WO2011132745A1

WO2011132745A1 - Cellulose derivative, resin composition, molding material, molded body, method for producing molded body, and housing for electric/electronic device

Info

Publication number: WO2011132745A1
Application number: PCT/JP2011/059852
Authority: WO
Inventors: 橋本　真一; 上平　茂生
Original assignee: 富士フイルム株式会社
Priority date: 2010-04-22
Filing date: 2011-04-21
Publication date: 2011-10-27
Also published as: JP2011225786A

Abstract

Disclosed is a cellulose derivative that is suitable for molding processes and has excellent thermal plasticity and strength. Specifically disclosed is a cellulose derivative wherein hydrogen atoms of hydroxyl groups contained in the cellulose have at least one group substituted by (A)) and at least one group substituted by (B)), and the total molar degree of substitution for the -C_nH_2n-O- groups contained in the groups substituted by (A)) is 0.5 - 3.0. The number average molecular weight is 150,000 or greater. (A)) Group containing the structure represented by general formula (1) (B)) Acyl group: -CO-R_B (R_B represents a C_1-3 hydrocarbon group.) (In general formula (1), n represents 2 or 3, and R_A represents a C_1-3 hydrocarbon.)

Description

Cellulose derivative, resin composition, molding material, molded article, method for producing molded article, and casing for electrical and electronic equipment

The present invention relates to a novel cellulose derivative, a resin composition, a molding material, a molded body, a method for producing the molded body, and a casing for electric and electronic equipment.

Various materials are used for members constituting electrical and electronic devices such as copiers and printers in consideration of the characteristics and functions required of the members. For example, PC (Polycarbonate), ABS (Acrylonitrile-butadiene-styrene) resin, PC / ABS, etc. are generally used as a member (housing) that stores a drive machine for electrical and electronic equipment and protects the drive machine. In large amounts (Patent Document 1). These resins are produced by reacting compounds obtained from petroleum as a raw material.

By the way, fossil resources such as oil, coal, and natural gas are mainly composed of carbon that has been fixed in the ground for many years. When such fossil resources or products made from fossil resources are burned and carbon dioxide is released into the atmosphere, carbon that was originally not deep in the atmosphere but fixed deep in the ground Is rapidly released as carbon dioxide, and carbon dioxide in the atmosphere greatly increases, which causes global warming. Therefore, polymers such as ABS and PC made from petroleum, which is a fossil resource, have excellent characteristics as materials for electrical and electronic equipment, but are made from petroleum, which is a fossil resource. Therefore, it is desirable to reduce the amount used from the viewpoint of preventing global warming.

On the other hand, a plant-derived resin is originally produced by a photosynthesis reaction using carbon dioxide and water in the atmosphere as raw materials. Therefore, even if plant-derived resin is incinerated to generate carbon dioxide, the carbon dioxide is equivalent to carbon dioxide originally in the atmosphere, so the balance of carbon dioxide in the atmosphere is plus or minus zero After all, there is an idea that the total amount of CO _{2 in} the atmosphere is not increased. Based on this idea, plant-derived resins are referred to as so-called “carbon neutral” materials. The use of carbon-neutral materials in place of petroleum-derived resins is an urgent need to prevent global warming in recent years.

For this reason, in PC polymer, the method of reducing petroleum origin resources is proposed by using plant origin resources, such as starch, as some raw materials derived from petroleum (patent documents 2).
However, further improvements are required from the perspective of aiming for a more complete carbon neutral material.

Various cellulose derivatives have been proposed in various fields.
For example, Patent Document 3 describes a cellulose ether ester having a specific structure, and describes that an optical film is prepared by dissolving the cellulose ether ester in a solvent and applying it.
Patent Document 4 describes that a cellulose derivative having an acyl group having a large number of carbon atoms is obtained from hydroxyethyl cellulose and a specific polyoxyalkylene agent.
Patent Document 5 describes cellulose stearate ester and cellulose palmitate ester made of hydroxypropyl cellulose.
Patent Document 6 describes, as liquid crystal polymers, cellulose derivatives obtained from hydroxyethyl cellulose and butyric acid, and cellulose derivatives obtained from hydroxypropyl cellulose and iodobutane.

Japanese Unexamined Patent Publication No. 56-55425 Japanese Unexamined Patent Publication No. 2008-24919 Japanese Unexamined Patent Publication No. 2007-99876 Japanese Patent No. 3973904 Japanese Patent Laid-Open No. 5-255401 Japanese Unexamined Patent Publication No. 2002-275379

The inventors of the present invention focused on using cellulose as a carbon neutral resin. However, since cellulose generally does not have thermoplasticity, it is difficult to mold by heating or the like, and thus is not suitable for molding. Further, even if thermoplasticity can be imparted, there is a problem that strength such as impact resistance is greatly reduced.
For example, since the cellulose derivative described in Patent Document 3 has a low degree of polymerization and a low molecular weight, a molded article produced using the cellulose derivative is considered to be inferior in impact resistance.
The cellulose derivatives described in Patent Documents 4 and 5 are considered to be unsuitable for molding because they are in a rubbery state at room temperature because of the large number of acyl group carbon atoms.
The cellulose derivative described in Patent Document 6 exhibits liquid crystallinity, and such a liquid crystalline resin is described in a paper by Gray et al. (Macromolecules 1981, 14, 715-719). In general, the total molar substitution MS of the —C _n H _2n —O— group is considered to be larger than 4. As a result of studies by the present inventors, it has been clarified that a cellulose derivative having a total molar substitution MS of a —C _n H _2n —O— group greater than 4 is in a rubbery state at room temperature and is not suitable for molding processing. .

An object of the present invention is to provide a cellulose derivative having good thermoplasticity and strength and suitable for molding processing.

The present inventors pay attention to the molecular structure of cellulose, and by making the cellulose into a cellulose derivative having a specific structure, the present invention expresses good thermoplasticity, and a molded article produced from the cellulose derivative has excellent impact resistance. The present invention was completed.
That is, the said subject can be achieved by the following means.

[1]
The hydrogen atom of the hydroxyl group contained in cellulose
Having at least one group substituted in A) below and at least one group substituted in B) below,
The total molar substitution degree of the —C _n H _2n —O— group contained in the group substituted with A) is 0.5 or more and 3.0 or less,
A cellulose derivative having a number average molecular weight of 150,000 or more.
A) A group containing a structure represented by the following general formula (1) B) Acyl group: —CO—R _B (R _B represents a hydrocarbon group having 1 to 3 carbon atoms.)

(In the general formula (1), n represents 2 or 3, and R _A represents a hydrocarbon group having 1 to 3 carbon atoms.)

[2]
The cellulose derivative according to the above [1], wherein R _A and R _B are each independently a methyl group or an ethyl group.
[3]
The cellulose derivative according to [1] above, wherein R _A and R _B are methyl groups.
[4]
[1] to [3], wherein the total molar substitution degree of the —C _n H _2n —O— group contained in the group containing the structure represented by the general formula (1) is 0.5 or more and 2.5 or less. ] The cellulose derivative of any one of.
[5]
The total molar substitution degree of the —C _n H _2n —O— group contained in the group containing the structure represented by the general formula (1) is 1.0 or more and 2.0 or less, according to [4] above. Cellulose derivative.
[6]
The cellulose derivative according to any one of [1] to [5] above, wherein the number average molecular weight is 200,000 or more and 500,000 or less.
[7]
The cellulose derivative according to any one of [1] to [6], wherein the cellulose derivative is obtained by acylating hydroxyethylcellulose, hydroxypropylcellulose, or hydroxyethylhydroxypropylcellulose.
[8]
The cellulose derivative according to any one of the above [1] to [7], wherein the cellulose derivative substantially does not contain an alkoxy group.
[9]
The cellulose derivative according to any one of [1] to [8] above, wherein the cellulose derivative is non-liquid crystalline.
[10]
A resin composition comprising the cellulose derivative according to any one of [1] to [9] above.
[11]
A molding material comprising the cellulose derivative according to any one of [1] to [9] above or the resin composition according to [10] above.
[12]
A molded body obtained by molding the cellulose derivative according to any one of [1] to [9], the resin composition according to [10], or the molding material according to [11].
[13]
The method includes heating and molding the cellulose derivative according to any one of [1] to [9], the resin composition according to [10], or the molding material according to [11]. The manufacturing method of a molded object.
[14]
A housing for electrical and electronic equipment comprising the molded article according to [12] above.

