber containing lignocellulose that has been unraveled (defibrated) to the nanosize level. It is.

  The average value of the fiber diameter (fiber width) of the MFLC fiber is preferably about 4 to 200 nm, and the average value of the fiber length is preferably about 5 μm or more. The average value of the fiber diameter of the MFLC fiber is more preferably about 4 to 150 nm, and further preferably about 4 to 100 nm. The average value of MFLC fiber diameter (average fiber diameter) and the average value of fiber length (average fiber length) are average values when measuring at least 50 or more MFLCs in the field of view of an electron microscope.

The specific surface area of MFLC is preferably about 70~300m ² / g, more preferably about 70 to 250 ² / g, about 100 to 200 m ² / g is more preferable. By increasing the specific surface area of MFLC, the contact area with the matrix material (described later) can be increased, and the strength of the composition containing MFLC and the matrix material can be improved. Further, MFLC does not aggregate in the matrix material of the composition and can improve the strength of the molded body.

MFLC has a high specific surface area (about 70 to 300 m ² / g), is lighter and has higher strength than steel. MFLC has less thermal deformation (low thermal expansion) than glass. MFLC has high strength and low thermal expansion, and is a useful material as a sustainable resource material. It is possible to produce a composite material having high strength and low thermal expansion by combining MFLC and a polymer material such as a matrix material.

  The microfibrillated lignocellulose derivative (MFLC derivative) of the present invention is obtained by chemically modifying the above MFLC by the method described later, or chemically modified MFLC fibers or chemically modified MFLC fiber aggregates, for example, It can be obtained by defibration by the defibration method described in -19200 publication.

  When a composite with a matrix material (described later) is prepared, the matrix material and fibers or fiber aggregates containing lignocellulose derivatives can be kneaded and microfibrillated in the matrix.

  The average value of the fiber diameter (fiber width) of the MFLC derivative fiber is preferably about 4 to 200 nm as in the case of MFLC, and the average value of the fiber length is preferably about 5 μm or more. The average fiber diameter of the MFLC derivative is more preferably about 4 to 150 nm, and further preferably about 4 to 100 nm. The average value of MFLC fiber diameter (average fiber diameter) and the average fiber length (average fiber length) can be obtained as an average value when measuring at least 50 or more MFLCs in the field of view of an electron microscope.

  When MFLC is used for production of the MFLC derivative, the average value of the fiber diameter (fiber width) of the MFLC derivative is substantially the same as that of MFLC unless the fibrillation step is performed.

(1-4) α position of the phenylpropane unit constituting lignin (lignin α position)
Lignin in lignocellulose is considered to form a complex with cellulose or hemicellulose. Lignin has a variety of bond modes between molecules, and the basic unit is a phenylpropane unit shown in FIG. 1 as a basic skeleton.

The most abundant lignin is 2- (2-methoxyphenoxy) -1- (3-methoxy-4oxyphenyl) -1,3-propanediol (in the chemical formula of FIG. 1, R ₁ = R ₂ = It is a β-0-4 type conjugate (FIG. 2) having H) as a basic unit. This binding mode accounts for 50 to 70% of the total lignin, and a treatment method that preferentially cleaves this bond is adopted in an industrial lignin decomposition step.

Reference: http://www.jst.go.jp/pr/announce/20150109/, Plant Biotechnol J. 2015 Jan 8. doi: 10.1111 / pbi.12316. [Epub ahead of print]
Lignin in lignocellulose has phenylpropane units as the basic skeleton.

The α-position-modified lignocellulose derivative of the present invention is
A chemically modified lignocellulose derivative comprising:
The carbon atom at the α-position (that is, benzyl position) of the phenylpropane unit constituting lignin contained in lignocellulose is modified. A hydroxy group (—OH) is present at the α-position (hereinafter also referred to as “lignin α-position”) of the phenylpropane unit constituting the lignin contained in the lignocellulose, but the lignin α in the lignocellulose derivative of the present invention is present. In the place
General formula (1): R ¹ COO- (1)
An acyloxy group represented by
General formula (2): R ² O- (2)
And an oxy group represented by the general formula (3): R ³ S- (3)
And at least one characteristic group selected from the group consisting of thio groups represented by:

In the above formulas (1) to (3), R ^{1 to} R ³ are the same or different and each may have a substituent, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkidienyl group. , Cycloalkenyl group, alktrienyl group, alkynyl group, aryl group, heteroaryl group, aralkyl group, heteroarylalkyl group, heterocyclic group (heterocyclyl group), heterocyclic alkyl group (heterocyclylalkyl group) or hydrogen atom Wherein R ² and R ³ are not a hydrogen atom or an ethynyl group.

  The lignocellulose derivative of the present invention is characterized by having a group represented by the above general formula (1), (2) or (3) at the lignin α-position. The method for producing the lignocellulose derivative of the present invention will be described later. In the method for producing a lignocellulose derivative of the present invention (described later), the lignin α-position characteristic group is the above-mentioned general formula (1), (2) or (3), wherein the lignin α-position hydroxy group in the raw lignocellulose is It is presumed that the group was substituted with the indicated group, but the exact reaction mechanism has not been elucidated and is currently unknown.

R ^{1 to} R ³ in the above formulas (1) to (3) are the same or different and each may have a substituent, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkidienyl group. , Cycloalkenyl group, alktrienyl group, alkynyl group, aryl group, heteroaryl group, aralkyl group, heteroarylalkyl group, heterocyclic group (heterocyclyl group), heterocyclic alkyl group (heterocyclylalkyl group) or hydrogen atom Wherein R ² and R ³ are not a hydrogen atom or an ethynyl group.

  The alkyl group, alkenyl group, alkidienyl group, and alktrienyl group may be linear or branched.

When R ^{1 to} R ³ in the formulas (1) to (3) are alkyl groups, they may have a substituent, and a C1-C17 alkyl group is preferable. In particular, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, pival group (tert-butyl group, (CH ₃ ) ₃ C-), pentyl group, hexyl group, heptyl group, octyl group, nonyl Group, undecanyl group, tridecanyl group, pentadecanyl group, and heptadecanyl group (CH ₃ (CH ₂ ) _16- ) are preferable.

When R ^{1 to} R ³ in the formulas (1) to (3) are cycloalkyl groups, they may have a substituent, and a C4-C8 cycloalkyl group is preferable. There are a cyclobutyl group, a cyclopentyl group, a cyclohexyl group and the like.

When R ^{1 to} R ³ in the formulas (1) to (3) are alkenyl groups, they may have a substituent, and a C2-C17 alkenyl group is preferable. The general formula is C _n H _2n-1 −, which is on an unsaturated carbon atom such as a vinyl group (CH ₂ = CH-), but saturated carbon such as an allyl group (CH ₂ = CHCH _2- ). It may be on an atom. In addition, there are propenyl group, isopropenyl group, 2-methyl-1-propenyl group, 2-methylallyl group, 2-butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group and the like.

When R ^{1 to} R ³ in the formulas (1) to (3) are alkynyl groups, C2-C8 alkynyl groups (wherein R ² and R ³ are not ethynyl groups (HC≡C-), respectively) preferable. Of these, a 2-propynyl group is particularly preferred.

When R ^{1 to} R ³ in the formulas (1) to (3) are cycloalkenyl groups, they may have a substituent, and a C4-C8 cycloalkenyl group is preferable. Examples include a cyclobutenyl group, a 2-cyclopenten-1-yl group, a 2-cyclohexen-1-yl group, and a 3-cyclohexen-1-yl group.

When R ^{1 to} R ³ in the formulas (1) to (3) are alkidienyl groups, they may have a substituent, and C4-C17 alkidienyl groups are preferred. 1,3-butadienyl group (CH ₂ ═CH—CH═CH—) and the like.

When R ^{1 to} R ^{3 in} formulas (1) to (3) are a cycloalkenyl group, they may have a substituent, and a C4-C8 cycloalkenyl group is preferred. And cyclopentadienyl group.

When R ^{1 to} R ³ in the formulas (1) to (3) are alktrienyl groups, they may have a substituent, and a C6-C17 alktrienyl group is preferable. Hexatrienyl group _{(CH 2 = CH-CH =} CH-CH = CH-), heptatrienyl group, there is octatrienyl group.

When R ^{1 to} R ³ in the formulas (1) to (3) are aryl groups, they may have a substituent, and a phenyl group (C ₆ H ₅ —) is particularly preferable.

When R ^{1 to} R ^{3 in} formulas (1) to (3) are aralkyl groups, they may have a substituent, and substituted with an aryl group such as a benzyl group (phenylmethyl group, C ₆ H ₅ CH ₂ —) A lower alkyl group is preferred.

  As used herein, “lower” means “having 1 to 5 carbon atoms”.

  For example, the “lower alkyl group” is an alkyl group having 1 to 5 carbon atoms, and is a straight chain such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, or a pentyl group. Or a branched alkyl group.

When R ^{1 to} R ³ in the formulas (1) to (3) are heteroaryl groups, they may have a substituent, such as a pyridyl group, a lower alkyl group-substituted pyridyl group, a thienyl group, and a lower alkyl group-substituted thienyl group. , An indolyl group, or a lower alkyl group-substituted indolyl group is preferred.

As the substituent that R ^{1 to} R ^{3 in} formulas (1) to (3) may have, a lower alkyl group is preferable.

General formula (1): R ¹ COO- (1)
The lignin α-position of the lignocellulose derivative of the present invention is in particular represented by the general formula (1): R ¹ COO- (1)
It is preferable to have an acyloxy group represented by (R ¹ is the same as above).

The acyloxy group represented by the general formula (1) is formic acid, acetic acid, propionic acid, butyric acid, valeric acid, pivalic acid, hexanoic acid (caproic acid), heptanoic acid (enanthic acid), octanoic acid (caprylic acid), pelargon Saturated fatty acids selected from acids, decanoic acid (capric acid), undecyl acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, margaric acid, stearic acid, nonadecylic acid and arachidic acid;
An aromatic substituted saturated fatty acid selected from phenoxyacetic acid, 3-phenoxypropionic acid, 4-phenoxybutyric acid, 5-phenoxyvaleric acid;
An unsaturated carboxylic acid selected from acrylic acid and methacrylic acid;
Monounsaturated fatty acids selected from crotonic acid, myristoleic acid, palmitoleic acid, oleic acid and ricinoleic acid;
A diunsaturated fatty acid selected from sorbic acid, linoleic acid and eicosadienoic acid;
A triunsaturated fatty acid selected from linolenic acid, pinolenic acid and eleostearic acid;
A tetraunsaturated fatty acid selected from stearidonic acid and arachidonic acid;
Pentaunsaturated fatty acids selected from bosepentaenoic acid and eicosapentaenoic acid; hexaunsaturated fatty acids selected from docosahexaenoic acid and nisic acid;
Aromatic carboxylic acids selected from benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, salicylic acid, gallic acid (3,4,5-trihydroxybenzenecarboxylic acid), and cinnamic acid (3-phenylprop-2-enoic acid) Acid; dicarboxylic acid selected from oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid and maleic acid;
An amino acid selected from glycine, β-alanine and ε-aminocaproic acid (6-aminohexanoic acid);
Maleimide compounds:

Phthalimide compounds:

A residue obtained by removing a hydrogen atom from a carboxyl group of at least one compound selected from the group consisting of

The acyloxy group represented by the general formula (1) is particularly selected from acetic acid, propionic acid, pivalic acid, capric acid (decanoic acid), caprylic acid (octanoic acid), lauric acid, myristic acid, palmitic acid and stearic acid Saturated fatty acids;
An aromatic substituted carboxylic acid selected from phenoxyacetic acid, 3-phenoxypropionic acid, an aromatic substituted saturated fatty acid, benzoic acid and phthalic acid;
A residue obtained by removing a hydrogen atom from a carboxy group of at least one compound selected from the group consisting of an unsaturated carboxylic acid selected from crotonic acid, acrylic acid, methacrylic acid, oleic acid, and linoleic acid is preferable.

General formula (2): R ² O- (2)
The oxy group represented by the general formula (2) is preferably one having less steric hindrance from the viewpoint of reactivity when producing the α-modified lignocellulose derivative of the present invention by reacting at the lignin α-position of lignocellulose. . The oxy group is methanol, ethanol, linear alcohol having 3 to 12 carbon atoms, isopropanol, isobutanol, cyclooxanol, allyl alcohol, benzyl alcohol, phenol, 4-methylphenol, tetrahydrofurfuryl alcohol, lower alkyl glycolate. A residue obtained by removing a hydrogen atom from a hydroxy group of at least one compound selected from the group consisting of esters is preferred.

General formula (3): R ³ S- (3)
From the viewpoint of reactivity when producing the α-position-modified lignocellulose derivative of the present invention by reacting the thio group represented by the general formula (3) at the lignin α-position of lignocellulose, those having less steric hindrance are preferable. .

  The thio group is from methanethiol, ethanethiol, straight chain alkanethiol having 3 to 12 carbon atoms, isopropanethiol, isobutanethiol, 2-propene-1-thiol, cyclohexanethiol, benzyl mercaptan, cyclohexanemethanethiol, thiophenol. A residue obtained by removing a hydrogen atom from a thiol group of at least one compound selected from the group consisting of

(1-5) Degree of lignin α-position modification (also called α-position substitution degree or DSα for convenience)
The α-position (ie, lignin α-position) of the phenylpropane unit constituting the lignin contained in the lignocellulose derivative of the present invention has at least one characteristic group selected from the group consisting of the general formulas (1) to (3). Have.

  The degree to which the lignin α-position is modified by these characteristic groups is referred to as the α-position modification degree (for convenience, substitution degree or DSα). The degree of α-position modification (DSα) is as defined in the Examples section below. The α-position modification degree can be measured by various analysis methods such as FT-IR and NMR.

