KR102405528B1 - Acrylic fiber treatment agent and its use - Google Patents

Abstract

When the acrylic fiber for carbon fiber manufacture manufactured by giving a treating agent is stored for a long period of time, the treating agent for acrylic fibers capable of suppressing deterioration of the acrylic fiber for carbon fiber manufacture, the acrylic fiber for carbon fiber manufacture using the treating agent, and carbon fibers using the treating agent It provides a manufacturing method of The acrylic fiber treatment agent of this invention contains an amino-modified silicone (A), a Bronsted-acid compound (B), and an acetylenic surfactant (C). The acrylic fiber for carbon fiber manufacture of this invention is made by making the acrylic fiber processing agent of this invention adhere to the raw material acrylic fiber of the acrylic fiber for carbon fiber manufacture.

Description

Acrylic fiber treatment agent and its use

The present invention relates to an acrylic fiber treatment agent and its use. In more detail, the processing agent used when manufacturing the acrylic fiber, the acrylic fiber for carbon fiber production using the processing agent (hereinafter also referred to as a precursor), and a method for producing carbon fibers using the processing agent will be.

Carbon fiber is widely used as a reinforcing fiber for a composite material with a plastic such as a matrix resin by utilizing its excellent mechanical properties, for aerospace applications, sports applications, general industrial applications, and the like.

As a method of manufacturing carbon fiber, the acrylic fiber for carbon fiber manufacture (it is also called a precursor) is manufactured first (the manufacturing process of this precursor is also called a spinning process). This precursor is converted into flame-resistant fibers in an oxidizing atmosphere at 200 to 300 ° C. (This step is also referred to as a carbonization treatment step hereinafter) is a common method (hereinafter, the flame resistance treatment step and the carbonization treatment step are collectively referred to as a calcination step). In the production of this precursor, a stretching step of stretching at a high magnification compared to ordinary acrylic fibers is performed. In that case, since it is easy to generate|occur|produce the aggregation of fibers, and high magnification|stretching is not performed uniformly, it becomes a non-uniform|heterogenous precursor. Carbon fibers obtained by firing such a precursor have a problem that sufficient strength cannot be obtained. In addition, when the precursor is fired, there is a problem in that the short fibers are fused to each other and the quality and quality of the obtained carbon fibers are reduced.

As a treatment agent given to a precursor to prevent agglomeration of precursors and fusion of carbon fibers, a silicone-based treatment agent having low fiber-fiber friction when wet and under high-temperature environments and excellent releasability, especially by heat A number of techniques have been proposed in which a precursor is provided with an amino-modified silicone-based treatment agent capable of further improving heat resistance by crosslinking reaction (see Patent Documents 1 and 2).

When the precursor manufactured by providing such a treatment agent was stored for a long period of time, there was a problem of causing deterioration of the precursor with time. For this reason, when carbon fiber was manufactured by baking the precursor stored for a long period of time, there existed a problem, such as fluffing in a baking process, and carbon fiber intensity|strength falling after baking.

Patent Document 1: Japanese Patent Application Laid-Open No. 2001-172879 Patent Document 2: Japanese Patent Application Laid-Open No. 2002-129481

In view of such a prior art background, an object of the present invention is an acrylic fiber treatment agent capable of suppressing deterioration of the acrylic fiber for carbon fiber production when the acrylic fiber for carbon fiber production manufactured by applying a treatment agent is stored for a long period of time, the treatment agent It is providing the manufacturing method of the carbon fiber using the used acrylic fiber for carbon fiber manufacture, and the said processing agent.

As a result of the present inventors earnestly examining in order to solve the said problem, deterioration at the time of long-term storage of the precursor manufactured by providing a processing agent originates in the amino group of the amino-modified silicone contained in a processing agent, and amino-modified It has been found that the penetration into the fibers of the emulsifier used to emulsify the silicone results. And, when the amino-modified silicone (A), the Bronsted acid compound (B), and the acetylenic surfactant (C) are used together, the precursor deteriorates due to the amino group and the precursor deteriorates due to the penetration of the emulsifier into the fiber. was found to be able to suppress, and the present invention was reached.

In other words. The acrylic fiber treatment agent of this invention contains an amino-modified silicone (A), a Bronsted-acid compound (B), and an acetylenic surfactant (C).

It is preferable that the ratio of the Bronsted acid compound (B) is 0.01-2.5 molar equivalent with respect to 1 mol of amino groups of the said amino-modified silicone (A).