Since the cellulose derivative of the present invention has excellent thermoplasticity, it can be formed into a molded body. In particular, the cellulose derivative of the present invention can be molded at a low temperature even if it is a high molecular weight product.
In addition, the molded body produced from the cellulose derivative of the present invention has good impact resistance, and is suitable as a component part for automobiles, home appliances, electrical and electronic equipment, mechanical parts, housing / building materials, etc. Can be used. Moreover, since it is a plant-derived resin, it can be replaced with a conventional petroleum-derived resin as a material that can contribute to the prevention of global warming.

Hereinafter, the present invention will be described in detail.
1. Cellulose derivative The cellulose derivative of the present invention comprises:
The hydrogen atom of the hydroxyl group contained in cellulose
Having at least one group substituted in A) below and at least one group substituted in B) below,
The total molar substitution degree of the —C _n H _2n —O— group contained in the group substituted with A) is 0.5 or more and 3.0 or less,
It is a cellulose derivative having a number average molecular weight of 150,000 or more.
A) A group containing a structure represented by the following general formula (1) B) Acyl group: —CO—R _B (R _B represents a hydrocarbon group having 1 to 3 carbon atoms.)

That is, the cellulose derivative in the present invention is a group in which at least a part of hydrogen atoms of a hydroxyl group contained in cellulose {(C ₆ H ₁₀ O ₅ ) _n } includes a structure represented by A) the general formula (1). And at least a part of hydrogen atoms of another hydroxyl group is substituted by the B) acyl group (—CO—R _B ).
More specifically, the cellulose derivative in the present invention has a repeating unit represented by the following general formula (2).

(In General Formula (2), R ² , R ³ and R ⁶ are each independently a hydrogen atom, A) a group containing the structure represented by General Formula (1), or B) an acyl group (—CO— R _B ). ^However, at least a portion of R 2, ^{R 3,} and ^{R 6} represents a group containing a structure represented by A) formula ^(1), R 2, at least part of ^{R 3,} and ^{R 6} B) Represents an acyl group (—CO—R _B ). )

As described above, the cellulose derivative of the present invention comprises A) a group in which at least part of the hydroxyl groups of the β-glucose ring includes a structure represented by the general formula (1), and B) an acyl group (—CO—R _B ). By being substituted by, it is possible to impart formability to the cellulose.
Furthermore, since cellulose is a completely plant-derived component, it is carbon neutral and can greatly reduce the burden on the environment.

The “cellulose” referred to in the present invention is a polymer compound in which a large number of glucoses are bonded by β-1,4-glycosidic bonds, and the carbon atoms at the 2nd, 3rd and 6th positions in the glucose ring of cellulose. Means that the hydroxyl group bonded to is unsubstituted. Further, “hydroxyl group contained in cellulose” refers to a hydroxyl group bonded to carbon atoms at the 2nd, 3rd and 6th positions in the glucose ring of cellulose.

The cellulose derivative only needs to contain A) a group containing the structure represented by the general formula (1) and B) an acyl group (—CO—R _B ) in any part of the cellulose derivative. These may be composed of repeating units, or may be composed of a plurality of types of repeating units. Further, the cellulose derivative does not need to contain a substituent of A) a group including the structure represented by the general formula (1) and B) an acyl group (—CO—R _B ) in one repeating unit. .
More specific embodiments include the following embodiments, for example.
⁽¹⁾ R 2, ^{R 3} and part of ^{R 6} is, A) a repeating unit by a group containing a structure represented by the general formula (1) is ^substituted, one R 2, ^{R 3} and ^{R 6} A cellulose derivative comprising a part _B ) a repeating unit substituted with an acyl group (—CO—R _B ).
(2) In one repeating unit, any one of R ² , R ^3, and R ⁶ is substituted with a group including the structure represented by A) the general formula (1), and any of R ² , R ^3, and R ⁶ B) A cellulose derivative composed of the same type of repeating unit substituted with an acyl group (—CO—R _B ) (that is, having the above-mentioned substituents A) and B) in one repeating unit.
(3) A cellulose derivative in which repeating units having different substitution positions and different types of substituents are bonded at random.
Further, a part of the cellulose derivative may contain an unsubstituted repeating unit (that is, a repeating unit in which R ² , R ³ and R ⁶ are all hydrogen atoms in the general formula (2)).

A) A group including the structure represented by the general formula (1) will be described. A) General formula (1) is a group containing an acyl group and an alkyleneoxy group.

In the general formula (1), R _A represents a hydrocarbon group having 1 to 3 carbon atoms. R _A may be either a straight chain or branched aliphatic group, and may have an unsaturated bond.
R _A is preferably an alkyl group having 1 to 3 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, and an isopropyl group. R _A is more preferably a methyl group or an ethyl group, and even more preferably a methyl group.

A) The group including the structure represented by the general formula (1) may include a plurality of alkyleneoxy groups or may include only one. More specifically, the group A) can be represented by the following general formula (1 ').

(In the general formula (1 ′), n represents 2 or 3, and R _A represents a hydrocarbon group having 1 to 3 carbon atoms. N ′ represents an integer of 1 or more.)

In the general formula (1 '), specific examples and preferred ranges of R _A are the same as R _A in the general formula (1).
The upper limit of n ′ is not particularly limited, and varies depending on the amount of alkyleneoxy group introduced, but is, for example, about 10, preferably 9 and more preferably 7.
The group containing the structure represented by A) general formula (1) of the cellulose derivative of the present invention may be one type or two or more types. For example, a group of A) containing only one alkyleneoxy group (a group in which n ′ is 1 in the above formula (1 ′)) and a group of A) containing two or more alkyleneoxy groups (the above formula) And a group in which n ′ is 2 or more in the general formula (1 ′) may be mixed and contained.
n is preferably 2.

B) The acyl group (—CO—R _B ) will be described.
B) In the acyl group (—CO—R _B ), R _B represents a hydrocarbon group having 1 to 3 carbon atoms. The R _B, can be applied the same as those mentioned in R _A in the general formula (1). The preferred range of R _B is the same as R _A.
The cellulose derivative of the present invention may have one or more B) acyl groups.

In the cellulose derivative, A) a group containing the structure represented by the general formula (1), and _B ) the substitution position of the acyl group (—CO—R _B ), and the number of each substituent per β-glucose ring unit ( The degree of substitution) is not particularly limited.

For example, A) Degree of substitution DSa of a group containing the structure represented by the general formula (1) (A in the repeating unit, A for hydroxyl groups at the 2nd, 3rd and 6th positions of the cellulose structure of the β-glucose ring) The number of groups including the structure represented by 1) is 0 <DSa, and more preferably 0.1 <DSa. Since the melting start temperature can be lowered when 0.1 <DSa, thermoforming can be performed more easily.