  The maximum α-position modification degree depends on the amount of lignin in the lignocellulose used, but is about 0.5.

  The degree of α-position modification substituted with at least one substituent selected from the group consisting of general formulas (1) to (3) is preferably about 0.01 to 0.5, and more preferably about 0.06 to 0.4. By setting the degree of α-position modification to about 0.01 to 0.5, the reaction time and the amount of reagent used can be reduced, and the effect of improving the thermal stability of the lignocellulose derivative can be obtained.

  Since the lignocellulose derivative of the present invention has a specific modifying group, particularly at the lignin α-position, like a general-purpose plastic, it softens when heated and becomes easy to mold, and becomes hard again when cooled (thermoplastic). Have good processability.

(2) Lignocellulose double-modified product
The cellulose in the α-modified lignocellulose derivative and the derivative in which the hydroxyl group in hemicellulose is modified are called a lignocellulose double-modified product.

The lignocellulose double-modified product of the present invention is a chemically modified lignocellulose derivative, (A) in addition to the modification of the lignocellulose lignin α-position,
(B)
The hydroxyl group present in at least one of the cellulose and hemicellulose constituting the α-modified lignocellulose derivative (that is, the sugar chain hydroxyl group of the α-modified lignocellulose derivative) is saturated fatty acid, unsaturated carboxylic acid, monounsaturated fatty acid , Diunsaturated fatty acids, triunsaturated fatty acids, tetraunsaturated fatty acids, pentaunsaturated fatty acids, hexaunsaturated fatty acids, aromatic carboxylic acids, dicarboxylic acids, amino acids,
Maleimide compounds:

Phthalimide compounds:

It is preferably substituted by a residue obtained by removing a hydrogen atom from a carboxy group of at least one compound selected from the group consisting of

  Saturated fatty acids include formic acid, acetic acid, propionic acid, butyric acid, valeric acid, pivalic acid, hexanoic acid (caproic acid), heptanoic acid (enanthic acid), octanoic acid (caprylic acid), pelargonic acid, decanoic acid (capric acid) Undecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, margaric acid, stearic acid, nonadecylic acid and arachidic acid are preferred.

  As the unsaturated carboxylic acid, acrylic acid, methacrylic acid and the like are preferable.

  As the monounsaturated fatty acid, crotonic acid, myristoleic acid, palmitoleic acid, oleic acid, ricinoleic acid and the like are preferable.

  As the diunsaturated fatty acid, sorbic acid, linoleic acid, eicosadienoic acid and the like are preferable.

  As the triunsaturated fatty acid, linolenic acid, pinolenic acid, eleostearic acid and the like are preferable.

  The tetraunsaturated fatty acid is preferably selected from stearidonic acid and arachidonic acid.

  As the pentaunsaturated fatty acid, boseopentaenoic acid, eicosapentaenoic acid and the like are preferable.

  As the hexaunsaturated fatty acid, docosahexaenoic acid, nisic acid and the like are preferable.

  Aromatic carboxylic acids include benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, salicylic acid, gallic acid (3,4,5-trihydroxybenzenecarboxylic acid), cinnamic acid (3-phenylprop-2-enoic acid) Etc.) are preferred.

  As the dicarboxylic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, maleic acid and the like are preferable.

  As the amino acid, glycine, β-alanine, ε-aminocaproic acid (6-aminohexanoic acid) and the like are preferable.

  A compact can be obtained by compressing the fiber or fiber aggregate (lignocellulose-containing material) containing the lignocellulose double-modified product. This is referred to as a compression molded product of a fiber or a fiber assembly containing a lignocellulose derivative.

(3) Production method of α-position-modified lignocellulose derivative The α-position-modified lignocellulose derivative of the present invention is an acyloxy group represented by the general formula (1) at the α-position of the phenylpropane unit constituting the lignin, It has at least one characteristic group selected from the group consisting of an oxy group represented by the formula (2) and a thio group represented by the general formula (3).

The α-position of the phenylpropane unit constituting the (A) lignin of the present invention is
General formula (1): R ¹ COO- (1)
An acyloxy group represented by
General formula (2): R ² O- (2)
And an oxy group represented by the general formula (3): R ³ S- (3)
A method for producing a lignocellulose derivative modified with at least one characteristic group selected from the group consisting of thio groups represented by:
(a) in the presence of chlorite or Lewis acid,
Lignocellulose and general formula (1 '): R ¹ COOH (1')
A carboxylic acid represented by
General formula (2 ′): R ² OH (2 ′)
And the alcohol represented by
General formula (3 '): R ³ SH (3')
And a step of reacting with at least one compound selected from the group consisting of thiols represented by the formula:

In the formulas (1) to (3) and the formulas (1 ′) to (3 ′), R ^{1 to} R ³ are the same or different and each may have a substituent, an alkyl group, a cycloalkyl Group, alkenyl group, cycloalkenyl group, alkidienyl group, cycloalkydenyl group, alktrienyl group, alkynyl group, aryl group, heteroaryl group, aralkyl group, heteroarylalkyl group, heterocyclic group (heterocyclyl group), heterocyclic A ring alkyl group (heterocyclylalkyl group) or a hydrogen atom is shown. However, R ² and R ³ are not a hydrogen atom or an ethynyl group.

  The α-position-modified lignocellulose derivative uses a raw material containing lignocellulose, and selectively modifies the α-position of the phenylpropane unit constituting the lignin of the lignocellulose (that is, also referred to as benzyl position or lignin α-position). Can be manufactured.

  That is, the α-position of the phenylpropane unit constituting the lignin of lignocellulose is represented by the acyloxy group represented by the general formula (1), the oxy group represented by the general formula (2), and the general formula (3). It can be produced by selectively modifying with at least one characteristic group selected from the group consisting of thio groups.

  In the production method of the present invention, the characteristic group at the lignin α-position of the lignocellulose derivative of the present invention is such that the hydroxy group at the lignin α-position in the raw lignocellulose is represented by the above general formula (1), (2) or (3). Presumably substituted with the indicated group, the mechanism of its formation is currently unknown. It is confirmed by instrumental analysis (HSQC-NMR, etc.) that the lignocellulose derivative of the present invention has a group represented by the above general formula (1), (2) or (3) at the lignin α-position.

  For example, when comparing the HSQC-NMR spectrum of the lignocellulose derivative of the present invention in which the lignin α-position of the raw conifer-derived groundwood pulp (NGP) is modified with an acetyloxy group, compared with that of the raw material, the lignocellulose derivative of the present invention The signal of Hα / Cα = 4.9 / 71.8 ppm (see Fig. 4) present in the raw material decreased, and a new signal of Hα / Cα based on the acetyloxy group appeared at 6.1 / 74.7 ppm (see Fig. 5). ). This confirms the progress of the reaction of lignin to the α-position.

Further, in the IR analysis, the raw lignocellulose has no absorption peak due to stretching vibration of the carbonyl group of the acetyloxy group (C = O) in the vicinity of 1730 cm- ¹ , but when the lignin α-position is modified with the acetyloxy group, An absorption peak based on the stretching vibration of the carbonyl group (C═O) of the acetyloxy group appears at 1730 cm ⁻¹ (see FIG. 3).

  As a raw material containing lignocellulose, it is preferable to use plant fibers (pulp) containing lignocellulose, that is, fibers or fiber aggregates containing lignocellulose. As the fiber assembly, plant-derived pulp, wood powder, wood chips and the like are preferable. In addition, fiber aggregates containing lignocellulose of any shape can be used. Lignocellulose is not limited to naturally occurring lignocellulose, and the content of lignocellulose is not limited.

  As the fiber or fiber aggregate containing lignocellulose, at least one containing lignin, cellulose and hemicellulose can be used as a raw material for the lignocellulose derivative. As described above, lignin has a hydroxyl group at the α-position (ie, benzyl position) of the phenylpropane unit constituting the lignin.

  Therefore, if the pulp treated mechanically and / or chemically is a fiber or a fiber assembly containing lignocellulose as long as it also contains a lignin partial structure, this is the α-modified lignocellulose derivative of the present invention. Can be used as raw material.

  The α-position-modified lignocellulose can be produced by the following method a or b.

  α-modified lignocellulose comprises a fiber or fiber aggregate (lignocellulose-containing raw material) containing lignocellulose in the presence of chlorite (method a) or in the presence of Lewis acid (method b), lignin It can be produced by reacting compounds used for the modification of the α-position (hereinafter, these compounds are collectively referred to as “modifiers”). Specifically, it is preferable to use carboxylic acid, alcohol and thiol (mercaptan) represented by the following general formulas (1 ') to (3') as the modifying agent.

Α position of phenylpropane unit constituting lignin,
General formula (1): R ¹ COO- (1)
In order to modify with an acyloxy group represented by
General formula (1 '): R ¹ COOH (1')
The carboxylic acid represented by these is used.

Α position of phenylpropane unit constituting lignin,
Formula (2): R ² O- (2)
In order to modify with an oxy group represented by
General formula (2 ′): R ² OH (2 ′)
The alcohol represented by is used.

Α position of phenylpropane unit constituting lignin,
Formula (3): R ³ S- (3)
In order to modify with a thio group represented by
General formula (3 '): R ³ SH (3')
The thiol represented by this is used.

In the modifying groups represented by the general formulas (1) to (3) and in the modifying agents represented by the general formulas (1 ′) to (3 ′), R ^{1 to} R ³ are the same as described above, The same or different, each may have a substituent, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkidienyl group, a cycloalkydenyl group, an alktrienyl group, an alkynyl group, an aryl group, A heteroaryl group, an aralkyl group, a heteroarylalkyl group, a heterocyclic group (heterocyclyl group), a heterocyclic alkyl group (heterocyclylalkyl group) or a hydrogen atom (provided that R ² and R ³ are a hydrogen atom or an ethynyl group) Absent).

(3-1) Method a: Method for producing α-modified lignocellulose derivative using chlorite
In the method a, an α-position-modified lignocellulose derivative can be produced by reacting a fiber or a fiber assembly containing lignocellulose with the modifier in the presence of chlorite.

  This reaction is preferably carried out by suspending the fiber or fiber aggregate containing lignocellulose in a solvent, dissolving or dispersing the modifier, and stirring.

  Chlorites include alkali metal chlorites such as sodium chlorite, potassium chlorite and lithium chlorite, and chlorite such as magnesium chlorite, barium chlorite and calcium chlorite. Preference is given to using alkaline earth metal salts. As the chlorite, it is preferable to use an alkali metal chlorite because it is stable in a solvent and has good applicability to a reaction, and it is more preferable to use sodium chlorite. preferable.

  As the solvent, a solvent that dissolves the chlorite can be used. As the solvent, it is preferable to use a mixed solvent of water and a water-soluble aprotic solvent. For example, it is preferable to use a mixed solvent of water and N-methylpyrrolidone (NMP), a mixed solvent of water and N, N-dimethylformamide (DMF), a mixed solvent of water and dioxane, or the like.

  The amount of chlorite used can be appropriately adjusted according to the reactivity of the modifying agent with respect to the α-position (lignin α-position) of the phenylpropane unit constituting lignin and the target modification degree. The amount of chlorite used is preferably about 0.1 to 1.0 equivalent with respect to the α-position hydroxyl group of the phenylpropane unit constituting the lignin in the lignocellulose contained in the raw fiber or fiber assembly. The amount of chlorite used is more preferably about 0.3 to 0.6 equivalents.

  The amount of the modifier such as carboxylic acid, alcohol, and thiol represented by the above general formulas (1 ′) to (3 ′) is the reactivity and purpose of the modifier with respect to the α-position of the phenylpropane unit constituting lignin. It can adjust suitably according to the modification grade to do. The amount of the modifier used is preferably about 0.05 to 300 equivalents with respect to the α-position hydroxyl group of the phenylpropane unit constituting the lignin in the lignocellulose contained in the raw fiber or fiber assembly. As for the usage-amount of a modifier, about 0.1-100 equivalent is more preferable.

  The carboxylic acid represented by the general formula (1 ') used as the modifier is liquid at room temperature (for example, acetic acid) can be used as a solvent. In this case, the modifier is used in a large excess with respect to the α-position hydroxyl group of the phenylpropane unit constituting the lignin in the lignocellulose, but there is no particular problem.

  The reaction temperature and reaction time can be appropriately adjusted according to the reactivity of the modifying agent with respect to the α-position of the phenylpropane unit constituting the lignin and the target modification degree. The reaction temperature is preferably adjusted in the range of room temperature to the boiling point of the solvent. The reaction time is preferably about 1 to 24 hours.

(3-2) Method b: Method for producing α-modified lignocellulose derivative using Lewis acid
In the method b, α-modified lignocellulose can be produced by reacting a fiber or fiber aggregate containing lignocellulose with the modifier in the presence of a Lewis acid.

  In the reaction, when the modifier (carboxylic acid, alcohol, thiol, etc.) is a liquid component at room temperature, these modifiers can be used as a solvent. The reaction is preferably performed while suspending the fiber or fiber aggregate containing lignocellulose in the solvent of these modifiers and stirring.

  In the reaction, when the modifier is a solid component at room temperature, it is preferable to use a non-nucleophilic solvent such as chloroform or dichloromethane. The reaction is preferably performed by suspending a fiber or fiber aggregate containing lignocellulose in these solvents, dissolving or dispersing the modifier, and stirring.

Lewis acids include boron trifluoride ether complex (BF ₃ -Et ₂ O), boron trifluoride acetonitrile complex (BF ₃ · CH ₃ CN), boron trifluoride acetic acid complex (BF ₃ (CH ₃ COOH) ₂ It is preferred to use a water-stable Lewis acid such as Further, it is preferable to use a metal salt of trifluoromethanesulfonic acid such as ytterbium (III) trifluoromethanesulfonate (C ₃ F ₉ O ₉ S ₃ Yb · xH ₂ O).