It is preferable that the ratio of the acetylene-based surfactant (C) is 0.1 to 12 parts by weight based on 100 parts by weight of the amino-modified silicone (A).

The acetylene-based surfactant (C) is selected from acetylene alcohol (C1), acetylenediol (C2), a compound (C3) in which an alkylene oxide is added to acetylene alcohol (C3), and a compound (C4) in which an alkylene oxide is added to acetylene diol (C4) It is preferable that it is at least 1 type.

It is preferable that the said acetylene alcohol (C1) is a compound represented by the following general formula (1). It is preferable that the said acetylenediol (C2) is a compound represented by the following general formula (2). It is preferable that the compound (C3) which added the alkylene oxide to the said acetylene alcohol is a compound represented by the following general formula (3). The compound (C4) obtained by adding an alkylene oxide to the acetylenediol is preferably a compound represented by the following general formula (4).

[Formula 1]

(In Formula (1), R ¹ and R ² are each independently and an alkyl group having 1 to 8 carbon atoms.)

[Formula 2]

(In formula (2), R ³ , R ⁴ , R ⁵ and R ⁶ are each independently an alkyl group having 1 to 8 carbon atoms.)

[Formula 3]

(In formula (3), R ¹ and R ² are each independently an alkyl group having 1 to 8 carbon atoms. R ⁷ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. AO is an oxyalkylene group having 2 to 4 carbon atoms. Indicate, n is a number from 1 to 50.)

[Formula 4]

(In formula (4), R ³ , R ⁴ , R ⁵ and R ⁶ are each independently an alkyl group having 1 to 8 carbon atoms. R ⁷ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. A plurality of R ⁷ in ) may be the same or different. AO represents an oxyalkylene group having 2 to 4 carbon atoms. m and n are each independently and are a number from 1 to 50.)

It is preferable that the weight ratio of the said amino-modified silicone (A) to the non-volatile matter of a processing agent is 40 to 95 weight%.

It is preferable that the processing agent for acrylic fibers of this invention contains polyoxyalkylene alkyl ether (D) further.

It is preferable that the said polyoxyalkylene alkyl ether (D) contains the compound represented by following General formula (5).

[Formula 5]

(In the general formula (5), R ⁸ represents an alkyl group having 6 to 22 carbon atoms. AO represents an oxyalkylene group having 2 to 4 carbon atoms. Each j is independent and is a number from 1 to 50.)

With respect to 100 parts by weight of the amino-modified silicone (A), the ratio of the total of the acetylene-based surfactant (C) and the polyoxyalkylene alkyl ether (D) is preferably 5 to 50 parts by weight.

The acrylic fiber for carbon fiber manufacture of this invention is made by making the said acrylic fiber processing agent adhere to the raw material acrylic fiber of the acrylic fiber for carbon fiber manufacture.

The carbon fiber manufacturing method of the present invention includes a spinning process of spun by attaching the fiber treatment agent to the raw acrylic fiber of the acrylic fiber for carbon fiber manufacturing, and a flame-resistant treatment for converting into a flame-resistant fiber in an oxidizing atmosphere at 200 to 300° C. step, and a carbonization treatment step of carbonizing the flame-resistant fiber in an inert atmosphere at 300 to 2,000°C.

When the acrylic fiber processing agent of this invention preserves the acrylic fiber for carbon fiber manufacture manufactured by providing a processing agent for a long period of time, it can suppress deterioration of the acrylic fiber for carbon fiber manufacture. If the acrylic fiber for carbon fiber manufacture of this invention is used, even if it uses the acrylic fiber bundle stored for a long period of time, generation|occurrence|production of fluff in a baking process can be suppressed, and high strength and high quality carbon fiber can be obtained. According to the carbon fiber manufacturing method of this invention, even if it uses the acrylic fiber bundle stored for a long period of time, generation|occurrence|production of fluff in a baking process can be suppressed, and high strength and high quality carbon fiber can be obtained.

(Amino-modified silicone (A))

The processing agent of this invention contains amino-modified silicone (A) essentially. The amino group (including an organic group having an amino group), which is a modified group of the amino-modified silicone, may be bonded to the side chain of the silicone as the main chain, may be bonded to the terminal, or may be bonded to both, but the flame resistance From the viewpoint of fiber protection in the treatment step, it is more preferable that the side chain is bonded (having an amino group in the side chain). In addition, the amino group may be any of monoamine type, diamine type, and polyamine type, and both may coexist in one molecule. A monoamine type or a diamine type is preferable from a viewpoint of protecting a fiber by making it into a film. An amino-modified silicone (A) may be used individually by 1 type, and may be used in combination of 2 or more type.