B) Degree of substitution DSb of the acyl group (—CO—R _B ) ( _B ) in the repeating unit, B) the number of hydroxyl groups at the 2nd, 3rd and 6th positions of the cellulose structure of the β-glucose ring). 1 <DSb is preferable, and 0.1 <DSb <2.0 is more preferable.
The sum DSa + DSb of the substitution degree DSa of the group including the structure represented by the general formula (1) and B) the substitution degree DSb of the acyl group is 1.5 <DSa + DSb ≦ 3.0, and 2.0 <DSa + DSb ≦ 3.0 is preferable, and 2.5 <DSa + DSb ≦ 3.0 is more preferable. By satisfying 2.5 <DSa + DSb ≦ 3.0, the melting start temperature can be lowered, and the hygroscopicity of the molded piece can be lowered.

In addition, the cellulose derivative may have an unsubstituted hydroxyl group. The hydrogen atom substitution degree DSh (ratio in which the hydroxyl groups at the 2-position, 3-position and 6-position in the polymerization unit are unsubstituted) can be preferably in the range of 0 to 1.5, more preferably 0 to 0. .6. By setting DSh to 0.6 or less, it is possible to improve the fluidity of the thermoforming material, or to suppress foaming due to water absorption of the thermoforming material during acceleration / molding of thermal decomposition.

The cellulose derivative preferably does not substantially contain an alkoxy group other than the —C _n H _2n —O— group in the group containing the structure represented by A) the general formula (1). The cellulose derivative of the present invention further improves the hydrophobicity by substantially not containing an alkoxy group other than the —C _n H _2n —O— group in the group containing the structure represented by the general formula (1). Can be made. This is because, for example, when an alkoxy group is included, a cellulose ether having an alkoxy group generally exhibits high hygroscopicity. Further, the alkoxy group does not have a hydroxyl group capable of easily introducing an acyl group which is a hydrophobic group. For these reasons, it is unsuitable for use as a molding material of the present invention because of its poor hydrophobicity.
Note that “substantially free of an alkoxy group other than the —C _n H _2n —O— group in the group containing the structure represented by the general formula (1)” means that the cellulose derivative in the present invention has the general formula ( 1) Including the case where the group including the structure represented by 1) does not contain an alkoxy group other than the —C _n H _2n —O— group, and also includes the case where the cellulose derivative in the present invention has a trace amount of an alkoxy group at the terminal hydroxyl group. It shall be. For example, the cellulose as the raw material may contain an alkoxy group, and the cellulose derivative using the above-described substituents A) and B) introduced therein may contain an alkoxy group. Is substantially not included ".
In this case, the preferred content of alkoxy groups, 0.1 in the degree of substitution DS _C alkoxy group, and more preferably 0.05 or less. The degree of substitution of the alkoxy group can be quantified by ¹ H-NMR.

In addition, the introduction amount of —C _n H _2n —O— group (also referred to as alkyleneoxy group) in the group containing the structure represented by the general formula (1) is the molar substitution degree (MS: per glucose residue). The number of moles of substituents introduced) (edited by Cellulose Society, Cellulose Dictionary P142). The total molar substitution degree MS of the alkyleneoxy group is 0.5 ≦ MS ≦ 3.0, preferably 0.5 ≦ MS ≦ 2.5, and 1.0 ≦ MS ≦ 2.0. Is more preferable. When MS is 0.5 or more and 3.0 or less, heat resistance, moldability and the like can be improved, and a cellulose derivative suitable for a thermoforming material can be obtained.
The cellulose derivative of the present invention is preferably non-liquid crystalline.

The type, degree of substitution, and MS (degree of molar substitution of alkyleneoxy group) of the cellulose derivative are determined by ¹ H-NMR using the method described in Cellulose Communication 6, 73-79 (1999). can do.

The molecular weight of the cellulose derivative in the present invention has a number average molecular weight (Mn) of 150,000 or more, preferably in the range of 150,000 to 1,000,000, more preferably in the range of 200,000 to 500,000, further 300,000 to 500,000. preferable. The mass average molecular weight (Mw) is preferably in the range of 500,000 to 10 million, and more preferably in the range of 1.5 to 6 million. By setting the average molecular weight within this range, it is possible to improve the moldability and mechanical strength of the molded body.

The molecular weight distribution (MWD) is preferably in the range of 1.1 to 15.0, more preferably in the range of 2.0 to 12.5. By setting the molecular weight distribution within this range, moldability and the like can be improved.
In the present invention, the number average molecular weight (Mn), mass average molecular weight (Mw) and molecular weight distribution (MWD) can be measured using gel permeation chromatography (GPC). Specifically, N-methylpyrrolidone is used as a solvent, a polystyrene gel is used, and the molecular weight can be determined using a conversion molecular weight calibration curve obtained in advance from a standard monodisperse polystyrene constituent curve.

In the present invention, the degree of polymerization of the cellulose derivative is preferably in the range of 500 to 2000, more preferably in the range of 750 to 1500, and still more preferably 1000 to 1400. When the number average molecular weight is 60,000, the degree of polymerization is 240, when the number average molecular weight is 120,000, the degree of polymerization is 310, and when the number average molecular weight is 450,000, the degree of polymerization is about 1300. By setting it as the polymerization degree of this range, the moldability of a molded object, mechanical strength, etc. can be improved.

2. Method for Producing Cellulose Derivative The method for producing a cellulose derivative in the present invention is not particularly limited, and the cellulose derivative of the present invention can be produced by using cellulose as a raw material and etherifying and esterifying cellulose. The raw material for cellulose is not limited, and examples thereof include cotton, linter, and pulp.
Preferred embodiments of the production method include, for example, hydroxyethyl cellulose having a hydroxyethyl group: —C ₂ H ₄ —OH or hydroxypropyl cellulose having a hydroxypropyl group: —C ₃ H ₆ —OH, or a hydroxyethyl group and a hydroxypropyl group It is performed by a method including a step of esterification (acylation) by reacting hydroxyethylhydroxypropylcellulose having an acid chloride or an acid anhydride.
As a method for reacting acid chloride, for example, the method described in Cellulose 10; 283-296, 2003 can be used.
Since this esterification occurs with respect to the hydroxyl group of hydroxyethyl group, hydroxypropyl group, and hydroxyl group of cellulose, when the reaction is carried out using a plurality of esterifying agents (acid anhydride, acid chloride), a plurality of types are used. The esterified hydroxyethyl, hydroxypropyl, and acyl groups are obtained.

Hydroxyethyl cellulose, hydroxylpropyl cellulose, and hydroxyethyl hydroxypropyl cellulose can be synthesized from cellulose by a conventional method, or commercially available ones may be used.
For example, referring to the description in JP 2008-534735 A, hydroxyethyl cellulose and hydroxypropyl cellulose can be synthesized from cellulose.
In addition, the commercially available product has a plurality of substitution degree types. For each substitution degree type, there is a viscosity grade indicated by a viscosity value of a 2% aqueous solution at 20 ° C., with a viscosity value of about 1 to 200,000. is there. In general, a high viscosity grade has a higher molecular weight (Mn, Mw) than a low viscosity grade. You may adjust the molecular weight of the cellulose derivative to produce | generate by changing the viscosity grade to be used. The viscosity of a raw material preferable for obtaining a high molecular weight body is a viscosity value of 5000 to 200,000. Examples of commercially available hydroxyethyl cellulose include trade name AX-15 (manufactured by Sumitomo Seika), trade names EP 850 and SP 900 (manufactured by Daicel Chemical Industries). Examples of commercially available hydroxypropyl cellulose include those under the trade names LDC-H (manufactured by Shin-Etsu Chemical Co., Ltd.) and Aldrich.

As the acid chloride, an acyl group contained in A) and a carboxylic acid chloride corresponding to B) an acyl group can be used. Examples of the carboxylic acid chloride include acetyl chloride, propionyl chloride, butyryl chloride, isobutyryl chloride and the like.

As the acid anhydride, for example, carboxylic acid anhydrides corresponding to the acyl group and B) acyl group contained in A) can be used. Examples of such carboxylic anhydrides include acetic anhydride, propionic anhydride, butyric anhydride, and the like.