  The amount of Lewis acid used can be appropriately adjusted according to the reactivity of the modifying agent with respect to the α-position of the phenylpropane unit constituting lignin and the target modification degree. The amount of the Lewis acid used is preferably about 0.14 to 1 equivalent with respect to the α-position hydroxyl group of the phenylpropane unit constituting the lignin in the lignocellulose contained in the raw fiber or fiber assembly. The amount of Lewis acid used is more preferably about 0.2 to 0.5 equivalent.

  The amount of the modifier such as carboxylic acid, alcohol, and thiol represented by the above general formulas (1 ′) to (3 ′) is the reactivity and purpose of the modifier with respect to the α-position of the phenylpropane unit constituting lignin. It can adjust suitably according to the modification grade to do. The amount of the modifier used is preferably about 6 to 20 equivalents relative to the α-position hydroxyl group of the phenylpropane unit constituting the lignin in the lignocellulose contained in the raw fiber or fiber assembly. As for the usage-amount of a modifier, about 8-18 equivalent is more preferable.

  The reaction temperature and reaction time can be appropriately adjusted according to the reactivity of the modifying agent with respect to the α-position of the phenylpropane unit constituting the lignin and the target modification degree. The reaction temperature is preferably adjusted in the range of room temperature to the boiling point of the solvent. The reaction time is preferably about 1 to 2 weeks.

(3-3) Features of production method of α-position-modified lignocellulose derivative The production method (method a and method b) of the α-position-modified lignocellulose of the present invention is different from the conventional acylation method in the following points.

  Conventionally, an acid chloride or an acid anhydride is reacted with a lignocellulose-containing raw material in the presence of a base. This is called the conventional acylation method. In the conventional acylation method, the acylation reaction proceeds in the order of the primary hydroxyl group, secondary hydroxyl group, and hydroxyl group at the α-position (ie, benzyl position) of lignin in lignocellulose. Therefore, in the conventional acylation method, the reaction of polysaccharides (cellulose in lignocellulose, hemicellulose) and lignin to primary hydroxyl groups proceeds simultaneously.

  In the (Method a and Method b) of the present invention, a selective reaction is possible with respect to the hydroxyl group at the α-position (that is, benzyl position) of the phenylpropane unit constituting lignin in lignocellulose. Therefore, when the conventional acylation reaction is performed after the reaction of Method a or Method b of the present invention, the hydroxyl group at the α-position (that is, benzyl position) of the phenylpropane unit constituting lignin, in the lignocellulose It is possible to react in the order of primary hydroxyl group and secondary hydroxyl group.

  In other words, the α-position (ie benzyl position) of the phenylpropane unit constituting lignin is modified first by the reaction proceeding selectively only to the α-position (ie benzyl position) of the phenylpropane unit constituting lignin. It becomes possible to do.

  The α-modified lignocellulose derivative (reaction product) obtained by the methods a and b of the present invention is different from the reaction product obtained by reacting a lignocellulose-containing raw material by a conventional acylation reaction.

  After obtaining an α-position-modified lignocellulose derivative by the methods a and b of the present invention, a normal acylation reaction is carried out using an acylating agent having a modifying group different from the modifier used in the methods a and b. In addition to the modifying group at the α-position (lignin α-position, ie, benzyl position) of the phenylpropane unit constituting the lignin in lignocellulose, a lignocellulose polysaccharide (in lignocellulose with a modifying group different from this modifying group). It becomes possible to produce a lignocellulose derivative (ligno-modified double-modified product) in which cellulose or hemicellulose) is modified.

(3-4) α-position modification degree of α-position-modified lignocellulose derivatives
(Denoted as DSα. Sometimes called substitution degree for convenience.)
By using the modifier, the α-position of the phenylpropane unit constituting the lignin contained in the lignocellulose has at least one modifying group selected from the group consisting of the general formulas (1) to (3). The α-position modification degree modified with at least one modification group selected from the group consisting of the general formulas (1) to (3) (denoted as DSα; sometimes referred to as substitution degree for convenience) is preferably about 0.01 to 0.5. 0.06 to 0.45 is more preferable. The maximum value of the α-position modification degree (DSα) depends on the amount of lignin in the lignocellulose used, but is about 0.5.

  By setting the α-position modification degree to about 0.01 to 0.5, the reaction time and the amount of reagent used can be minimized, and the thermal stability of the lignocellulose derivative of the present invention can be improved. In addition, the crystallinity of the cellulose region in the α-modified lignocellulose derivative and lignocellulose double-modified product of the present invention can be maintained at the same level as the crystallinity in the raw material lignocellulose.

(4) Lignocellulose double-modified product ( lignocellulose derivative in which the hydroxyl group present in at least one of cellulose and hemicellulose in the α-position-modified lignocellulose derivative is acylated)
Lignocellulose contains cellulose and hemicellulose in addition to lignin.

  In the chemically modified lignocellulose derivative of the present invention, the hydroxyl group (sugar chain hydroxyl group of α-modified lignocellulose) in at least one of cellulose and hemicellulose contained in the α-modified lignocellulose derivative is further acylated. It is preferable.

  That is, it is preferable to acylate a hydroxyl group other than the hydroxyl group at the lignin α-position and originally present in lignocellulose, for example, a hydroxyl group of cellulose, a hydroxyl group of hemicellulose, or the like. By this additional acylation reaction, the thermal stability and thermoplasticity of the α-modified lignocellulose derivative obtained by the method a or b are further improved.

The α-position of the phenylpropane unit constituting the (A) lignin of the present invention is
General formula (1): R ¹ COO- (1)
An acyloxy group represented by
General formula (2): R ² O- (2)
And an oxy group represented by the general formula (3): R ³ S- (3)
Modified with at least one characteristic group selected from the group consisting of thio groups represented by:
(B) a hydroxyl group present in at least one of cellulose and hemicellulose,
General formula (1): R ¹ COO- (1)
The method for producing a lignocellulose derivative substituted with an acyloxy group represented by:
(a) in the presence of chlorite or Lewis acid,
Lignocellulose and general formula (1 '): R ¹ COOH (1')
A carboxylic acid represented by
General formula (2 ′): R ² OH (2 ′)
And the alcohol represented by
General formula (3 '): R ³ SH (3')
Is reacted with at least one compound selected from the group consisting of thiols, and the α-position of the phenylpropane unit constituting the lignin is an acyloxy group represented by the general formula (1), the general formula (2 A process for producing a lignocellulose derivative modified with at least one characteristic group selected from the group consisting of an oxy group represented by formula (3) and a thio group represented by the general formula (3), and
(b) Lignocellulose derivative obtained in the above step (a) and the general formula (1 ′): R ¹ COOH (1 ′)
The hydroxyl group present in at least one of cellulose and hemicellulose is substituted with the acyloxy group represented by the general formula (1) by reacting with the acid chloride or acid anhydride of the carboxylic acid represented by It includes a step of producing a lignocellulose derivative.

In the formulas (1) to (3) and the formulas (1 ′) to (3 ′), R ^{1 to} R ³ are the same or different and each may have a substituent, an alkyl group, a cycloalkyl Group, alkenyl group, cycloalkenyl group, alkidienyl group, cycloalkydenyl group, alktrienyl group, alkynyl group, aryl group, heteroaryl group, aralkyl group, heteroarylalkyl group, heterocyclic group (heterocyclyl group), heterocyclic A ring alkyl group (heterocyclylalkyl group) or a hydrogen atom is shown. However, R ² and R ³ are not a hydrogen atom or an ethynyl group.

  Step (a) is as described above.

  Since the above step (b) is an acylation reaction, considering the reaction mechanism, the lignocellulose derivative of the product contains a “hydrogen atom of the hydroxyl group present in the cellulose and hemicellulose as an acyl group (from a carboxylic acid to a hydroxy group). In this specification, for the sake of convenience, a lignocellulose derivative obtained by an acylation reaction is referred to as a “derivative in which a hydroxyl group is substituted with an acyloxy group”. Sometimes.

In the acylation reaction in step (b), the α-modified lignocellulose derivative obtained in step (a) is suspended in an anhydrous aprotic polar solvent capable of swelling, and in the presence of a base,
Formula (1 '): R ¹ COOH (1')
In represented by acid chloride of the carboxylic acid ^{(R 1 -C (= O)} -Cl) or acid anhydride ^{((R 1 -CO-O-} CO-R 1) can be carried out by reacting the.

In the acid chloride or acid anhydride of the carboxylic acid represented by the formula (1 ′) used in the acylation reaction in the above step (b), R ¹ may have a substituent, an alkyl group, a cyclo Alkyl group, alkenyl group, cycloalkenyl group, alkyldienyl group, cycloalkyldienyl group, alkyltrienyl group, alkynyl group, aryl group, heteroaryl group, aralkyl group, heteroarylalkyl group, heterocyclyl group, heterocyclylalkyl group Or a hydrogen atom is shown.

In the acid chloride or acid anhydride of the carboxylic acid represented by the formula (1 ′) used in the acylation reaction in step (b), when R ¹ is an alkyl group, it may have a substituent. As in the case where the lignin α-position hydroxy group of the lignin α-position is substituted with the group represented by the general formula (1), a C1-C17 alkyl group is preferred.

Similarly, when R ¹ is a cycloalkyl group, it may have a substituent, and a C4-C8 cycloalkyl group is preferred.

Similarly, when R ¹ is an alkenyl group, it may have a substituent, and a C2-C17 alkenyl group is preferred.

Similarly, when R ¹ is an alkynyl group, a C2-C8 alkynyl group is preferred.

Similarly, when R ¹ is a cycloalkenyl group, it may have a substituent, and a C4-C8 cycloalkenyl group is preferred.

Similarly, when R ¹ is an alkidienyl group, it may have a substituent and is preferably a C4-C17 alkidienyl group.

Similarly, when R ¹ is a cycloalkenyl group, it may have a substituent, and a C4-C8 cycloalkenyl group is preferred.

Similarly, when R ¹ is an alktrienyl group, it may have a substituent, and a C6-C17 alktrienyl group is preferred.

Similarly, when R ¹ is an aryl group, it may have a substituent, and a phenyl group (C ₆ H ₅ —) is particularly preferable.

Similarly, when R ¹ is an aralkyl group, it may have a substituent, and an aryl group-substituted lower alkyl group such as a benzyl group (phenylmethyl group, C ₆ H ₅ CH ₂ —) is preferred.

Similarly, when R ¹ is a heteroaryl group, it may have a substituent and may be substituted with a pyridyl group, a lower alkyl group-substituted pyridyl group, a thienyl group, a lower alkyl group-substituted thienyl group, an indolyl group, or a lower alkyl group. Indolyl groups are preferred.

As the substituent that R ¹ in formula (1) may have, a lower alkyl group is preferable.

  N-methylpyrrolidone, N, N-dimethylformamide and the like are preferable as the anhydrous aprotic polar solvent capable of swelling the α-position-modified lignocellulose derivative by the acylation reaction.

  As the base used in the acylation reaction, pyridine, N, N-dimethylaniline, sodium carbonate, sodium hydrogen carbonate and the like are preferable.

Carboxylic anhydride or carboxylic acid chloride (carboxylic acid anhydride or acid chloride represented by the general formula (1 ′)) used in the acylation reaction in the step (b) includes saturated fatty acid, unsaturated Carboxylic acid, monounsaturated fatty acid, diunsaturated fatty acid, triunsaturated fatty acid, tetraunsaturated fatty acid, pentaunsaturated fatty acid, hexaunsaturated fatty acid, aromatic carboxylic acid, dicarboxylic acid, amino acid (N-protected amino acid),
Maleimide compounds:

Phthalimide compounds:

An acid anhydride or acid chloride of at least one carboxylic acid selected from the group consisting of

  In the acylation reaction in step (b), acetic anhydride, acetyl chloride, octanoyl chloride or the like is preferably used.

  This acylation reaction is preferably performed with stirring at room temperature to 100 ° C., for example.

In the lignocellulose double-modified product of the present invention produced by the above method, a hydroxyl group present in at least one of cellulose and hemicellulose (hereinafter also referred to as “sugar chain hydroxyl group of double-modified product”) is a saturated fatty acid, Saturated carboxylic acid, monounsaturated fatty acid, diunsaturated fatty acid, triunsaturated fatty acid, tetraunsaturated fatty acid, pentaunsaturated fatty acid, hexaunsaturated fatty acid, aromatic carboxylic acid, dicarboxylic acid,
Maleimide compounds:

Phthalimide compounds:

It is preferably substituted by a residue obtained by removing a hydrogen atom from a carboxyl group of at least one compound selected from the group consisting of

Degree of acylation of sugar chain hydroxyl group in lignocellulose double modified product
(Denoted as DS _OH . Sometimes called substitution or modification)
The acylation degree (modification degree, DS _OH ) at the sugar chain hydroxyl group of the lignocellulose double-modified product of the present invention obtained by the acylation reaction of the α-modified lignocellulose derivative of the present invention is preferably about 0.05 to 2, preferably 0.1 to 1.7. More preferably, the degree is more preferably about 0.15 to 1.5. The maximum value of the degree of substitution (DS _OH ) depends on the lignin content of the lignocellulose used as the raw material, but is about 2.5.

By setting the degree of substitution (DS _OH ) to about 0.05 to 2, the maximum effect can be obtained by minimizing the reaction time and the amount of reagent used. The lignocellulose double-modified product obtained by acylation of the sugar chain hydroxyl group of the α-modified ligno-modified product is further improved in thermal stability and thermoplasticity.

The degree of substitution (DS _OH ) can be analyzed by various analysis methods such as elemental analysis, neutralization titration method, FT-IR, two-dimensional NMR ( ¹ H and ¹³ C-NMR).