The kinematic viscosity at 25°C of the amino-modified silicone (A) is preferably 50 to 30,000 mm ² /s from the viewpoint of exhibiting the effect of the present application. When kinematic viscosity is less than 50 mm< ² >/s, a processing agent scatters easily, and when water-system emulsification is carried out, the solution stability of an emulsion deteriorates, and it may become impossible to provide a processing agent uniformly to a fiber. As a result, there are cases where the fusion of fibers cannot be prevented. When the kinematic viscosity exceeds 30,000 mm ² /s, gum up due to adhesiveness may become a problem. The upper limit of the kinematic viscosity is preferably in the order of 25,000mm ² /s, 20,000mm ² /s, 10,000mm ² /s, 5,000mm ² /s, 4,000mm ² /s, 3,000mm ² /s, 2,500mm ² /s do.

The amino equivalent of the amino-modified silicone (A) is preferably 300 to 10,000 g/mol, more preferably 500 to 10,000 g/mol, and 1,000 to 9,000 g/mol from the viewpoint of preventing agglomeration or fusion between fibers. This is more preferable. When the amino equivalent is less than 300 g/mol, the treatment agent may not be uniformly applied to the inside of the fiber bundle because the treatment agent is thermally crosslinked at the initial stage of the flame-resistant treatment step. Moreover, when the said amino equivalent is 10,000 g/mol or more, since thermal crosslinking of a processing agent does not occur in the late stage of a flame-resistant treatment process, fiber protection may not be performed. Here, the amino equivalent means the mass of the siloxane skeleton per amino group or ammonium group. The g/mol of the indicated unit is a value converted per 1 mol of an amino group or an ammonium group. Therefore, it is shown that the ratio of an amino group or an ammonium group in a molecule|numerator is so high that the value of an amino equivalent is small.

The amino-modified silicone (A) may use together a plurality of amino-modified silicones having different amino equivalents and kinematic viscosities (25°C). When two or more amino-modified silicones are used, the amino equivalent means the amino equivalent of the entire amino-modified silicone (mixture), and the kinematic viscosity at 25° C. means the kinematic viscosity of the entire amino-modified silicone (mixture).

As said amino-modified silicone, the compound represented by following General formula (6) is mentioned, for example.

[Formula 6]

(In formula (6), R ⁹ represents an alkyl group or aryl group having 1 to 20 carbon atoms. R ¹⁰ is a group represented by the following formula (7). R ¹¹ is R ⁹ , R ¹⁰ or -OR ¹⁷ (R ¹⁷ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.) p is 10≤p≤10,000, q is 0.1≤q≤1,000.)

In formula (6), R< ⁹ > represents a C1-C20 alkyl group or an aryl group. R ⁹ is preferably an alkyl group or aryl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, and still more preferably a methyl group. In addition, some R< ⁹ > in Formula (6) may be the same or different. R ¹⁰ is a group represented by the following general formula (7). R11 is a group represented by R ⁹ , R ¹⁰ or -OR ¹⁷ , preferably R ⁹ . In addition, a plurality of R ¹¹ in Formula (6) may be the same or different.

R ¹⁷ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and more preferably a hydrogen atom or a methyl group. p is a number of 10 to 10,000, preferably 50 to 5,000, and more preferably 100 to 2,000. q is a number of 0.1-1,000, Preferably it is 0.5-500, More preferably, it is 1-100.

[Formula 7]

In formula (7), R ¹² and R ¹⁴ are each independently and are an alkylene group having 1 to 6 carbon atoms, preferably an alkylene group having 1 to 3 carbon atoms. R ¹³ , R ¹⁵ and R ¹⁶ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group, preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and more preferably a hydrogen atom. r is a number of 0-6, Preferably it is 0-3, More preferably, it is 0-1.

(Bronsted acid compound (B))

The fiber treatment agent of this invention contains the Bronsted acid compound (B) essentially. When the Bronsted acid (B) is not used, even when an acetylene-based surfactant (C), which is an essential component, is used, crosslinking with time due to the amino group of the amino-modified silicone cannot be suppressed. The Bronsted acid compound (B) refers to a proton donor, and examples thereof include a carboxylic acid compound, an inorganic acid, a sulfonic acid compound, and a phosphonic acid compound. A Bronsted-acid compound (B) may be used individually by 1 type, and may be used in combination of 2 or more type.