An acid may be used as the catalyst. Preferred acids include, for example, sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid, perchloric acid, phosphoric acid, trifluoroacetic acid, trichloroacetic acid and the like. More preferred are sulfuric acid and methanesulfonic acid. Bisulfates may also be used, and examples include lithium bisulfate, sodium bisulfate, and potassium bisulfate. A solid acid catalyst may also be used. For example, a polymer solid acid catalyst such as an ion exchange resin, an inorganic oxide solid acid catalyst typified by zeolite, and a carbon type used in JP2009-67730A. A solid acid catalyst is mentioned. A Lewis acid catalyst may also be used, and examples thereof include titanic acid ester catalysts and zinc chloride used in US Pat. No. 2,976,277.

A base may be used as the catalyst. Examples thereof include pyridines, alkali metal salts of acetic acid such as sodium acetate, dimethylaminopyridine, and anilines.

There is also a reaction system in which the esterification reaction proceeds without using a catalyst. For example, a reaction system using N, N-dimethylacetamide as a solvent and acetyl chloride or propionyl chloride as an acetylating agent can be mentioned.

As the solvent, a general organic solvent can be used. Of these, carboxylic acids and carboxamide solvents are preferred. As the carboxylic acid, for example, a carboxylic acid corresponding to the acyl group contained in A) and the acyl group contained in B) can be used. When carboxylic acid is used, ethyl acetate or acetonitrile may be used in combination. Examples of the carboxamide-based solvent include those used in JP-T-10-5117129 and US Pat. No. 2,705,710, and examples thereof include N, N-dimethylacetamide. Further, dimethyl sulfoxide containing lithium chloride as used in JP-A-2003-41052 may be used. Further, a halogenated solvent may be used, preferably dichloromethane. Pyridine that can be used as a base may be used as a solvent. Further, as used in JP-A-9-157301, acid chloride used as an esterifying agent may be used as a solvent. *

Cellulose used as a raw material is made from biomass resources such as cotton linter and wood pulp. You may use what was made from biomass resources also about raw materials other than a cellulose etc. Examples thereof include acetic acid and acetic anhydride produced by fermentation from ethanol produced from cellulosic biomass or starch biomass.

As pre-treatment, as disclosed in Japanese Patent No. 2754066, acetic acid containing a carboxylic acid or a small amount of an acid catalyst may be added to the raw material cellulose derivative and mixed.

The raw material cellulose or the like may be dried before use to reduce the water content. Since the moisture content causes a side reaction that reacts with acetic anhydride, the amount of acetic anhydride to be used can be reduced by reducing the moisture content.

As disclosed in Japanese Patent No. 2754066, the rate of the esterification reaction may be controlled by adding the catalyst in portions, changing the addition rate, or combining them. The esterification reaction is a vigorous exothermic reaction, and since the reaction solution becomes highly viscous, it is effective when heat removal is difficult.

As disclosed in JP-A-60-139701, by reducing the pressure in the reaction system for the entire period of the esterification reaction or for a part of the period including the initial stage, the generated vapor is condensed and discharged to harm to the reaction system. The reaction product may be concentrated. In this method, heat can be removed by removing the reaction heat generated by the esterification reaction with the latent heat of evaporation of the volatile solvent.

The esterification reaction may be performed in multiple stages as disclosed in JP-T-2000-511588. For example, as a first step, cellulose is reacted with a first acetylating agent in the presence of a base catalyst, and then as a second step, it is reacted with a second acetylating agent in the presence of an acid catalyst.

If the temperature of the esterification reaction is high, the esterification reaction rate is accelerated and the reaction time can be shortened, but the molecular weight is likely to decrease due to the depolymerization reaction. If the temperature is low, the esterification reaction becomes slow. It is preferable to adjust the reaction temperature and time depending on the structure of the target cellulose derivative and the target molecular weight (Mn, Mw).

When performing the esterification reaction, as in International Publication No. 01/070820, the reaction may be performed by irradiating ultrasonic waves.

In the esterification reaction, as the reaction proceeds, the mixture in the reactor gradually exhibits a dope shape from the solid-liquid state, and the dope viscosity in the reaction system becomes very high. As described in Japanese Examined Patent Publication No. 2-5761, the dope viscosity is further increased in a method in which the gas phase component of the reaction system is distilled out of the reaction system and the esterification reaction is performed under reduced pressure conditions. When the dope viscosity becomes very high as described above, it is desirable to use a biaxial kneader as the esterification reactor. However, a general glass lined reaction kettle or the like should be used by reducing the dope viscosity by increasing the amount of carboxylic acid as a solvent or by using another organic solvent in combination to lower the concentration of the reaction solution. Can also

After the esterification step is completed, a base (usually in the form of an aqueous solution) or water (alcohol may be used) is added to decompose unreacted acetic anhydride to stop the reaction. When a base is added, the acid catalyst is neutralized, and when water is added, the acid catalyst is not neutralized. Generally, it is better to neutralize, but it is not necessary to neutralize. The case where it is better to neutralize is, for example, the case where the thermal stability of the synthesized polymer is lowered due to the influence of bound sulfuric acid bonded to the cellulose derivative. Further, as a method for reducing the amount of bound sulfuric acid, as disclosed in JP-A-2006-89574, the bound sulfuric acid is decomposed without neutralization at once by a method such as continuous addition of a base. A method of neutralizing step by step while maintaining easy liquidity can be employed. The neutralizing agent is not particularly limited as long as it is a base, but preferably includes an alkali metal compound and an alkaline earth metal compound. Specifically, sodium acetate, potassium acetate, calcium acetate, magnesium acetate, Calcium hydroxide, magnesium hydroxide and the like.

The method for separating the target cellulose derivative is not particularly limited, and for example, precipitation, filtration, washing, drying, extraction, concentration, column chromatography and the like can be used alone or in appropriate combination of two or more. From the viewpoints of properties and purification efficiency, a method of separating the cellulose derivative by precipitation (reprecipitation) operation is preferable. In the precipitation operation, the solution containing the cellulose derivative is mixed with the poor solvent, for example, the reaction solution containing the cellulose derivative is put into the poor solvent of the cellulose derivative, or the poor solvent is put into the solution containing the cellulose derivative. Is done.

The poor solvent for the target cellulose derivative may be a solvent having low solubility of the cellulose derivative, and examples thereof include dilute acetic acid, water, and alcohols. Preferably, it is dilute acetic acid or water.

The solid-liquid separation method of the obtained precipitate is not particularly limited, and methods such as filtration and sedimentation can be used. Filtration is preferred, and various dehydrators using decompression, pressurization, gravity, squeezing, centrifugation and the like can be used. For example, a vacuum dehydrator, a pressure dehydrator, a belt press, a centrifugal filtration dehydrator, a vibrating screen, a roller press, a belt screen, and the like can be given.

The separated precipitate often removes acetic acid, acid used as an acid catalyst, solvent, and free metal components by washing such as water. In particular, acetic acid and the acid used as the acid catalyst are preferably removed because they cause a decrease in the molecular weight of the resin during molding and a decrease in physical performance.

A neutralizing agent may be added during washing. The neutralizing agent is not particularly limited as long as it is a base, but preferably includes an alkali metal compound and an alkaline earth metal compound. Specifically, sodium acetate, potassium acetate, calcium acetate, magnesium acetate, Calcium hydroxide, magnesium hydroxide and the like. Further, as disclosed in JP-B-6-67961, a buffer solution may be used for washing.

The drying method is not particularly limited, and various dryers that perform drying under conditions such as air blowing and reduced pressure can be used.