  The fiber or fiber assembly containing the lignocellulose double-modified product of the present invention is lightweight, has strength, and has a low linear thermal expansion coefficient, similar to plant fibers.

  It is possible to produce a compact (compressed compact) by compressing the fiber or fiber aggregate containing the lignocellulose double-modified product of the present invention.

(5) Preparation of molded body (compression molded body of lignocellulose derivative of the present invention)
A compact can be easily prepared by compressing the fiber or fiber assembly containing the lignocellulose derivative of the present invention. This is also referred to as a compression molded product of a fiber or fiber assembly containing a lignocellulose derivative.

  In the present specification, the “α-position-modified lignocellulose derivative or / and lignocellulose double-modified product” is also collectively referred to as “lignocellulose derivative”.

  The fiber or fiber aggregate is a lignocellulose derivative (α-modified lignocellulose derivative) or / and α-modified ligno having an acyloxy group, an oxy group, a thio group or the like at the α-position of the phenylpropane unit constituting lignin. A lignocellulose derivative (lignocellulose double modified product) in which the sugar chain hydroxyl group of the cellulose derivative is acylated is included.

  Before molding, in order to obtain a uniform molding surface, a fiber or a fiber assembly containing a lignocellulose derivative is pulverized as necessary and then compression-molded under heating. As one method of pulverization, for example, ethanol or the like, preferably a solvent having a boiling point of 100 ° C. or less, is added to a fiber or a fiber assembly containing a lignocellulose derivative, and the solid content concentration is adjusted by stirring with a mixer or the like. A suspension is obtained. Next, the suspension may be dried by removing the solvent by means such as filtration and obtaining a molding material.

  In order to avoid thermal decomposition of the lignocellulose derivative, the molding is preferably performed at a temperature of about 150 to 200 ° C. with a compression pressure of a normal thermoplastic resin.

(6) Composition comprising lignocellulose derivative-containing fiber or fiber assembly and matrix material The fiber or fiber assembly containing the lignocellulose derivative of the present invention is combined with a matrix material (described later) to form a composite composition, It can also be set as the molded object which is excellent in. This composition comprises fibers containing lignocellulose derivatives (including fibrillated nanofibers) or a mixture of this fiber assembly and matrix material, or fibers containing lignocellulose derivatives (fibrillated nanofibers) Or a fiber material composition impregnated with a matrix material.

  It is already known that a composite having excellent strength can be obtained by combining a matrix material such as a polymer resin and chemically modified cellulose fibers (for example, chemically modified cellulose nanofibers).

  The fiber or fiber assembly containing the lignocellulose derivative of the present invention has fewer production steps from a plant raw material (for example, wood) and has a higher yield (yield based on weight) than known chemically modified cellulose fibers. Therefore, it can be expected that it can be produced at a lower cost per unit weight than known chemically modified cellulose fibers.

  Moreover, the composition containing a lignocellulose-containing fiber or fiber aggregate and a matrix material can be expected to be easier and less expensive to manufacture than a composition containing a conventional chemically modified cellulose fiber.

(6-1) Matrix Material The matrix material means a polymer precursor or a polymer precursor such as a monomer or oligomer thereof that fills the gaps between fibers, fiber masses or fiber aggregates (for example, nonwoven fabric). As the inorganic polymer of the matrix material, ceramics such as glass, silicate material, titanate material, etc., and cement can be used. The inorganic polymer of the matrix material can be formed, for example, by dehydration condensation reaction of alcoholate.

  As the organic polymer for the matrix material, natural polymers, synthetic polymers, rubber components, and the like can be used.

  Examples of the natural polymer include natural rubber, a regenerated cellulose polymer, a naturally-derived polymer such as cellophane and triacetyl cellulose, and a polymer obtained by chemically processing the same. Examples of the synthetic polymer include synthetic rubber, vinyl resin, polycondensation resin, polyaddition resin, addition condensation resin, and ring-opening polymerization resin.

  Examples of the vinyl resin include general-purpose resins such as polyolefin, vinyl chloride resin, vinyl acetate resin, fluororesin, and (meth) acrylic resin, engineering plastics obtained by vinyl polymerization, super engineering plastics, and the like. These may be a homopolymer or a copolymer of each monomer constituted in each resin.

  Examples of the polyolefin include homopolymers or copolymers such as ethylene, propylene, styrene, butadiene, butene, isoprene, chloroprene, isobutylene and isoprene, or cyclic polyolefins having a norbornene skeleton.

  Examples of the vinyl chloride resin include homopolymers or copolymers such as vinyl chloride and vinylidene chloride.

  The vinyl acetate resin is polyvinyl acetate, which is a homopolymer of vinyl acetate, polyvinyl alcohol, which is a hydrolyzate of polyvinyl acetate, polyvinyl acetal obtained by reacting vinyl acetate with formaldehyde or n-butyraldehyde, polyvinyl alcohol. And polyvinyl butyral obtained by reacting butylaldehyde and the like.

  Examples of the fluororesin include homopolymers or copolymers such as tetrachloroethylene, hexpropylene, chlorotrifluoroethylene, vinylidene fluoride, vinyl fluoride, and perfluoroalkyl vinyl ether.

  Examples of the (meth) acrylic resin include homopolymers or copolymers such as (meth) acrylic acid, (meth) acrylonitrile, (meth) acrylic acid ester, and (meth) acrylamides. In this specification, “(meth) acryl” means “acryl and / or methacryl”.

  Here, examples of (meth) acrylic acid include acrylic acid and methacrylic acid. Examples of (meth) acrylonitrile include acrylonitrile and methacrylonitrile.

  Examples of (meth) acrylic acid esters include (meth) acrylic acid alkyl esters, (meth) acrylic acid monomers having a cycloalkyl group, and (meth) acrylic acid alkoxyalkyl esters.

  Examples of (meth) acrylic acid alkyl esters include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth) Examples include benzyl acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, hydroxyethyl (meth) acrylate, and the like.

  Examples of the (meth) acrylic acid monomer having a cycloalkyl group include cyclohexyl (meth) acrylate and isobornyl (meth) acrylate.

  Examples of (meth) acrylic acid alkoxyalkyl esters include 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, and the like.

  (Meth) acrylamides include (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N -N-substituted (meth) acrylamides such as isopropyl (meth) acrylamide and Nt-octyl (meth) acrylamide.

  Examples of the polycondensation resin include amide resin and polycarbonate.

  Examples of amide resins include aliphatic amide resins such as 6,6-nylon, 6-nylon, 11-nylon, 12-nylon, 4,6-nylon, 6,10-nylon, 6,12-nylon, An aromatic polyamide such as an aromatic diamine such as phenylenediamine and an aromatic dicarboxylic acid such as terephthaloyl chloride or isophthaloyl chloride or a derivative thereof may be used.

  Polycarbonate refers to a reaction product of bisphenol A or its derivative bisphenol and phosgene or phenyl dicarbonate.

  Examples of the polyaddition resins include ester resins, U polymers, liquid crystal polymers, polyether ketones, polyether ether ketones, unsaturated polyesters, alkyd resins, polyimide resins, polysulfones, polyphenylene sulfides, and polyether sulfones. .

  Examples of ester resins include aromatic polyesters, aliphatic polyesters, and unsaturated polyesters.

  Examples of the aromatic polyester include a copolymer of a diol described later such as ethylene glycol, propylene glycol, 1,4-butanediol and an aromatic dicarboxylic acid such as terephthalic acid.

  Examples of the aliphatic polyester include copolymers of diols described below and aliphatic dicarboxylic acids such as succinic acid and valeric acid, homopolymers or copolymers of hydroxycarboxylic acids such as glycolic acid and lactic acid, and diols described below. And copolymers of aliphatic dicarboxylic acids and the above hydroxycarboxylic acids.

  Examples of the unsaturated polyester include diols described later, unsaturated dicarboxylic acids such as maleic anhydride, and copolymers with vinyl monomers such as styrene as necessary.

  Examples of the U polymer include copolymers composed of bisphenol A and its derivatives, bisphenols, terephthalic acid, isophthalic acid, and the like.

  The liquid crystal polymer is a copolymer of p-hydroxybenzoic acid and terephthalic acid, p, p'-dioxydiphenol, p-hydroxy-6-naphthoic acid, polyterephthalic acid ethylene, or the like.

  Examples of the polyether ketone include homopolymers and copolymers such as 4,4'-difluorobenzophenone and 4,4'-dihydrobenzophenone.

  Examples of the polyether ether ketone include copolymers of 4,4'-difluorobenzophenone and hydroquinone.

  Examples of the alkyd resin include copolymers composed of higher fatty acids such as stearic acid and palmitic acid, dibasic acids such as phthalic anhydride, and polyols such as glycerin.

  Examples of polysulfone include copolymers such as 4,4'-dichlorodiphenylsulfone and bisphenol A.

  Examples of polyphenyllene sulfide include copolymers such as p-dichlorobenzene and sodium sulfide.

  Examples of the polyethersulfone include polymers of 4-chloro-4'-hydroxydiphenylsulfone.

  Examples of polyimide resins include pyromellitic acid-type polyimides such as polymellitic anhydride and 4,4'-diaminodiphenyl ether, aromatic diamines such as anhydrous trimellitic acid chloride and p-phenylenediamine, and diisocyanate compounds described later. Copolymers composed of trimellitic acid type polyimide, biphenyl tetracarboxylic acid, 4,4'-diaminodiphenyl ether, biphenyl type polyimide consisting of p-phenylenediamine, benzophenone tetracarboxylic acid, 4,4'-diaminodiphenyl ether, etc. Benzophenone-type polyimide, bismaleimide, bismaleimide-type polyimide made of 4,4′-diaminodiphenylmethane, and the like.

  Examples of the polyaddition resin include urethane resin.

  The urethane resin is a copolymer of diisocyanates and diols.

  Diisocyanates include dicyclohexylmethane diisocyanate, 1,6-hexamethylene diisocyanate, isophorone diisocyanate, 1,3-cyclohexylene diisocyanate, 1,4-cyclohexylene diisocyanate, 2,4-tolylene diisocyanate, 2,6- Examples include tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 2,4′-diphenylmethane diisocyanate, 2,2′-diphenylmethane diisocyanate, and the like.

  The diols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentane. Diol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, trimethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, cyclohexanedimethanol, and other relatively low molecular weight diols, and polyester diol , Polyether diol, polycarbonate diol and the like.

  Examples of the addition condensation resin include phenol resin, urea resin, and melamine resin.

  Examples of the phenol resin include homopolymers or copolymers such as phenol, cresol, resorcinol, phenylphenol, bisphenol A, and bisphenol F.

  Urea resin and melamine resin are copolymers of formaldehyde, urea, melamine and the like.

  Examples of the ring-opening polymerization resin include polyalkylene oxide, polyacetal, and epoxy resin.

  Examples of the polyalkylene oxide include homopolymers or copolymers such as ethylene oxide and propylene oxide.

  Examples of polyacetals include copolymers of trioxane, formaldehyde, ethylene oxide, and the like.

  Examples of the epoxy resin include an aliphatic epoxy resin composed of a polyhydric alcohol such as ethylene glycol and epichlorohydrin, an aliphatic epoxy resin composed of bisphenol A and epichlorohydrin, and the like.

  Examples of rubber components include those of diene rubber components. Specifically, natural rubber (NR), butadiene rubber (BR), styrene-butadiene copolymer rubber (SBR), isoprene rubber (IR), butyl rubber. (IIR), acrylonitrile-butadiene rubber (NBR), acrylonitrile-styrene-butadiene copolymer rubber, chloroprene rubber, styrene-isoprene copolymer rubber, styrene-isoprene-butadiene copolymer rubber, isoprene-butadiene copolymer rubber And modified natural rubber such as chlorosulfonated polyethylene and epoxidized natural rubber (ENR), hydrogenated natural rubber, deproteinized natural rubber, and the like.

  Examples of the rubber component other than the diene rubber component include ethylene-propylene copolymer rubber, acrylic rubber, epichlorohydrin rubber, polysulfide rubber, silicone rubber, fluorine rubber, and urethane rubber. What is necessary is just to mix | blend suitably also in the blend ratio in the case of blending according to various uses.

  These matrix materials may be used individually by 1 type, and 2 or more types may be mixed and used for them.

(6-2) Other components The composition of the present invention includes, for example, a compatibilizing agent; a surfactant (other than the above); starches, in addition to the fiber or fiber aggregate containing the lignocellulose and the matrix material. Polysaccharides such as alginic acid; Natural proteins such as gelatin, glue and casein; Inorganic compounds such as tannin, zeolite, ceramics and metal powders; Colorants; Plasticizers; Fragrances; Pigments; Flow control agents; Leveling agents; Additives such as an inhibitor; an ultraviolet absorber; an ultraviolet dispersant; and a deodorant may be blended. As a content ratio of an arbitrary additive, it may be appropriately contained within a range not impairing the effects of the present invention.

(6-3) Composition of composition containing fiber or fiber aggregate and matrix material Including a lignocellulose derivative in a composition containing a fiber or fiber aggregate of the present invention and a matrix material. The content ratio of the fiber or fiber aggregate is preferably about 0.01 to 99.99% by weight, more preferably about 0.05 to 99.95% by weight, and still more preferably about 0.1 to 99.9% by weight.

  Since the fiber or fiber aggregate containing the lignocellulose derivative of the present invention is more thermoplastic than cellulose fibers, it can be molded by heating even if a small amount of thermoplastic matrix material is added.

  The fiber or fiber aggregate containing the lignocellulose derivative of the present invention is lightweight, has strength, and has a low linear thermal expansion coefficient, like plant fibers. The composition can exhibit thermoplasticity by including a fiber or a fiber assembly containing the lignocellulose derivative.