The carboxylic acid compound refers to a compound containing a carboxyl group in its molecular structure. Although there is no limitation in particular as a carboxylic acid compound, An aliphatic monocarboxylic acid, an aliphatic polycarboxylic acid, an aromatic carboxylic acid, an aromatic polycarboxylic acid, an amino acid, etc. are mentioned.

Examples of the aliphatic monocarboxylic acid include acetic acid, lactic acid, butanoic acid, crotonic acid, valeric acid, caproic acid, enantic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, myristic acid, pentanic acid Decanoic acid, palmitic acid, palmitoleic acid, isocetyl acid, margaric acid, stearic acid, isostearic acid, oleic acid, elaidic acid, vaccenic acid, linoleic acid, linolenic acid, arachidic acid, isoeicosaic acid, gadoleic acid, eico Senic acid, docoxic acid, isodocosan acid, erucic acid, tetracosan acid, isotetracoic acid, nervonic acid, serotinic acid, montanic acid, melicic acid, polyoxyalkylene monocarboxylic acid, polyoxyalkylene alkyl ether monocarboxylic acid and the like.

As aliphatic polycarboxylic acids, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetra Decanedioic acid, pentadecanedioic acid, polyoxyalkylenedicarboxylic acid, polyoxyalkylenealkyletherdicarboxylic acid, and derivatives thereof are mentioned.

As aromatic monocarboxylic acid, benzoic acid, cinnamic acid, naphthoic acid, toluic acid, and these derivatives are mentioned.

Examples of the aromatic polycarboxylic acid include phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid and pyromellitic acid, and derivatives thereof.

Amino acids are compounds having both an amino group and a carboxyl group in their molecular structure, and alanine, valine, leucine, isoleucine, phenylalanine, tryptophan, methionine, proline, glycine, tyrosine, serine, threonine, cysteine, asparagine, glutamine, lysine, arginine , histidine, aspartic acid, glutamic acid, and the like.

An inorganic acid refers to an acid containing non-metal atoms as a component. Sulfuric acid, nitric acid, phosphoric acid, hydrochloric acid etc. are mentioned as an inorganic acid.

Examples of the sulfonic acid compound include alkylbenzenesulfonic acid, polyoxyalkylenealkylethersulfonic acid, higher fatty acid amidesulfonic acid, alkylsulfuric acid monoester, and polyoxyalkylenesulfonic acid monoester.

Examples of the phosphonic acid compound include alkylphosphonic acid, aromatic phosphonic acid, polyoxyalkylenealkyletherphosphonic acid, and alkylphosphonic acid alkylphosphonic acid monoester.

The pKa of the Brønsted compound (B) is preferably 0 to 7, more preferably 1 to 6.5, from the viewpoint of corrosion and safety of equipment, and from the viewpoint of suppression of crosslinking over time due to the amino group of the amino-modified silicone. , 2 to 6 are more preferable.

(Acetylene-based surfactant (C))

The acrylic fiber treatment agent of this invention contains an acetylenic surfactant (C) essentially. With respect to the amino-modified silicone, by using the Bronsted acid compound (B) and the acetylene-based surfactant (C) together, it is possible to suppress crosslinking over time due to the amino group of the amino-modified silicone and to emulsify the amino-modified silicone in water. It is estimated that it can suppress that the emulsifier at a time permeates inside a fiber structure, and, as a result, can suppress deterioration of the precursor fiber when a precursor fiber is stored for a long period of time. When an acetylene-based surfactant (C) is not used and other surfactants are used, even when a Bronsted acid compound (B) is used, the penetration of the emulsifier into the fiber structure cannot be suppressed, and as a result, precursor fibers When carbon fiber is manufactured using the precursor fiber at the time of long-term storage, it is estimated that the intensity|strength will fall. In addition, an acetylenic surfactant refers to the compound which has hydrophilic groups, such as an acetylene group and a hydroxyl group, in a molecular structure. An acetylenic surfactant (C) may be used individually by 1 type, and may be used in combination of 2 or more type.