Other specific manufacturing conditions can follow the usual method. For example, the method described in “Encyclopedia of Cellulose” pages 131 to 164 (Asakura Shoten, 2000) can be referred to.

3. Resin Composition, Molding Material, and Molded Article The resin composition of the present invention contains the cellulose derivative described above. Moreover, another additive can be contained as needed.
The content rate of the component contained in the resin composition of this invention is not specifically limited. Preferably, the cellulose derivative is contained in an amount of 75% by mass or more, more preferably 80% by mass or more, and further preferably 80 to 100% by mass.
In addition to the cellulose derivative of the present invention, the resin composition of the present invention may contain various additives such as a filler and a flame retardant as necessary.

The resin composition of the present invention may contain a filler (reinforcing material). By containing the filler, the mechanical properties of the formed article can be enhanced.

Usable fillers can be used. The shape of the filler may be any of fibrous, plate-like, granular, powdery and the like. Further, it may be inorganic or organic.
Specifically, as the inorganic filler, glass fiber, carbon fiber, graphite fiber, metal fiber, potassium titanate whisker, aluminum borate whisker, magnesium whisker, silicon whisker, wollastonite, sepiolite, slag fiber, zonolite, Elastadite, gypsum fiber, silica fiber, silica-alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber and boron fiber, and other inorganic fillers; glass flakes, non-swellable mica, carbon black, graphite, metal foil , Ceramic beads, talc, clay, mica, sericite, zeolite, bentonite, dolomite, kaolin, fine silicate, feldspar, potassium titanate, shirasu balloon, calcium carbonate, magnesium carbonate, barium sulfate, calcium oxide Beam, aluminum oxide, titanium oxide, magnesium oxide, aluminum silicate, silicon oxide, aluminum hydroxide, magnesium hydroxide, gypsum, novaculite, dawsonite, and a plate-like or granular inorganic fillers of clay or the like.

Organic fillers include synthetic fibers such as polyester fiber, nylon fiber, acrylic fiber, regenerated cellulose fiber, and acetate fiber, and natural fibers such as kenaf, ramie, cotton, jute, hemp, sisal, Manila hemp, flax, linen, silk, and wool. Examples thereof include fibrous organic fillers obtained from microcrystalline cellulose, sugar cane, wood pulp, paper waste, waste paper and the like, and granular organic fillers such as organic pigments.

When the resin composition contains a filler, the content thereof is not limited, but is usually 30 parts by mass or less, preferably 5 to 10 parts by mass with respect to 100 parts by mass of the cellulose derivative.

The resin composition of the present invention may contain a flame retardant. Thereby, the flame retarding effect such as reduction or suppression of the burning rate can be improved.
The flame retardant is not particularly limited, and a conventional flame retardant can be used. For example, brominated flame retardants, chlorine-based flame retardants, phosphorus-containing flame retardants, silicon-containing flame retardants, nitrogen compound-based flame retardants, inorganic flame retardants and the like can be mentioned. Among these, hydrogen halides are not generated by thermal decomposition during resin compounding or molding, and do not corrode processing machines or molds or deteriorate the working environment. Phosphorus-containing flame retardants and silicon-containing flame retardants are preferred because they are less likely to adversely affect the environment through the generation of harmful substances such as dioxins when they are diffused or decomposed.

The phosphorus-containing flame retardant is not particularly limited, and a commonly used one can be used. Examples thereof include organic phosphorus compounds such as phosphate esters, phosphate condensation esters, and polyphosphates.

Specific examples of phosphate esters include trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri (2-ethylhexyl) phosphate, tributoxyethyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, tris (isopropylphenyl) Phosphate, tris (phenylphenyl) phosphate, trinaphthyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, diphenyl (2-ethylhexyl) phosphate, di (isopropylphenyl) phenyl phosphate, monoisodecyl phosphate, 2-acryloyloxyethyl Acid phosphate, 2-methacryloyloxyethyl acid phosphate, diphenyl -2-acryloyloxyethyl phosphate, diphenyl-2-methacryloyloxyethyl phosphate, melamine phosphate, dimelamine phosphate, melamine pyrophosphate, triphenylphosphine oxide, tricresylphosphine oxide, diphenyl methanephosphonate, diethyl phenylphosphonate Can be mentioned.

Examples of the phosphoric acid condensed ester include resorcinol polyphenyl phosphate, resorcinol poly (di-2,6-xylyl) phosphate, bisphenol A polycresyl phosphate, hydroquinone poly (2,6-xylyl) phosphate, and condensates thereof. Aromatic phosphoric acid condensed ester and the like.

In addition, polyphosphates composed of salts of phosphoric acid, polyphosphoric acid and metals of Groups 1 to 14 of the periodic table, ammonia, aliphatic amines, and aromatic amines can also be mentioned. As typical salts of polyphosphates, lithium salts, sodium salts, calcium salts, barium salts, iron (II) salts, iron (III) salts, aluminum salts and the like as metal salts, methylamine salts as aliphatic amine salts, Examples include ethylamine salts, diethylamine salts, triethylamine salts, ethylenediamine salts, piperazine salts, and examples of aromatic amine salts include pyridine salts and triazines.

In addition to the above, halogen-containing phosphate esters such as trischloroethyl phosphate, trisdichloropropyl phosphate, tris (β-chloropropyl) phosphate), and structures in which a phosphorus atom and a nitrogen atom are connected by a double bond Phosphazene compounds having phosphoric acid and phosphoric ester amides.
These phosphorus-containing flame retardants may be used singly or in combination of two or more.

Examples of the silicon-containing flame retardant include an organic silicon compound having a two-dimensional or three-dimensional structure, polydimethylsiloxane, or a methyl group at a side chain or a terminal of polydimethylsiloxane, a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, Examples thereof include those substituted or modified with an aromatic hydrocarbon group, so-called silicone oils, or modified silicone oils.

Examples of the substituted or unsubstituted aliphatic hydrocarbon group and aromatic hydrocarbon group include an alkyl group, a cycloalkyl group, a phenyl group, a benzyl group, an amino group, an epoxy group, a polyether group, a carboxyl group, a mercapto group, Examples include a chloroalkyl group, an alkyl higher alcohol ester group, an alcohol group, an aralkyl group, a vinyl group, or a trifluoromethyl group.
These silicon-containing flame retardants may be used alone or in combination of two or more.

Examples of the flame retardant other than the phosphorus-containing flame retardant or the silicon-containing flame retardant include, for example, magnesium hydroxide, aluminum hydroxide, antimony trioxide, antimony pentoxide, sodium antimonate, zinc hydroxystannate, zinc stannate, Metastannic acid, tin oxide, tin oxide salt, zinc sulfate, zinc oxide, ferrous oxide, ferric oxide, stannous oxide, stannic oxide, zinc borate, ammonium borate, ammonium octamolybdate, tungsten Inorganic flame retardants such as acid metal salts, complex oxides of tungsten and metalloid, ammonium sulfamate, ammonium bromide, zirconium compounds, guanidine compounds, fluorine compounds, graphite, and swellable graphite can be used. . These other flame retardants may be used alone or in combination of two or more.

When the resin composition of the present invention contains a flame retardant, its content is not limited, but is usually 30 parts by mass or less, preferably 2 to 10 parts by mass with respect to 100 parts by mass of the cellulose derivative. By setting it as this range, impact resistance, brittleness, etc. can be improved, or generation | occurrence | production of pellet blocking can be suppressed.