  Even if the composition includes fibers or fiber aggregates containing lignocellulose derivatives, the composition has a property (thermoplasticity) that softens when heated and becomes easy to mold, and becomes hard again when cooled, like a general-purpose plastic. Good processability can be expressed.

(7) Method for producing a composition comprising a lignocellulose derivative-containing fiber or fiber aggregate and a matrix material The composition of the present invention is a mixture of a fiber or fiber aggregate comprising the lignocellulose derivative of the present invention and the matrix material. Or by impregnating a fiber or fiber aggregate containing the lignocellulose derivative with a matrix material.

  Furthermore, a molded body can be produced by molding the composition. This is referred to as a molded body made of the composition.

  In the case of preparing a composition by mixing a fiber or fiber aggregate containing a lignocellulose derivative and a matrix material, the fiber or fiber aggregate containing lignocellulose and the matrix material are kneaded using a kneader or the like, When the fiber or fiber aggregate containing the inventive lignocellulose derivative and the matrix material are combined, the fibrillation of the fiber or fiber aggregate containing the inventive lignocellulose derivative proceeds during kneading, and the fibers and the matrix material are uniformly mixed. It is preferable because the composition can be easily obtained.

  The addition amount of the fiber or fiber aggregate containing lignocellulose is as described above with respect to the matrix material.

  When mixing the fiber or fiber assembly containing the lignocellulose derivative of the present invention and the matrix material, both components may be mixed without heating at room temperature, or may be mixed by heating. When heating, the mixing temperature can be adjusted according to the matrix material used.

  The mixing temperature is preferably about 40 ° C. or higher, more preferably about 50 ° C. or higher, and still more preferably about 60 ° C. or higher. By setting the mixing temperature to about 40 ° C. or higher, the fibers or fiber aggregates containing lignocellulose and the matrix material can be uniformly mixed.

  The mixing is preferably carried out by a kneading method using a kneader such as a bench roll, a Banbury mixer, a kneader, or a planetary mixer, a mixing method using a stirring blade, a mixing method using a revolution / rotation type stirrer, or the like.

  A composition can express thermoplasticity by including the fiber or fiber assembly containing the lignocellulose derivative of this invention. Similar to general-purpose plastics, the composition softens when heated and becomes easy to mold, and hardens again when cooled (thermoplasticity), and can exhibit good processability.

(8) Molded body (molded body) of a composition comprising a lignocellulose-containing fiber or fiber aggregate and a matrix material
A molded body (molded body) can be produced using the composition. This is referred to as a molded body made of the composition. Examples of the shape of the molded body include molded bodies having various shapes such as various shapes such as a film shape, a sheet shape, a plate shape, a pellet shape, a powder shape, and a three-dimensional structure. As the molding method, mold molding, injection molding, extrusion molding, hollow molding, foam molding and the like can be used.

  The molded product (molded product) can be used not only in the field of fiber reinforced plastics where a matrix molded product (molded product) containing plant fibers is used, but also in fields where thermoplasticity and mechanical strength (such as tensile strength) are required.

  Interior materials, exterior materials, structural materials, etc. for transportation equipment such as automobiles, trains, ships, airplanes, etc .; casings, structural materials, internal parts, etc. for electrical appliances such as personal computers, televisions, telephones, watches; mobile communications such as mobile phones Housings such as equipment, structural materials, internal parts, etc .; portable music playback equipment, video playback equipment, printing equipment, copying equipment, sports equipment, etc .; construction materials; office equipment such as stationery, etc. It can be used effectively as a container, container, and the like.

  The lignocellulose derivative of the present invention is characterized in that the lignin α-position of lignocellulose is modified. The lignocellulose derivative of the present invention is light, strong, and has a low coefficient of linear thermal expansion, as well as plant fibers, and can exhibit thermoplasticity.

  The lignocellulose derivative of the present invention itself has thermoplasticity, but even when mixed or impregnated with a matrix material, like a general-purpose plastic, it softens when heated and becomes easy to mold, and becomes hard again when cooled. It has (thermoplasticity) and can exhibit good processability.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The present invention is not limited to these examples.

  In Examples,% of component contents such as lignin, cellulose, hemicellulose and the like in pulp, lignocellulose, and modified lignocellulose indicates wt% unless otherwise specified. Further,% of the concentration of each component in the dispersion or solution indicates% by weight unless otherwise specified.

  In the examples, chemical functional group abbreviations, solvent abbreviations, and reagent abbreviations may be used. For example, Oct represents an octanoyl group and Ac represents an acetyl group.

(1) Method for preparing lignocellulose-containing material A fiber assembly (lignocellulose-containing material) containing the following lignocellulose was prepared.

(1-1) NGP
It is groundwood pulp derived from conifers. The lignin content is about 30% by weight, and the solid content (solid content / total weight) is about 19.8% by weight. The average fiber diameter is 29.0 μm, and the average fiber length is about 0.67 mm.

(1-2) LTMP
It is a thermomechanical pulp derived from hardwood. The lignin content is about 17.5% by weight, and the solid content (solid content / total weight) is about 79.4% by weight. The average fiber diameter is 29.2 μm, and the average fiber length is about 1.5 mm.

(1-3) BM-NCTMP
Water was added to chemical thermomechanical pulp derived from conifers (NCTMP, lignin content: 27% by weight) to prepare a pulp slurry having a solid content of 1.0% by weight. This pulp slurry was defibrated twice using a bead mill manufactured by Imex Corporation under the following conditions.

Defibration condition beads: Zirconia beads (diameter: 1mm)
Bead filling rate: 70%
Rotation speed: 2000rpm
Discharge rate: 600mL / min
The obtained fiber assembly containing lignocellulose is referred to as “fiber obtained by defibrating chemical thermomechanical pulp derived from conifers with a bead mill (BM-NCTMP)”.
The average fiber diameter of BM-NCTMP was about 20.8 μm, and the average fiber length was about 0.39 mm. The solid content ratio (solid content weight / total weight) was about 10.3% by weight.

(1-4) BM-NGP
Water was added to ground pulp from conifers (NGP, lignin content: 30% by weight) to prepare a pulp slurry having a solid content of 1.0% by weight. The pulp slurry was defibrated using a bead mill manufactured by Imex Co., Ltd. under the same conditions as in (1-3) above.

  The obtained fiber aggregate containing lignocellulose is referred to as “fiber obtained by defibrating groundwood pulp derived from conifers with a bead mill (BM-NGP)”. The average fiber diameter of BM-NGP was about 20.1 μm, and the average fiber length was about 0.28 mm. The solid content ratio (solid content weight / total weight) was about 17.5% by weight.

(2) Method for measuring lignocellulose-containing material
(2-1) Method for Quantifying Content of Each Component Lignin, cellulose and hemicellulose contained in a fiber assembly containing lignocellulose were quantified by the following method.

(i) Lignin determination method (Klarson method)
Glass fiber filter paper (GA55) was dried in an oven at 105 ° C. until it reached a constant weight, allowed to cool in a desiccator, and then weighed. Lignocellulose (sample of about 0.2 g) that had been completely dried at 105 ° C. was precisely weighed and placed in a 50 mL beaker. 3 mL of 72% concentrated sulfuric acid was added, and the mixture was left in warm water at 30 ° C. for 1 hour while being appropriately crushed with a glass rod so that the contents were uniform.

  Next, 84 g of distilled water was added to the contents, and quantitatively transferred to an Erlenmeyer flask, followed by reaction at 120 ° C. for 1 hour in an autoclave. After standing to cool, the contents were filtered through a glass fiber filter paper and washed with 200 mL of distilled water. Dry and weigh until constant weight in 105 ° C oven.

(ii) Determination method of cellulose and hemicellulose (sugar analysis)
The lignocellulose-containing material was placed in an oven desiccator and dried at 50 ° C. for 3 hours while reducing the pressure with a vacuum pump. About 30 mg of the dried sample was precisely weighed and placed in a pressure test tube, and then 200 μL of fucose (0.1 g / mL) was added as an internal standard. Using a pipette, 0.3 mL of 72% concentrated sulfuric acid was added, and the mixture was pushed evenly with a glass rod and reacted in a water bath at 30 ° C. for 1 hour.

  After 1 hour, 8.4 mL of distilled water was added, and the mixture was reacted in an autoclave at 120 ° C. for 1 hour. After allowing to cool, ultrapure water was added and diluted appropriately. The diluted solution was subjected to ion chromatographic analysis manufactured by Thermo Fisher Scientific, and the sugar component contained in the sample was analyzed.

(2-2) Measurement Method of Cellulose Fiber Diameter and Fiber Length Measurement was performed using a Kajaani fiber length measuring device manufactured by Metso.

(3) Structure analysis of lignocellulosic lignin α-position and method for measuring and determining the degree of modification
(3-1) Structural analysis by nuclear magnetic resonance (NMR) spectroscopy Model used: Bruker 800 MHz NMR device Previous method (Kim, H. and Ralph, K., Org. Biomol. Chem., 2010, 576 -591), a measurement sample was prepared. HSQC-NMR measurement was performed on the prepared sample. Actually, the sample (200 mg) is vacuum-dried overnight, then using a ball mill (Fritch planetary ball mill P-6, container 12 mL, zirconia), 50 balls (ball diameter 5 mm, zirconia) The sample was crushed. As the pulverization conditions, the operation of pulverization for 20 minutes and cooling for 10 minutes was repeated 5 times.

  The obtained ground sample (60 mg) was added to an NMR sample tube, and a mixed solution (0.5 mL) of DMSO-d / Pyridine-d (= 4/1) was added thereto to swell the sample. This was subjected to HSQC-NMR measurement, and structural analysis was performed from the obtained HSQC-NMR spectrum.

  When the lignin α position in the lignocellulose (raw material) is modified, a unique signal based on the modified group appears.

  For example, when the lignin α-position of lignocellulose is modified with an acetoxy group, the signal of Hα / Cα = 4.9 / 71.8 ppm that was present in the raw material decreased, and the new Hα / based on acetyloxy group was reduced to 6.1 / 74.7 ppm. Cα signal appears.

  On the other hand, when the lignin α position of lignocellulose is modified with, for example, an ethoxy group, a signal appears in the vicinity of 4.5 / 80 ppm.

(3-2) Confirmation of hydroxyl group modification by infrared (IR) absorption spectrum and determination method of degree of modification Model used: Fourier transform infrared spectrophotometer (FT-IR) manufactured by METTLER TOLEDO
When the lignin α-position in lignocellulose is modified with an acyloxy group, a characteristic absorption peak based on the stretching vibration of acyloxy C═O appears near 1730 cm ⁻¹ . Calculate the area from 1686cm ^-1 of the IR spectrum to 1778cm ^-1, it was calculated the following equation (calibration curve) than lignin α-position of the degree of modification (DSarufa).

DSα = 0.0113x-0.0122
x = (area from 1686cm ^-1 to 1778cm ^-1 after α-position modification)
- (area of from 1686cm ^-1 to 1778cm ^-1 before the α position modification)
The above equation (calibration curve), the lignin α-position of the ester group were quantified by hydrolysis was determined from the area value of from 1686cm ^-1 to 1778cm ^-1 in this value and the FT-IR spectrum.

(For details, see (i) to (iii) below)
(i) The solvent contained in the sample modified with the deesterified acyloxy group was replaced with tertiary butanol, pre-frozen with liquid nitrogen, and dried with a freeze dryer. The sample after freeze-drying was further dried at 50 ° C. for 2 hours using a vacuum dryer containing diphosphorus pentoxide.

  200 mg of a dry sample was weighed out, and 15 mL of ethanol and 10 mL of 0.5N sodium hydroxide aqueous solution were added using a whole pipette, respectively, and stirred for 30 minutes in a 70 ° C. water bath. Thereafter, the mixture was stirred at room temperature for 2 days.

(ii) Back titration By titrating the above solution after deesterification with 0.2N aqueous hydrochloric acid, the amount of sodium hydroxide consumed in the deesterification was calculated, and the amount of the characteristic group introduced (acyl) The amount of modification of the lignin α-position (DSα) was determined according to the following formula.

DSα = (A × F) / (W− (A × F)) × (M / F)
W: Dry weight of sample after esterification (g)
A: Amount of sodium hydroxide consumed in deesterification reaction (mol)
M: Average chemical formula amount of lignocellulose repeating unit
F: Chemical formula amount of the characteristic group introduced
M (average molecular weight of lignocellulose) was determined by the following formula.

M = 162 x (x / 100) + 162 x (y / 100) + 196 x (z / 100)
The numerical values of x, y, z and 162, 196 in the above formula have the following meanings.

162: Chemical formula amount of glucose repeating unit in cellulose x: Cellulose content (wt%) in raw material (lignocellulose)
162: Chemical formula amount of repeating unit of polysaccharide in hemicellulose (Hemicellulose is composed of various monosaccharide constituent units, but most of the chemical formula quantity of this constituent unit is the same as that of glucose)
y: Hemicellulose content (wt%) in raw material (lignocellulose)
196: Lignin repeating unit [1- (3-methoxy-4oxyphenyl) -1,3-propanediol. This corresponds to the partial structure of the chemical formula of R ₁ = R ₂ = H: 2- (2-methoxyphenoxy) -1- (3-methoxy-4oxyphenyl) -1,3-propanediol) in FIG. ] Chemical formula amount
z: Lignin content (wt%) in raw material (lignocellulose)

The (iii) DSα obtained in calculating back titration of the calibration curve was plotted with respect to the area from 1686cm ^-1 in FT-IR spectra to 1778cm ^-1, was calculated calibration curve.

(iv) Measurement of acylation degree of hemicellulose hydroxyl group and cellulose hydroxyl group (hereinafter also referred to as “DS _OH ”, “hydroxyl group substitution degree” or “hydroxyl modification degree” ) in double-modified lignocellulose derivative In the present invention, lignin α When α-modified lignocellulose whose position is modified with an acyloxy group is subjected to a normal acylation reaction, the hydroxyl group present in cellulose and hemicellulose in the α-modified lignocellulose derivative is acylated, and double-modified lignocellulose is converted into can get.

In this case, in the IR absorption spectrum, a characteristic absorption peak based on the C = O stretching vibration of the newly generated acyl group also appears in the vicinity of 1730 cm ^-1 and is based on the C = O stretching vibration of the acyloxy group at the lignin α-position. It overlaps with the characteristic absorption peak. That is, the absorption peak near 1730 cm ⁻¹ becomes high.

Therefore, the hydroxyl group modification degree (DS _OH ) can be determined from the following equation (calibration curve).

DS _OH = 0.0113x-0.0122
x = (area from 1686cm ^-1 to 1778cm ^-1 after hydroxyl groups modified)
- (area from 1686cm ^-1 to 1778cm ^-1 after α-position modification)
The total modification degree (DS _total , lignin α-position modification degree and sugar chain hydroxyl group modification degree) can be determined by the following equation.

DS _total = DSα + DS _OH
(4) Thermal Stability Test of α-Modified Lignocellulose Derivative Fiber Model: TGAQ50 apparatus manufactured by TA Instruments Co., Ltd. A dry sample (about 5.0 mg) was subjected to TGA measurement by the following method. The sample was measured in the range of 110 ° C. to 600 ° C. (temperature increase rate 10 ° C./min) under a nitrogen atmosphere (gas flow rate 100 mL / min). Sample weight loss and derivative curves were obtained.

  A 1% weight reduction temperature (1% loss temperature) when the weight at 120 ° C. was 100% by weight was calculated from the weight reduction curve, and a peak top temperature (peak top temperature) was calculated from the differential curve.

(5) Appearance evaluation of hot pressed products
(5-1) Preparation of Hot-Pressed Molded Body A molded body is obtained by compressing the fiber aggregate containing the lignocellulose derivative (lignocellulose derivative-containing material), and the appearance of the molded body is evaluated according to the following criteria. It was.

(5-2) Transparency (adhesion)
The evaluation criteria for transparency are as follows.

(Double-circle): The whole hot press molding obtained is transparent.
○: There is a part that is not partially adhered.
X: Not closely attached.

(5-3) Coloring evaluation The evaluation criteria for the colorability are as follows.

  Those having a transparency evaluation of x are not evaluated or colored.

(6) Physical property evaluation of hot-pressed compacts
(6-1) Linear thermal expansion coefficient The hot-pressed product was cut into a sample having a length of 35 mm and a width of about 5 mm using a cutter. The sample was set in a thermomechanical analyzer EXSTER TMA / SS6100 manufactured by SII Nanotechnology, and dried in a nitrogen atmosphere at 120 ° C. for 30 minutes, and then rapidly cooled to 10 ° C.

  Next, the temperature was raised to 130 ° C. at 5 ° C./min, and measurement was performed in a tensile mode. The average coefficient of linear expansion from 20 ° C to 100 ° C was defined as the coefficient of linear thermal expansion (CTE).

(6-2) Strength test (bending strength)
The hot-pressed product was cut into a length of 30 mm and a width of 5 mm using a cutter. Using an electromechanical universal testing machine (Instron 3365 Twin Column Desktop Testing System), a three-point bending test was performed at a distance between supporting points of 20 mm and a bending speed of 5 mm / min.

(6-3) Storage elastic modulus The hot-press molded product was cut into a length of 35 mm and a width of 5 mm using a cutter. Measurement was performed in a tensile mode using a dynamic viscoelasticity measuring apparatus (EXSTER DMS6100 manufactured by SII Nanotechnology). The storage elastic modulus (E ′) at 25 ° C. was measured under the conditions of a span of 20 mm, a frequency sin wave of 1 Hz, a temperature range of 20 ° C. to 300 ° C., and a heating rate of 2 ° C./min.

(7) Examples
Example 1a: α-position-modified lignocellulose derivative (method a: chlorite)
Example 1a-1
Implementation in which an acyloxy group was introduced using a chlorite at the α-position of the phenylpropane unit constituting the lignin of the lignocellulose-containing material (fiber aggregate containing lignocellulose) (that is, the lignin α-position of lignocellulose) It is an example.

  In a 300 mL glass container, put 48.6 g of hydrous BM-NCTMP (5 g of dry weight), add 118.1 g of acetic acid (saturated fatty acid into which acyloxy groups are introduced), and add solid content (absolute dry weight equivalent of BM-NCTMP). The concentration was adjusted to 3% by weight.

  Next, 0.293 g of sodium chlorite (0.47 equivalent to the total amount of hydroxyl groups (mol) of lignin contained in lignocellulose) was added to this sample, and the mixture was stirred at 80 ° C. for 15 hours to be reacted. After the reaction, the sample was washed successively with ethanol and water to obtain a fiber assembly containing a lignocellulose derivative having an acyloxy group (acetyloxy group) introduced at the α-position of the phenylpropane unit constituting lignin. The fiber assembly containing this lignocellulose derivative is hydrous.

  Thus, a fiber assembly (absolutely dry weight 5.0 g) containing the α-position-modified lignocellulose derivative could be obtained. The α-position modification degree (DSα) of this modified lignocellulose was 0.20.

Examples 1a-2 to 1a-11
As shown in Table 2, a sample having a solid content concentration (raw material concentration in terms of absolute dry weight) of 5 wt% was prepared using lignocellulose-containing material, carboxylic acid and water or NMP.

  An α-modified lignocellulose derivative was prepared in the same manner as in Example 1a-1 under the reaction conditions shown in Table 2 (reagent blending amount, reaction time, reaction temperature, etc.). Table 2 shows the α-position modification degree (DSα) of the α-position-modified lignocellulose derivative.

Explanation of Table 2 * 1: Add an excess amount of acetic acid so that the solid content concentration is 3% by weight * 2: Add 0.1 equivalent to the total amount of hydroxyl groups (mol) of lignin contained in lignocellulose * 3: Add 10 equivalents to the total hydroxyl content (mol) of lignin contained in lignocellulose * 4: Add 5 equivalents to the total hydroxyl content (mol) of lignin contained in lignocellulose * 5: In lignocellulose 0.47 equivalent added to the total hydroxyl content (mol) of lignin contained * 6: 2.0 equivalent added to the total hydroxyl content (mol) of lignin contained in lignocellulose * 7: lignin contained in lignocellulose Added 20 equivalents to the total amount of hydroxyl groups (mol) * 8: N-methylpyrrolidone (NMP) was used as a solvent instead of water.

Example 1b: α-modified lignocellulose (Method b: reaction in the presence of Lewis acid)
Example 1b-1
This is an example in which an acyloxy group is introduced into the α-position of the phenylpropane unit constituting the lignin of the lignocellulose-containing material (fiber aggregate containing lignocellulose) using a Lewis acid.

Lyophilized NGP (100 mg) was suspended in acetic acid (20 mL, saturated fatty acid introducing an acyloxy group). BF ₃ -Et ₂ O (10 μL) was added to this suspension and stirred at room temperature for one week. Thereafter, the sample was subjected to suction filtration and washed to obtain an α-position-modified lignocellulose derivative (α-position acetyloxy NGP, 98.mg) of the present invention in which the lignin α-position was modified with an acetyloxy group.

  FIG. 4 shows the HSQC-NMR spectrum of the used raw material (NGP), and FIG. 5 shows the HSQC-NMR spectrum of the lignocellulose derivative of the present invention in which the α-position is modified with an acetyloxy group.

  In this α-modified lignocellulose derivative of the present invention, the signal of Hα / Cα = 4.9 / 71.8 ppm (see FIG. 4) that originally existed in the raw material decreased, and it became a new acetyloxy group at 6.1 / 74.7 ppm. Based on Hα / Cα signal appeared (see FIG. 5). This confirmed the modification of the lignin to the α-position.

Example 1b-2
Lyophilized NGP (100 mg) was suspended in propionic acid (20 mL). BF ₃ -Et ₂ O (10 μL) was added to this suspension and stirred at room temperature for one week. Thereafter, the sample was suction filtered and washed to obtain a lignocellulose derivative (αpropionyloxy NGP 96.0 mg) of the present invention in which the lignin α-position was modified with a propionyloxy group.

Example 1b-3
Lyophilized NGP (100 mg) was suspended in chloroform (20 mL). Phenoxyacetic acid (454.2 mg) was added to this suspension, and BF ₃ -Et ₂ O (10 μL) was further added to initiate the reaction. The sample was stirred at room temperature for one week, filtered by suction, and washed to obtain the α-modified lignocellulose derivative of the present invention (NGP (95.0 mg) having a phenoxyacetyloxy group at the lignin α-position).

Example 1b-4
Using a Lewis acid at the α-position of the phenylpropane unit constituting the lignin of the lignocellulose-containing material (fiber aggregate containing lignocellulose: NGP) (that is, lignin α-position of lignocellulose), a methoxy group (of methyl alcohol) This is an example in which a residue obtained by removing a hydrogen atom from a chemical formula is introduced.

Lyophilized NGP (201.5 mg) was added to methanol (10 mL) and stirred. 100 μL of BF ₃ -Et ₂ O was added to the suspension, and the reaction was started at room temperature. 42 and 90.5 hours after the start of the reaction, 100 μL of BF ₃ -Et ₂ O was added. 0.25 mL of the reaction suspension was taken every 17, 39, 61.5, 87.5, 160, and 184 hours after the start of the reaction, filtered, washed with ethanol, and dried. A portion of the α-methoxylated NGP (5 mg) was taken and subjected to TGA analysis, and the progress of the reaction was followed by measuring the 1% weight loss temperature. After 216 hours, NGP (150.8 mg) containing the α-methoxylignocellulose derivative of the present invention was obtained by filtration, washing with methanol, and drying.

Example 1b-5
This is an example in which an ethoxy group (residue obtained by removing a hydrogen atom from the chemical formula of ethyl alcohol) is introduced into a lignocellulose α-position of a lignocellulose-containing material (fiber aggregate containing lignocellulose) using a Lewis acid.

Lyophilized NGP (206.5 mg) was added to ethanol (40 mL) and stirred. 20 μL of BF ₃ —Et ₂ O was added to the suspension, and the reaction was started at room temperature. 8 days after the start of the reaction, the reaction suspension was filtered, washed with ethanol, and dried. Then, an NGP containing a lignocellulose derivative having an ethoxy group at the lignin α-position of lignocellulose (an α-ethoxylignocellulose derivative of the present invention) was obtained.

  The HSQC-NMR spectrum of the α-ethoxylignocellulose derivative of the present invention is shown in FIG.

  In the α-ethoxylignocellulose derivative of the present invention, a signal of Hα / Cα based on an ethoxy group newly appeared around 4.5 / 80 ppm (see FIG. 6). This confirmed the modification to the lignin α-position. A signal appeared around 4.5 / 80 ppm. This is consistent with the model compound data.

Example 1b-6
Lyophilized NGP (57.9 mg) was added to dioxane (2 mL) and stirred. Dodecanethiol (1 mL) was added to the suspension and stirred. Thereafter, 80 μL of BF ₃ -Et ₂ O was added, and the reaction was started at 50 ° C. Three hours after the start of the reaction, ethanol was added to the reaction suspension to stop the reaction, followed by filtration, washing with ethanol and drying. Then, NGP (57.5 mg) containing a lignocellulose derivative having a dodecylthio group at the lignin α-position of lignocellulose was obtained.

In the FT-IR spectrum of the α-dodecylthioether derivative of the present invention, the peak intensities at 2924 cm ⁻¹ and 2852 cm ⁻¹ increased, confirming the introduction of a long chain alkyl group. Furthermore, from the results of elemental analysis, the introduction of thiol was also confirmed from the fact that C: 49.91%, H: 7.91%, N: 0.33%, S: 1.20%, and S were introduced.

Example 1b-7
Lyophilized NGP (60.0 mg) was added to methyl glycolate (2 mL) and stirred. 10 μL of BF ₃ -Et ₂ O was added to the suspension, and the reaction was started at 40 ° C. 20 hours after the start of the reaction, ethanol was added to the reaction suspension to stop the reaction, followed by filtration, ethanol washing and drying, and a residue obtained by removing a hydrogen atom from the chemical formula of methyl glycolate at the lignin α position of lignocellulose. A lignocellulose derivative into which was introduced was obtained (63 mg).

Example 1b-8
Lyophilized NGP (113.1 mg) was added to dioxane (4 mL) and stirred. Tetrahydrofurfuryl alcohol (2 mL) was added to the suspension and stirred. Thereafter, 160 μL of BF ₃ —Et ₂ O was added, and the reaction was started at 50 ° C. Three hours after the start of the reaction, ethanol was added to the reaction suspension to stop the reaction, followed by filtration, washing with ethanol and drying. Then, NGP (107.2 mg) containing a lignocellulose derivative having a tetrahydrofurfuryl ether group (tetrahydrofurfuryloxy group) at the lignin α-position of lignocellulose was obtained.

Since a shoulder peak was observed at 871 cm ⁻¹ in the FT-IR spectrum of the lignocellulose derivative of the present invention, introduction of a tetrahydrofurfuryl ether group (tetrahydrofurfuryloxy group) could be confirmed.

Example 1b-9
200 g of isopropyl alcohol (IPA) was added to NGP (2000 mg) and stirred. The sample was then suction filtered. This operation was repeated three times, and the sample was dehydrated by solvent replacement.

Then IPA (64.7 mL) was added and stirred. 0.33 mL of BF ₃ -Et ₂ O was added to the suspension, and the reaction was started at 40 ° C. After 20 hours from the start of the reaction, ethanol was added to the reaction suspension to stop the reaction, followed by filtration, ethanol washing and drying, and a residue obtained by removing a hydrogen atom from the chemical formula of isopropyl alcohol at the lignin α position of lignocellulose. The introduced lignocellulose derivative was obtained (2084 mg).