The resin composition of the present invention is not limited to the cellulose derivatives, fillers and flame retardants described above, and may be used for the purpose of further improving various properties such as moldability and flame retardancy within a range not impairing the object of the present invention. Ingredients may be included.
Examples of other components include polymers other than the cellulose derivatives, plasticizers, stabilizers (antioxidants, UV absorbers, etc.), mold release agents (fatty acids, fatty acid metal salts, oxyfatty acids, fatty acid esters, aliphatic moieties. Saponified ester, paraffin, low molecular weight polyolefin, fatty acid amide, alkylene bis fatty acid amide, aliphatic ketone, fatty acid lower alcohol ester, fatty acid polyhydric alcohol ester, fatty acid polyglycol ester, modified silicone), antistatic agent, flame retardant aid, Examples include processing aids, anti-drip agents, antibacterial agents, and antifungal agents. Further, a coloring agent containing a dye or a pigment can be added.

As the polymer other than the cellulose derivative, any of a thermoplastic polymer and a thermosetting polymer can be used, but a thermoplastic polymer is preferable from the viewpoint of moldability. Specific examples of polymers other than cellulose derivatives include low density polyethylene, linear low density polyethylene, high density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-propylene-nonconjugated diene copolymer, ethylene-butene- 1 copolymer, polypropylene homopolymer, polypropylene copolymer (such as ethylene-propylene block copolymer), polyolefins such as polybutene-1 and poly-4-methylpentene-1, polybutylene terephthalate, polyethylene terephthalate and other aromatic polyesters, etc. Polyamide such as polyester, nylon 6, nylon 46, nylon 66, nylon 610, nylon 612, nylon 6T, nylon 12, etc., polystyrene, high impact polystyrene, polyacetate (Including homopolymers and copolymers), polyurethanes, aromatic and aliphatic polyketones, polyphenylene sulfide, polyether ether ketone, thermoplastic starch resins, polymethyl methacrylate and methacrylate-acrylate copolymers Acrylic resin, AS resin (acrylonitrile-styrene copolymer), ABS resin, AES resin (ethylene rubber reinforced AS resin), ACS resin (chlorinated polyethylene reinforced AS resin), ASA resin (acrylic rubber reinforced AS resin) ), Polyvinyl chloride, polyvinylidene chloride, vinyl ester resin, maleic anhydride-styrene copolymer, MS resin (methyl methacrylate-styrene copolymer), polycarbonate, polyarylate, polysulfone, polyethersulfone, phenoxy resin Thermoplastic polyimide such as polyphenylene ether, modified polyphenylene ether, polyetherimide, polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-ethylene copolymer, tetrafluoroethylene-perfluoroalkyl vinyl ether Fluoropolymers such as polymers, polychlorotrifluoroethylene, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene-perfluoroalkyl vinyl ether copolymers, cellulose acetate, polyvinyl alcohol, unsaturated polyesters, melamine resins, phenol resins, A urea resin, a polyimide, etc. can be mentioned. Various acrylic rubbers, ethylene-vinyl acetate copolymers, ethylene-acrylic acid copolymers and alkali metal salts thereof (so-called ionomers), ethylene-acrylic acid alkyl ester copolymers (for example, ethylene-ethyl acrylate copolymer) Copolymer, ethylene-butyl acrylate copolymer), diene rubber (for example, 1,4-polybutadiene, 1,2-polybutadiene, polyisoprene, polychloroprene), copolymer of diene and vinyl monomer (for example, Styrene-butadiene random copolymer, styrene-butadiene block copolymer, styrene-butadiene-styrene block copolymer, styrene-isoprene random copolymer, styrene-isoprene block copolymer, styrene-isoprene-styrene block copolymer Polymer, polybutadiene Styrene-grafted styrene, butadiene-acrylonitrile copolymer), polyisobutylene, copolymer of isobutylene and butadiene or isoprene, butyl rubber, natural rubber, thiocol rubber, polysulfide rubber, acrylic rubber, nitrile rubber, poly Examples include ether rubber, epichlorohydrin rubber, fluoro rubber, silicone rubber, and other thermoplastic elastomers such as polyurethane, polyester, and polyamide.

Furthermore, those having various degrees of crosslinking, those having various microstructures such as cis structure and trans structure, those having vinyl groups, those having various average particle diameters, core layers and the like A multi-layer structure polymer called a so-called core-shell rubber, which is composed of one or more shell layers to be covered and whose adjacent layers are composed of different types of polymers, can also be used, and further a core-shell rubber containing a silicone compound Can also be used.
These polymers may be used alone or in combination of two or more.

When the resin composition of the present invention contains a polymer other than the cellulose derivative, the content thereof is preferably 30 parts by mass or less, more preferably 2 to 10 parts by mass with respect to 100 parts by mass of the cellulose derivative.

The resin composition of the present invention may contain a plasticizer. Thereby, a flame retardance and a moldability can be improved further. As the plasticizer, those commonly used for polymer molding can be used. Examples thereof include polyester plasticizers, glycerin plasticizers, polycarboxylic acid ester plasticizers, polyalkylene glycol plasticizers, and epoxy plasticizers.

Specific examples of the polyester plasticizer include acid components such as adipic acid, sebacic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, rosin, propylene glycol, 1,3-butanediol, 1,4 -Polyesters composed of diol components such as butanediol, 1,6-hexanediol, ethylene glycol and diethylene glycol, and polyesters composed of hydroxycarboxylic acids such as polycaprolactone. These polyesters may be end-capped with a monofunctional carboxylic acid or monofunctional alcohol, or may be end-capped with an epoxy compound or the like.

Specific examples of the glycerin plasticizer include glycerin monoacetomonolaurate, glycerin diacetomonolaurate, glycerin monoacetomonostearate, glycerin diacetomonooleate, and glycerin monoacetomonomontanate.

Specific examples of polycarboxylic acid plasticizers include phthalates such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, diheptyl phthalate, dibenzyl phthalate, butyl benzyl phthalate, and trimellitic acid. Trimellitic acid esters such as tributyl, trioctyl trimellitic acid, trihexyl trimellitic acid, diisodecyl adipate, n-octyl-n-decyl adipate, methyl diglycol butyl diglycol adipate, benzyl methyl diglycol adipate, adipic acid Adipic acid esters such as benzylbutyl diglycol, citrate esters such as triethyl acetylcitrate and tributyl acetylcitrate, azelaic acid esters such as di-2-ethylhexyl azelate, sebashi Dibutyl, and include di-2-ethylhexyl sebacate and the like.

Specific examples of the polyalkylene glycol plasticizer include polyethylene glycol, polypropylene glycol, poly (ethylene oxide / propylene oxide) block and / or random copolymer, polytetramethylene glycol, ethylene oxide addition polymer of bisphenols, and bisphenols. And a polyalkylene glycol such as a propylene oxide addition polymer, a tetrahydrofuran addition polymer of bisphenol, or a terminal epoxy-modified compound thereof, a terminal ester-modified compound, a terminal ether-modified compound, and the like.

The epoxy plasticizer generally refers to an epoxy triglyceride composed of an alkyl epoxy stearate and soybean oil, but there are also so-called epoxy resins mainly made of bisphenol A and epichlorohydrin. Can be used.

Specific examples of other plasticizers include benzoate esters of aliphatic polyols such as neopentyl glycol dibenzoate, diethylene glycol dibenzoate, triethylene glycol di-2-ethylbutyrate, fatty acid amides such as stearamide, oleic acid Examples thereof include aliphatic carboxylic acid esters such as butyl, oxy acid esters such as methyl acetylricinoleate and butyl acetylricinoleate, pentaerythritol, and various sorbitols.

When the resin composition of the present invention contains a plasticizer, the content thereof is usually 5 parts by mass or less, preferably 0.005 to 5 parts by mass, more preferably 0.005 parts by mass with respect to 100 parts by mass of the cellulose derivative. 01 to 1 part by mass.

The molding material of the present invention contains the cellulose derivative or the resin composition.