Example 1b-10
To NGP (5000 mg), 500 g of isopropyl alcohol (IPA) was added and stirred. The sample was then suction filtered. This operation was repeated three times, and the sample was dehydrated by solvent replacement.

Then, IPA (166.7 mL) was added and stirred. 0.33 mL of BF ₃ -Et ₂ O was added to the suspension, and the reaction was started at 40 ° C. After 20 hours from the start of the reaction, ethanol was added to the reaction suspension to stop the reaction, followed by filtration, ethanol washing and drying, and a residue obtained by removing a hydrogen atom from the chemical formula of isopropyl alcohol at the lignin α position of lignocellulose. The introduced lignocellulose derivative was obtained (5720 mg).

Example 1b-11
Lyophilized NGP (4000 mg) was added to dodecanol (160 mL) and stirred. BF ₃ -Et ₂ O (3.0 mL) was added to the suspension, and the reaction was started at 40 ° C. After 20 hours from the start of the reaction, ethanol was added to the reaction suspension to stop the reaction, filtration, ethanol washing, drying, and introduction of a residue obtained by removing hydrogen atoms from the chemical formula of dodecanol at the lignin α position of lignocellulose. A lignocellulose derivative was obtained (4840 mg).

Example 1b-12
To NGP (5000 mg), 500 g of ethanol was added and stirred. The sample was then suction filtered. This operation was repeated three times, and the sample was dehydrated by solvent replacement.

Thereafter, ethanol (205.1 mL) was added and stirred. 0.83 mL of BF ₃ -Et ₂ O was added to the suspension, and the reaction was started at 40 ° C. 20 hours after the start of the reaction, the reaction suspension was filtered, washed with ethanol, and dried to obtain a lignocellulose derivative in which a residue obtained by removing a hydrogen atom from the chemical formula of ethanol was introduced at the lignin α-position of lignocellulose (5310). mg).

Comparative Example 1b
Comparative Example 1b-1
Lyophilized NGP (200 mg) was added to anhydrous NMP (50 mL) and stirred overnight. Pyridine (309 μL, 3.839 mmol) and acetyl chloride (227 μL, 3.199 mmol) were added to the suspension to initiate the reaction. Ten minutes after the start of the reaction, ethanol was added to the reaction suspension to stop the reaction. This sample was subjected to suction filtration and ethanol washing to obtain NGP (189.5 mg) in which the hydroxyl group in the lignocellulose of NGP was acetylated. The obtained acetylated NGP was subjected to TGA analysis.

  The difference between the example and the comparative example is as follows. In Examples, it was confirmed by structural analysis by HSQC-NMR spectrum that the lignin selectively reacted at the α-position (benzyl position). On the other hand, in the comparative example, it confirmed that hydroxyl groups other than the polysaccharide hydroxyl group in lignocellulose and the lignin alpha-position (benzyl position) in lignocellulose reacted preferentially and were acetylated.

  Table 3 shows the test results of Example 1b and Comparative Example 1b, such as TGA analysis results.

  Although not shown in this table, the 1% weight loss temperature (1% loss temperature) of the raw material NGP was 209 ° C. This shows that the 1% weight loss temperature (1% loss temperature) increases when the lignin α-position of lignocellulose is modified. That is, when the lignin α-position is modified, the temperature at which thermal decomposition starts increases, indicating that the thermal stability of lignocellulose is improved.

Example 2a: Modification of hydroxyl group of sugar chain of α-modified lignocellulose derivative (produced by method a) (production of lignocellulose double-modified product)
Example 2a-1
In Example 1a-1, an acyloxy group was introduced into the α-position of the phenylpropane unit constituting the lignin of the lignocellulose-containing material using chlorite.

  In the lignocellulose-containing material containing the α-modified lignocellulose derivative, a hydroxyl group present in at least one of cellulose and hemicellulose contained in the α-position modified lignocellulose derivative (that is, a sugar chain hydroxyl group in the α-modified lignocellulose derivative) Is an example of octanoylation.

  350 g of N-methylpyrrolidone (NMP) was added to 4 g (absolutely dry weight) of a lignocellulose derivative having an acyloxy group at the lignin α-position (Example 1a-1) and stirred. The sample was then suction filtered. This operation was repeated three times, and the sample was dehydrated by solvent replacement.

  The dehydrated sample was placed in a 300 mL glass container, NMP was added, and the solid content concentration was adjusted to 3% by weight. Next, 1.67 g of pyridine (amount equivalent to 0.33 equivalent to the total hydroxyl amount (mol)) and 3.11 g of octanoyl chloride (amount equivalent to 0.3 equivalent to the total hydroxyl amount (mol)) were added to this sample. The mixture was stirred at 50 ° C. for 2 hours to be reacted.

After the reaction, the sample was washed successively with acetone, ethanol and water, and 4.35 g of a product in which the α-position was modified with an acyloxy group and the sugar chain was octanoylated (ie, lignocellulose double-modified product of the present invention) Absolutely dry weight) was obtained. This lignocellulose double-modified product had a hydroxyl group substitution degree (DS _OH ), that is, a degree of octanoylation of 0.19.

Examples 2a-2 to 2a-14
An acylation reaction of lignocellulose having an acyloxy group at the α-position was carried out in the same manner as in Example 2a-1 under the reaction conditions shown in Table 4 (reagent blending amount, reaction time, reaction temperature, etc.). Table 4 shows the degree of hydroxyl group substitution after the reaction.

Comparative Examples 2a-1 to 2a-4
Instead of lignocellulose having an acyloxy group at the α-position, a lignocellulose-containing material (a fiber assembly containing lignocellulose not modified at the α-position) was used.

  An acylation reaction of the lignocellulose-containing material was performed in the same manner as in Example 2a-1 under the reaction conditions (reagent blending amount, reaction time, reaction temperature, etc.) shown in Table 4. Table 4 shows the degree of hydroxyl group substitution after the reaction.

Description of Table 4 * 1: 0.33 equivalent added to total hydroxyl content (mol) * 2: 1.65 equivalent added to total hydroxyl content (mol) * 3: 1.5 equivalent added to total hydroxyl content (mol) * 4: 0.3 equivalent added to the total hydroxyl content (mol)

Example 2b: Modification of hydroxyl group of sugar chain of α-modified lignocellulose (produced by method b)
(Production of the lignocellulose double-modified product of the present invention)
Example 2b-1
In Example 1b-1, an acyloxy group was introduced into the α-position of the phenylpropane unit constituting the lignin of the lignocellulose-containing material using a Lewis acid.

  In the lignocellulose-containing material containing the α-modified lignocellulose derivative, the hydroxyl group present in at least one of cellulose and hemicellulose contained in the α-modified lignocellulose derivative (that is, the sugar chain hydroxyl group in the α-modified lignocellulose derivative) ) Is an acetylated example.

  73.5 mg of NGP (DSα = 0.26) having an acyloxy group at the lignin α-position prepared in Example 1b-1 was dispersed in anhydrous NMP (35 mL) overnight. Next, pyridine (860 μL, 10.7 mmol) and acetyl chloride (630 μL, 8.89 mmol) were added to the suspension to initiate the reaction.

One hour after the start of the reaction, ethanol was added dropwise to the reaction suspension to stop the reaction. By filtering this sample with suction and washing with ethanol, the lignin α-position in NGP was modified with an acyloxy group, and the sugar chain hydroxyl group in the lignin α-modified product was acetylated (hydroxyl substitution degree DS _OH = 0.79). NGP obtained, that is, a lignocellulose double modified product (68.0 mg) of the present invention was obtained.

The sum (DS _total ) of lignin α-position modification degree (DSα) 0.26 and hydroxyl group substitution degree (DS _OH ) 0.79 is 1.05. The obtained lignocellulose double modified product of the present invention was subjected to TGA analysis.

  The results of TGA analysis are summarized in Table 5.

Example 2b-2
130 g of N-methylpyrrolidone (NMP) was added to 1.3 g (absolute dry weight) of a lignocellulose derivative having an acyloxy group at the α-position of lignin (Example 1b-9) and stirred. The sample was then suction filtered. This operation was repeated three times, and the sample was dehydrated by solvent replacement.

  The dehydrated sample was placed in a 100 mL glass container, NMP was added, and the solid content concentration was adjusted to 3% by weight. Next, 2.94 g of potassium carbonate (amount equivalent to 1.1 equivalents to the total amount of hydroxyl groups (mol)) and 1.83 ml of acetic anhydride (amount corresponding to 1.0 equivalents to the total amount of hydroxyl groups (mol)) were added to this sample. The mixture was stirred at 80 ° C. for 20 hours to be reacted.

After the reaction, the sample was washed successively with acetone, ethanol and water, and 1.7 g of a product in which the α-position was modified with an acyloxy group and the sugar chain was acetylated (ie, lignocellulose double-modified product of the present invention) Absolutely dry weight) was obtained. This lignocellulose double-modified product had a hydroxyl group substitution degree (DS _OH ), that is, a degree of acetylation of 1.1.

The sum of the lignin α-position modification degree (DSα) 0.14 and the hydroxyl group substitution degree (DS _OH ) 1.1 ((DS _total )) is 1.24. The obtained lignocellulose double-modified product of the present invention was subjected to TGA analysis. The results of TGA analysis are summarized in Table 5.
Example 2b-3
300 g of N-methylpyrrolidone (NMP) was added to 3.0 g (absolute dry weight) of a lignocellulose derivative having an acyloxy group at the lignin α-position (Example 1b-10) and stirred. The sample was then suction filtered. This operation was repeated three times, and the sample was dehydrated by solvent replacement.

  The dehydrated sample was placed in a 200 mL glass container, NMP was added, and the solid content concentration was adjusted to 3% by weight. Next, 4.35 g of potassium carbonate (amount corresponding to 0.77 equivalent to the total hydroxyl amount (mol)) and 2.7 ml of acetic anhydride (amount corresponding to 0.7 equivalent to the total hydroxyl amount (mol)) were added to this sample. The mixture was stirred at 80 ° C. for 20 hours to be reacted. After the reaction, the sample was washed successively with acetone, ethanol and water, and 3.7 g of a product in which the α-position was modified with an acyloxy group and the sugar chain was acetylated (ie, lignocellulose double-modified product of the present invention) Absolutely dry weight) was obtained.

This lignocellulose double-modified product had a hydroxyl group substitution degree (DS _OH ), that is, a degree of acetylation of 1.0. The sum (DS _total ) of lignin α-position modification degree (DSα) 0.43 and hydroxyl group substitution degree (DS _OH ) 1.0 is 1.43.

  The obtained lignocellulose double modified product of the present invention was subjected to TGA analysis. The results of TGA analysis are summarized in Table 5.

Comparative Example 2b
Comparative Example 2b-1
The thermal stability of the lignocellulose double-modified product of Example 2-1 was compared with NGP prepared by ordinary acylation reaction. Acetylated NGP having the same degree of modification per total hydroxyl group (Total Ds) as that of Example 2b-1 was adjusted as follows.

  Lyophilized NGP (100 mg) was added to anhydrous NMP (50 mL) and stirred overnight. Pyridine (916 μL, 7.583 mmol) and acetyl chloride (449 μL, 6.319 mmol) were added to the suspension to initiate the reaction. Six hours after the start of the reaction, ethanol was added to the reaction suspension to stop the reaction. The sample was suction filtered and washed with ethanol to obtain acetylated NGP. The obtained Ac-modified GP was subjected to TGA analysis and HSQC-NMR analysis.

  One of the differences between Example 2b-1 and Comparative Example 2b-1 is the degree of acetylation of the hydroxyl groups at the α-position of both lignins. In Example 2b-1, acetylation proceeds at most α-position hydroxyl groups.

  On the other hand, in Comparative Example 2b-1, priority is given to acetylation of the hydroxyl groups other than the lignin α-position, and the hydroxyl groups present in the sugar chains of cellulose and hemicellulose, over the α-position hydroxyl group of lignin. In Comparative Example 2b-1, the lignin α-position hydroxyl group remains unreacted.

  For these reasons, the products of Example 2b-1 and Comparative Example 2b-1 are different.

  The product of Example 2b-1 has a 1% weight loss temperature (1% loss temperature) and peak top temperature determined from thermogravimetric analysis (TGA) higher than those of the product of Comparative Example 2b-1. Excellent thermal stability.

Example 3: Hot-pressed product of acylated product of a-position-modified lignocellulose derivative (lignocellulose double-modified product)
Example 3-1
In Example 1a-1, the α-position (lignin α-position) of the phenylpropane unit constituting the lignin in the lignocellulose-containing material was modified with an acyloxy group using chlorite.

  In Example 2a-1, the hydroxyl group present in at least one of cellulose and hemicellulose (that is, the sugar chain hydroxyl group in the α-position-modified lignocellulose derivative) contained in the α-position-modified lignocellulose derivative was octanoylated, An inventive lignocellulose double modified product was obtained (Example 2a-1). The lignocellulose double-modified product was hot-press molded as follows to obtain a hot-press molded product.

  Ethanol was added to 1.5 g (absolutely dry weight) of the lignocellulose double-modified product of Example 2a-1, and the mixture was stirred with a mixer for 30 seconds to adjust the solid content concentration to 1% by weight. Subsequently, this sample was subjected to suction filtration using No. 4 filter paper to obtain a circular sample having a radius of 3.8 cm.