The molded body of the present invention can be obtained by molding the cellulose derivative, the resin composition, or the molding material.
More specifically, it is obtained by a production method including a step of heating the cellulose derivative or the resin composition containing the cellulose derivative and various additives as necessary, and molding them by various molding methods.
Examples of the molding method include injection molding, extrusion molding, blow molding and the like.
The heating temperature is usually 160 to 300 ° C, preferably 180 to 260 ° C.

The use of the molded article of the present invention is not particularly limited. For example, interior or exterior parts of electric and electronic equipment (home appliances, OA / media related equipment, optical equipment, communication equipment, etc.), automobiles, mechanical parts And materials for housing and construction. Among these, from the viewpoint of having excellent heat resistance and impact resistance and low environmental impact, for example, exterior parts (especially casings) for electrical and electronic equipment such as copiers, printers, personal computers, and televisions. ) Can be suitably used.

Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to these examples.

<Synthesis Example 1: Synthesis of acetoxyethylacetylcellulose (C-1)>
In a 3 L three-necked flask equipped with a mechanical stirrer, thermometer, condenser, and dropping funnel, weigh 65 g of hydroxyethyl cellulose (trade name AX-15; manufactured by Sumitomo Seika), 2000 mL of N, N-dimethylacetamide, and add 1 at 110 ° C. Stir for hours. Thereafter, 250 mL of acetyl chloride was slowly added dropwise at room temperature to raise the temperature of the system to 80 ° C. After stirring for 2 hours, the temperature of the reaction system was cooled to room temperature. When the reaction solution was poured into 6 L of water with vigorous stirring, a white solid was precipitated. The white solid was filtered off by suction filtration and washed twice with a large amount of water. The obtained white solid was vacuum-dried at 80 ° C. for 6 hours to obtain the target cellulose derivative (C-1) (acetoxyethylacetylcellulose, the degree of substitution described in Table 1) as a white powder (72.1 g). ).

<Synthesis Example 2: Synthesis of acetoxypropylacetylcellulose (C-2)>
With reference to JP-A-2008-534735, cellulose ether was first obtained by the following method. That is, t-butyl alcohol (757 g), isopropanol (35.7 g), acetone (26.8 g), water (73.2 g), and crushed linter (99.2 g) were weighed into a 3 L beaker, and 1 at room temperature. Stir for hours. Thereafter, this suspension and a 50% aqueous sodium hydroxide solution (55.6 g) were added to a 2 L autoclave and stirred at room temperature for 45 minutes. Thereafter, the temperature was raised to 55 ° C., propylene oxide (124.6 g) was added and stirred for 2 hours, and then stirred at 95 ° C. for 2 hours. Following this, the reaction mixture was cooled to 40 ° C., neutralized with 60% aqueous nitric acid (56.0 g), and filtered through a Buchner funnel. The residue was washed with acetone and then dehydrated to obtain hydroxypropylcellulose as a solid (143 g).
A cellulose derivative (C-2) (acetoxypropylacetylcellulose) was obtained as a solid in the same manner except that the hydroxyethylcellulose of Synthesis Example 1 was replaced with the hydroxypropylcellulose (72.1 g).

<Synthesis Example 3: Synthesis of acetoxyethyl acetoxypropyl acetyl cellulose (C-3)>
Hydroxyethylhydroxypropylcellulose was obtained as a solid (124 g) in the same manner except that the propylene oxide of Synthesis Example 2 was changed to propylene oxide (62.3 g) and ethylene oxide (47.4 g).
A cellulose derivative (C-3) (acetoxyethylacetoxypropylacetylcellulose) was obtained as a solid (69.9 g) in the same manner except that the hydroxyethylcellulose of Synthesis Example 1 was replaced with the hydroxyethylhydroxypropylcellulose.

<Synthesis Example 4: Synthesis of propionyloxyethyl propionyl cellulose (C-4)>
The target cellulose derivative (C-4) (propionyloxyethylpropionylcellulose) was obtained as a white powder in the same manner except that the acetyl chloride in Synthesis Example 1 was changed to propionyl chloride (77.3 g).

<Synthesis Example 5: Synthesis of butanoyloxyethyl butanoyl cellulose (C-5)>
The target cellulose derivative (C-5) (butanoyloxyethylbutanoylcellulose) was obtained as a white powder in the same manner except that the acetyl chloride in Synthesis Example 1 was changed to butanoyl chloride (80.1 g). .

<Synthesis Example 6: Synthesis of acetoxyethylacetylcellulose (C-6)>
Hydroxyethyl cellulose was obtained as a solid (114 g) in the same manner except that the propylene oxide of Synthesis Example 2 was changed to ethylene oxide (42.2 g). The target cellulose derivative (C-6) (acetoxyethylacetylcellulose) was obtained as a solid (70.4 g) in the same manner except that the hydroxyethylcellulose of Synthesis Example 1 was changed to the hydroxyethylcellulose.

<Synthesis Example 7: Synthesis of acetoxyethyl acetyl cellulose (C-7)>
The target cellulose derivative (C-7) (acetoxyethylacetylcellulose) was obtained as a white powder in the same manner except that the hydroxyethyl cellulose of Synthesis Example 1 was changed to the trade name SP900 (manufactured by Daicel) (79.6 g). ).

<Synthesis Example 8: Synthesis of acetoxyethylacetylcellulose (C-8)>
The target cellulose derivative (C-8) (acetoxyethyl acetylcellulose) was obtained as a white powder in the same manner except that the hydroxyethyl cellulose of Synthesis Example 1 was changed to the trade name EP850 (manufactured by Daicel) (81.6 g ).

<Synthesis Example 9: Synthesis of acetoxyethyl acetyl cellulose (C-9)>
Hydroxyethyl cellulose was obtained as a solid (129 g) in the same manner except that the propylene oxide of Synthesis Example 2 was changed to ethylene oxide (96.5 g).
The target cellulose derivative (C-9) (acetoxyethylacetylcellulose) was obtained as a solid (68.4 g) in the same manner except that the hydroxyethylcellulose of Synthesis Example 1 was changed to the hydroxyethylcellulose.

<Synthesis Example 10: Synthesis of acetoxypropylacetylcellulose (R-1)>
Cellulose derivative (R-1) (acetoxypropylacetylcellulose) was treated with white powder in the same manner except that the hydroxyethylcellulose of Synthesis Example 1 was changed to hydroxypropylcellulose (trade name LDC-H (manufactured by Shin-Etsu Chemical Co., Ltd.)). (73.3 g).

<Synthesis Example 11: Synthesis of acetoxyethylacetylcellulose (R-2)>
Hydroxyethyl cellulose was obtained as a solid (143 g) in the same manner except that the propylene oxide of Synthesis Example 2 was changed to ethylene oxide (113.4 g).
A cellulose derivative (R-2) (acetoxyethylacetylcellulose) was obtained as a solid (69.0 g) in the same manner except that the hydroxyethylcellulose of Synthesis Example 1 was changed to the hydroxyethylcellulose.

<Synthesis Example 12: Synthesis of acetoxypropylacetylcellulose (R-3)>
A cellulose derivative (R-3) (acetoxypropylacetylcellulose) was obtained as a white solid in the same manner except that the hydroxyethylcellulose of Synthesis Example 1 was changed to hydroxypropylcellulose (product number 191906, manufactured by Aldrich) (76. 7g).

<Synthesis Example 13: Synthesis of acetoxyethylacetylcellulose (R-4)>
A cellulose derivative (R-4) (acetoxyethylacetylcellulose) was obtained as a white solid in the same manner except that the hydroxyethylcellulose of Synthesis Example 1 was changed to the trade name AL15 (manufactured by Sumitomo Seika) (74.2 g) .

<Synthesis Example 14: Synthesis of pentanoyloxyethyl pentanoyl cellulose (R-5)>
A cellulose derivative (R-5) (pentanoyloxyethyl pentanoyl cellulose) was obtained as a white solid in the same manner except that the acetyl chloride in Synthesis Example 1 was changed to pentanoyl chloride (84.1 g).