  Using a compression molding machine (NF-37, manufactured by Shindo Metal Industries Co., Ltd.), the circular sample was compressed at room temperature at 3 MPa for about 1 minute and then dried in an oven at 40 ° C. The dried sample is sandwiched between 5 mm and 200 mm square metal plates coated with a release agent, pre-heated by using a compression molding machine for 8 minutes at 170 ° C, and then pre-heated, followed by hot pressing at 50 MPa for 10 minutes. Went. After 10 minutes, the heater power supply was turned off and cooling water was poured to cool to 50 ° C. or lower, and the produced hot-pressed product was taken out.

  Table 6 shows the appearance evaluation and physical property evaluation of the above-mentioned hot-press molded body.

Examples 3-2 to 3-15
In the same operation as in Example 3-1, the lignocellulose double-modified product described in Examples 2a-2 to 2a-13, Examples 2b-2 and 2b-3 was converted into the above Example 3-1. Hot pressing was performed under the conditions shown in Table 6 in the same manner. Table 6 shows the appearance and physical properties of the obtained hot-pressed product.

Comparative Examples 3-1 to 3-6
Instead of the lignocellulose double-modified product, the lignocellulose derivative of Comparative Examples 2a-1 to 2a-4 (with no modification at the α-position of lignin and a material comprising a derivative of acylated hydroxyl group in cellulose and hemicellulose) In the same manner as in Example 3-1, hot pressing was performed at the molding temperature shown in Table 6. Appearance evaluation and physical property evaluation of the obtained hot pressing molded article were also shown in Table 6.

  As represented by Comparative Examples 3-1 to 3-6, when a material composed of a lignocellulose derivative in which the lignin α-position was not modified was used, it had adhesion (transparency) at the molding temperature described in the Examples. A hot-press molded product could not be obtained.

  As represented by Examples 3-1 to 3-15, when a material comprising the lignocellulose double-modified product of the present invention is used, the thermoplasticity of the material is improved, and the low linear thermal expansion coefficient is suppressed. A hot-pressed product could be obtained. The thermoplasticity could be controlled by the type of functional group introduced into the lignin α-position of lignocellulose or the amount of functional group introduced.

  The lignocellulose derivative of the present invention is characterized by having a characteristic group (modifying group) at the lignin α-position (α-position of the phenylpropane unit constituting the lignin), and is light in weight and strong in the same manner as plant fibers. It has a low linear thermal expansion coefficient and can exhibit thermoplasticity.

  The lignocellulose derivative of the present invention, particularly the lignocellulose double-modified product of the present invention has a property (thermoplasticity) that softens when heated and becomes easy to mold, and becomes hard again when cooled (thermoplasticity), similar to general-purpose plastics. Can exhibit excellent processability.

Description of Table 6 * 1: The component ratio was calculated from the content of components (lignin, cellulose, hemicellulose) in the raw materials used and Total DS (degree of α-position modification + hydroxyl group substitution) listed in Table 4. .

Example 4: Resin composition containing acylated product (lignocellulose double-modified product) of α-position-modified lignocellulose derivative and matrix material, and molded product thereof
Example 4-1 Preparation of lignocellulose double-modified product In the same manner as in Example 2a-1, a lignocellulose double-modified product in which the α-position is modified with an acetyloxy group and the hydroxyl group of a sugar chain is modified with a myristoyl group is prepared. This water-washed product (water suspension) was obtained.

When this lignocellulose double-modified product was dried and the degree of modification was measured, the lignin α-position modification degree (DSα) was 0.20 (modified with an acetyloxy group), and the sugar chain hydroxyl group modification degree (DS _OH ) was 0.57 ( Modified with a myristoyl group).

Example 4-2
Nylon 6 (PA6), which is one of the matrix materials, is added to the aqueous suspension of the above lignocellulose double-modified product and mixed with Trimix (Inoue Seisakusho Co., Ltd.). The mixture was dried with stirring under reduced pressure. The obtained mixture was kneaded and granulated under the following conditions to obtain a resin composition containing the lignocellulose derivative of the present invention and a matrix material.

  Lignocellulose derivative content in this composition (content in terms of unmodified lignocellulose is 10% by mass).

・ Kneading equipment: "TWX-15 type" manufactured by Technobel
・ Kneading conditions: Temperature = 215 ° C

Production of resin composition molded body of the present invention The resin composition obtained above was injection molded under the following injection molding conditions to obtain a dumbbell-shaped resin molded body (strength test specimen, thickness 1 mm).

・ Injection molding machine: NP7 model made by Nissei Plastics
・ Molding conditions: Molding temperature = 220 ℃

Strength Test Using the electromechanical universal testing machine (Instron), the elastic modulus and tensile strength of the test piece obtained were measured at a test speed of 1.5 mm / min (load cell 5 kN).

  At that time, the distance between fulcrums was 4.5 cm.

  The target test piece (PA6 compact) was also prepared in the same manner, and its elastic modulus and tensile strength were measured.

  The measurement results were as follows.

The molded product of the present invention: tensile elastic modulus 2.5 GPa, tensile strength 59 MPa
Target PA6 compact: Tensile modulus 1.7GPa, Tensile strength 42MPa
The molded product containing the lignocellulosic derivative of the present invention showed a value about 1.5 times in terms of tensile modulus and about 1.4 times in terms of tensile strength, compared to a PA6 model.

Claims (12)

A chemically modified lignocellulose derivative comprising:
Α position of phenylpropane unit constituting lignin contained in lignocellulose,
General formula (1): R ¹ COO- (1)
An acyloxy group represented by
General formula (2): R ² O- (2)
And an oxy group represented by the general formula (3): R ³ S- (3)
A lignocellulose derivative modified with at least one characteristic group selected from the group consisting of thio groups represented by the formula: [In the formulas (1) to (3), R ^{1 to} R ³ are the same or different; An alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkidienyl group, a cycloalkenyl group, an alktrienyl group, an alkynyl group, an aryl group, a heteroaryl group, an aralkyl group, which may have a substituent , A heteroarylalkyl group, a heterocyclyl group, a heterocyclylalkyl group or a hydrogen atom (provided that R ² and R ³ are not a hydrogen atom or an ethynyl group)]. R ^{1 to} R ³ in the formulas (1) to (3) are the same or different, and each may have a substituent, each having a C1-C17 alkyl group, a C4-C8 cycloalkyl group, C2 -C17 alkenyl group, C2-C8 alkynyl group (where R ² and R ³ are not ethynyl groups, respectively), C4-C8 cycloalkenyl group, C4-C17 alkidienyl group, C4-C8 cycloalkyl A chidienyl group, a C6-C17 alkyltrienyl group, a lower alkyl group-substituted aryl group, a pyridyl group, a lower alkyl group-substituted pyridyl group, a thienyl group, or a lower alkyl group-substituted thienyl group,
The lignocellulose derivative according to claim 1. The acyloxy group represented by the general formula (1) is formic acid, acetic acid, propionic acid, butyric acid, valeric acid, pivalic acid, hexanoic acid, heptanoic acid, octanoic acid, pelargonic acid, decanoic acid, undecylic acid, lauric acid, Saturated fatty acid selected from tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, margaric acid, stearic acid, nonadecylic acid and arachidic acid; selected from phenoxyacetic acid, 3-phenoxypropionic acid, 4-phenoxybutyric acid and 5-phenoxyvaleric acid Aromatic substituted saturated fatty acids; unsaturated carboxylic acids selected from acrylic acid and methacrylic acid; monounsaturated fatty acids selected from crotonic acid, myristoleic acid, palmitoleic acid, oleic acid and ricinoleic acid; sorbic acid, linoleic acid and eicosadiene Diunsaturated fatty acids selected from acids; linolenic acid, A triunsaturated fatty acid selected from norenic acid and eleostearic acid; a tetraunsaturated fatty acid selected from stearidonic acid and arachidonic acid; a pentaunsaturated fatty acid selected from boseopenaenoic acid and eicosapentaenoic acid; selected from docosahexaenoic acid and nisic acid Hexa-unsaturated fatty acids; from benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, salicylic acid, gallic acid (3,4,5-trihydroxybenzenecarboxylic acid), cinnamic acid (3-phenylprop-2-enoic acid) Aromatic carboxylic acid selected; dicarboxylic acid selected from oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid and maleic acid; glycine, β-alanine and ε-aminocaproic acid (6-aminohexanoic acid) An amino acid selected from: maleimide compound:
Phthalimide compounds:
A residue obtained by removing a hydrogen atom from a carboxy group of at least one compound selected from the group consisting of:
The oxy group represented by the general formula (2) is methanol, ethanol, a linear alcohol having 3 to 12 carbon atoms, isopropanol, isobutanol, cyclooxanol, allyl alcohol, benzyl alcohol, phenol, 4-methylphenol, Tetrahydrofurfuryl alcohol, a residue obtained by removing a hydrogen atom from the hydroxy group of at least one compound selected from the group consisting of glycolic acid lower alkyl esters,
The thio group represented by the general formula (3) is methanethiol, ethanethiol, linear alkanethiol having 3 to 12 carbon atoms, isopropanethiol, isobutanethiol, cyclooxanethiol, 2-propene-1-thiol , A residue obtained by removing a hydrogen atom from a thiol group of at least one compound selected from the group consisting of cyclohexanethiol, benzyl mercaptan, cyclohexanemethanethiol, and thiophenol.
The lignocellulose derivative according to claim 1. The hydroxyl group present in at least one of cellulose and hemicellulose contained in the lignocellulose derivative may have a substituent, saturated fatty acid, monounsaturated fatty acid, diunsaturated fatty acid, triunsaturated fatty acid, tetraunsaturated fatty acid. Saturated fatty acid, pentaunsaturated fatty acid, hexaunsaturated fatty acid, aromatic carboxylic acid, aromatic dicarboxylic acid, amino acid,
Maleimide compounds:
And phthalimide compounds:
Substituted with a residue obtained by removing a hydrogen atom from a carboxy group of at least one compound selected from the group consisting of:
The lignocellulose derivative according to any one of claims 1 to 3.   The fiber or fiber assembly containing the lignocellulose derivative in any one of Claims 1-4.   A fiber or fiber assembly comprising the lignocellulose derivative according to claim 5 which is microfibrillated.   A compression molded product of a fiber or a fiber assembly containing the lignocellulose derivative according to claim 5 or 6.   A composition comprising a fiber or a fiber assembly comprising the lignocellulose derivative according to claim 5 or 6 and a matrix material.   The molded object which consists of a composition of Claim 8. The α-position of the phenylpropane unit constituting lignin is
General formula (1): R ¹ COO- (1)
An acyloxy group represented by
General formula (2): R ² O- (2)
And an oxy group represented by the general formula (3): R ³ S- (3)
A method for producing a lignocellulose derivative modified with at least one characteristic group selected from the group consisting of thio groups represented by:
In the presence of chlorite or Lewis acid,
Lignocellulose and general formula (1 '): R ¹ COOH (1')
A carboxylic acid represented by
General formula (2 ′): R ² OH (2 ′)
And the alcohol represented by
General formula (3 '): R ³ SH (3')
A process comprising the step of reacting with at least one compound selected from the group consisting of thiols represented by the formula (1) to (3) and formulas (1 ′) to (3 ′) R ^{1 to} R ³ may be the same or different and each may have a substituent, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkidienyl group, a cycloalkydenyl group, an alktrienyl group A group, an alkynyl group, an aryl group, a heteroaryl group, an aralkyl group, a heteroarylalkyl group, a heterocyclyl group, a heterocyclylalkyl group, or a hydrogen atom (wherein R ² and R ³ are not a hydrogen atom or an ethynyl group)]. (A) The α-position of the phenylpropane unit constituting lignin is
General formula (1): R ¹ COO- (1)
An acyloxy group represented by
General formula (2): R ² O- (2)
And an oxy group represented by the general formula (3): R ³ S- (3)
Modified with at least one characteristic group selected from the group consisting of thio groups represented by:
(B) a hydroxyl group present in at least one of cellulose and hemicellulose,
General formula (1): R ¹ COO- (1)
A method for producing a lignocellulose derivative substituted with an acyloxy group represented by:
(a) in the presence of chlorite or Lewis acid,
Lignocellulose and general formula (1 '): R ¹ COOH (1')
A carboxylic acid represented by
General formula (2 ′): R ² OH (2 ′)
And the alcohol represented by
General formula (3 '): R ³ SH (3')
Is reacted with at least one compound selected from the group consisting of thiols, and the α-position of the phenylpropane unit constituting the lignin is an acyloxy group represented by the general formula (1), the general formula (2 A process for producing a lignocellulose derivative modified with at least one characteristic group selected from the group consisting of an oxy group represented by formula (3) and a thio group represented by the general formula (3), and
(b) Lignocellulose and general formula (1 '): R ¹ COOH (1')
The hydroxyl group present in at least one of cellulose and hemicellulose is substituted with the acyloxy group represented by the general formula (1) by reacting with the acid chloride or acid anhydride of the carboxylic acid represented by A production method comprising a step of producing a lignocellulose derivative [in the formulas (1) to (3) and the formulas (1 ′) to (3 ′), R ^{1 to} R ³ are the same or different; Each of them may have a substituent, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkidienyl group, a cycloalkenyl group, an alktrienyl group, an alkynyl group, an aryl group, a heteroaryl group, an aralkyl group. Group, heteroarylalkyl group, heterocyclyl group, heterocyclylalkyl group or a hydrogen atom (provided that R ² and R ³ are not a hydrogen atom or an ethynyl group)]. General formula (1 ′): R ¹ COOH (1 ′)
The carboxylic acid represented by may have a substituent, saturated fatty acid, monounsaturated fatty acid, diunsaturated fatty acid, triunsaturated fatty acid, tetraunsaturated fatty acid, pentaunsaturated fatty acid, hexaunsaturated fatty acid, Aromatic carboxylic acid, aromatic dicarboxylic acid, amino acid,
Maleimide compounds:
And phthalimide compounds:
Is at least one compound selected from the group consisting of:
The method for producing a lignocellulose derivative according to claim 11.