The cellulose derivatives obtained above were classified into Cellulose Communication 6, 73-79 (1999) with respect to the type and degree of substitution of functional groups substituted with cellulose, and MS (total molar substitution degree of alkyleneoxy groups). ) Was observed and determined by ¹ H-NMR using the method described in ¹ ).

<Measurement of molecular weight of cellulose derivative>
About the obtained cellulose derivative, the number average molecular weight (Mn) and the mass average molecular weight (Mw) were measured. These measuring methods are as follows.
[Molecular weight]
For the measurement of the number average molecular weight (Mn) and the mass average molecular weight (Mw), gel permeation chromatography (GPC) was used. Specifically, N-methylpyrrolidone was used as a solvent, a polystyrene gel was used, and a molecular weight calibration curve obtained in advance from a constituent curve of standard monodisperse polystyrene was used. As the GPC apparatus, HLC-8220 GPC (manufactured by Tosoh Corporation) was used.

Number average molecular weight (Mn), mass average molecular weight (Mw), A) DSa + DSb sum of substitution degree of acyl group and alkyleneoxy group and B) substitution degree of acyl group, substitution degree DSh of hydrogen atom, terminal hydroxyl group Table 1 summarizes the alkoxy substitution degree DSc and MS.

In the above table, “A) a group containing an acyl group and an alkyleneoxy group in cellulose derivatives (C-1), (C-6) to (C-9), (R-2), and (R-4)” All include a group represented by the following formula (1-1), and in the cellulose derivatives (C-2), (R-1), and (R-3), all are represented by the following formula (1-2). The cellulose derivative (C-3) contains a group represented by the following general formula (1-3), and the cellulose derivative (C-4) represents a group represented by the following formula (1-4). A group represented by the following formula (1-5) in the cellulose derivative (C-5), and a group represented by the following formula (1-6) in the cellulose derivative (R-5). including.

(In the general formula (1-3), R represents H or CH ₃ group.)

<Observation of liquid crystallinity of cellulose derivative>
The cellulose derivatives (C-1) to (C-9) and (R-1) to (R-5) obtained above are taken on a slide glass, and the cellulose is observed by texture observation with a polarizing microscope (Nikon ECLIPISE LV100POL). The liquid crystallinity of the derivative was confirmed. A METTLER (FP82HT manufactured by METTLER TOLEDO) was used for heating. The results are shown in Table 2.

From Table 2, the cellulose derivative (R-3) having a large MS of 5.0 exhibited liquid crystallinity, and a coloration effect peculiar to cholesteric liquid crystals was observed from room temperature to 100 ° C., whereas a cellulose derivative having a small MS It was found that (C-1) to (C-9), (R-1) to (R-2), (R-4), and (R-5) did not show liquid crystallinity even when the temperature was changed. .

<Preparation of a molded body made of a cellulose derivative>
[Test specimen preparation]
Cellulose derivatives (C-1) to (C-9), (R-1) to (R-5), (R-6) obtained above (Daicel EP850: hydroxyethylcellulose, MS: 1.7) , (R-7) (manufactured by Sumitomo Seika: Hydroxyethyl cellulose, MS: 2.2) is supplied to a micro-molding machine (Imoto Seisakusho, semi-automatic injection molding machine) and the cylinder temperature is 140-230 ° C., injection An attempt was made to mold a 4 × 10 × 80 mm multipurpose test piece (impact test piece) at a pressure of 1.5 kgf / cm ² .

<Measurement of physical properties of test piece>
About the thing from which the molded piece was obtained, Charpy impact strength was measured in accordance with the following method. The results are shown in Table 3.
[Charpy impact strength]
In accordance with ISO 179, a multi-purpose test piece molded by injection molding is formed with a notch having an incident angle of 45 ± 0.5 ° and a tip of 0.25 ± 0.05 mm, 23 ° C. ± 2 ° C., 50% ± 5% After standing at RH for 48 hours or more, the impact strength was measured edgewise with a Charpy impact tester (manufactured by Toyo Seiki Seisakusho).

It was found that the cellulose derivative (R-3) having MS having a liquid crystallinity of 5.0 and the cellulose derivative (R-5) having a pentanoyl group are almost rubbery at room temperature and are not suitable for molding applications. Further, although the cellulose derivative (R-2) having an MS of 3.2 could be molded, the Charpy impact strength of the molded body was low. In addition, although the cellulose derivative (R-4) having a number average molecular weight of 92,000 was able to be molded, the Charpy impact strength was lower than that of the molded body of the example. On the other hand, it was found that cellulose derivative (R-1) having MS of 0.3 has insufficient thermoplasticity and decomposes without melting even when the temperature is raised, and is not suitable for molding applications. In addition, hydroxyethyl cellulose (R-6) and (R-7) having MS of 1.7 and 2.2, respectively, decomposed without melting even when the temperature was raised, whereas hydroxyethyl cellulose with the same MS The acetylated cellulose derivatives (C-1) and (C-7) could be molded at relatively low temperatures of 175 ° C. and 160 ° C., respectively. It was also found that the Charpy impact strength of (C-1) was higher than that of the cellulose derivative (R-4) having the same MS and a low molecular weight.

Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.
This application is based on a Japanese patent application filed on Apr. 22, 2010 (Japanese Patent Application No. 2010-099299), the contents of which are incorporated herein by reference.

Claims

The hydrogen atom of the hydroxyl group contained in cellulose
Having at least one group substituted in A) below and at least one group substituted in B) below,
The total molar substitution degree of the —C n H 2n —O— group contained in the group substituted with A) is 0.5 or more and 3.0 or less,
A cellulose derivative having a number average molecular weight of 150,000 or more.
A) A group containing a structure represented by the following general formula (1) B) Acyl group: —CO—R B (R B represents a hydrocarbon group having 1 to 3 carbon atoms.)

(In the general formula (1), n represents 2 or 3, and R A represents a hydrocarbon group having 1 to 3 carbon atoms.)
The cellulose derivative according to claim 1, wherein R A and R B are each independently a methyl group or an ethyl group.
The cellulose derivative according to claim 1, wherein R A and R B are methyl groups.
The total molar substitution degree of the —C n H 2n —O— group contained in the group containing the structure represented by the general formula (1) is 0.5 or more and 2.5 or less. 2. The cellulose derivative according to item 1.
The cellulose according to claim 4, wherein the total molar substitution degree of the -C n H 2n -O- group contained in the group containing the structure represented by the general formula (1) is 1.0 or more and 2.0 or less. Derivative.
The cellulose derivative according to any one of claims 1 to 5, wherein the number average molecular weight is 200,000 or more and 500,000 or less.
The cellulose derivative according to any one of claims 1 to 6, wherein the cellulose derivative is obtained by acylating hydroxyethyl cellulose, hydroxypropyl cellulose, or hydroxyethyl hydroxypropyl cellulose.
The cellulose derivative according to any one of claims 1 to 7, wherein the cellulose derivative substantially does not contain an alkoxy group.
The cellulose derivative according to any one of claims 1 to 8, wherein the cellulose derivative is non-liquid crystalline.
A resin composition containing the cellulose derivative according to any one of claims 1 to 9.
A molding material containing the cellulose derivative according to any one of claims 1 to 9, or the resin composition according to claim 10.
A molded body obtained by molding the cellulose derivative according to any one of claims 1 to 9, the resin composition according to claim 10, or the molding material according to claim 11.
Production of a molded body comprising a step of heating and molding the cellulose derivative according to any one of claims 1 to 9, the resin composition according to claim 10, or the molding material according to claim 11. Method.
A housing for electrical and electronic equipment comprising the molded body according to claim 12.