The acetylene surfactant (C) is selected from acetylene alcohol (C1), acetylenediol (C2), a compound (C3) obtained by adding an alkylene oxide to acetylene alcohol, and a compound (C4) obtained by adding an alkylene oxide to acetylene diol It is preferable that it is at least 1 type. Among these, a compound (C3) obtained by adding an alkylene oxide to acetylene alcohol and a compound (C4) obtained by adding an alkylene oxide to acetylene diol are preferred, and a compound (C4) obtained by adding an alkylene oxide to acetylene diol is more preferred. .

Acetylene alcohol (C1) is a compound having an acetylene group and one hydroxyl group in its molecular structure.

It is preferable that acetylene alcohol (C1) is a compound represented by the said General formula (1).

Acetylenediol (C2) is a compound having an acetylene group and two hydroxyl groups in its molecular structure.

It is preferable that acetylenediol (C2) is a compound represented by the said General formula (2).

The compound (C3) obtained by adding an alkylene oxide to acetylene alcohol is a compound obtained by adding an alkylene oxide to the hydroxyl group of acetylene alcohol.

It is preferable that the compound (C3) which added alkylene oxide to acetylene alcohol is a compound represented by the said General formula (3).

The compound (C4) obtained by adding an alkylene oxide to acetylenediol is a compound obtained by adding an alkylene oxide to at least one of the hydroxyl groups of acetylenediol.

It is preferable that the compound (C4) which added alkylene oxide to acetylenediol is a compound represented by the said General formula (4).

In Formulas (1) and (3), R ¹ and R ² are each independently an alkyl group having 1 to 8 carbon atoms. The said alkyl group may be linear and may have a branched structure. Carbon number of the said alkyl group becomes like this. Preferably it is 1-7, More preferably, it is 1-6, More preferably, it is 1-5.

In formulas (2) and (4), R ³ , R ⁴ , R ⁵ and R ⁶ are each independently an alkyl group having 1 to 8 carbon atoms. The said alkyl group may be linear and may have a branched structure. Carbon number of the said alkyl group becomes like this. Preferably it is 1-7, More preferably, it is 1-6, More preferably, it is 1-5.

In formulas (3) and (4), R ⁷ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Carbon number of the said alkyl group becomes like this. Preferably it is 1-4, More preferably, it is 1-3, More preferably, it is 1-2.

In formulas (3) and (4), AO represents an oxyalkylene group having 2 to 4 carbon atoms. That is, an oxyethylene group, an oxypropylene group, or an oxybutylene group is shown. As an oxyalkylene group, an oxyethylene group and an oxypropylene group are preferable, and an oxyethylene group is more preferable. The number of AO constituting (AO) _n or (AO) _m may be one, or two or more types may be sufficient as them. In the case of two or more types, any of a block adduct, an alternating adduct, and a random adduct may be sufficient.

In formula (3), n is a number from 1 to 50. 1-45 are preferable, as for n, 1-40 are more preferable, and 1-35 are still more preferable.

In formula (4), m and n are each independent and are a number from 1 to 50. m and n are each independent, 1-45 are preferable, 1-40 are more preferable, and 1-35 are still more preferable.

From an emulsifiable viewpoint, 4-25 are preferable, 5-20 are more preferable, and, as for HLB of an acetylenic surfactant (C), 6-18 are still more preferable. HLB in the present invention can be experimentally obtained by the Atlas method proposed by Griffin et al.

The acetylenic surfactant (C) is a known compound and can be easily produced by a known method. For example, such a compound can be obtained by a method called Leppe reaction, wherein a ketone or an aldehyde is reacted with acetylene in the presence of a catalyst such as an alkali or a metal compound under pressure.

In addition, the compound (C3) or compound (C4) is acetylene alcohol (C1) or acetylene diol (C2) with alkylene oxide (for example, ethylene oxide and/or propylene oxide), respectively. A catalyst such as an alkali or a metal compound It can be obtained by addition polymerization in the presence of.

[Acrylic Fiber Treatment Agent]

The processing agent for acrylic fibers of this invention contains the said amino-modified silicone (A), a Bronsted-acid compound (B), and an acetylenic surfactant (C).

The weight ratio of the amino-modified silicone (A) to the nonvolatile matter of the treating agent is preferably 40 to 95% by weight, more preferably 45 to 94% by weight, still more preferably 50 to 92% by weight, particularly preferably 55-90% by weight. When the said weight ratio is less than 40 weight%, the heat resistance of a processing agent in a flame-resistant treatment process may be insufficient. On the other hand, when the said weight ratio is more than 95 weight%, when a processing agent is emulsified in aqueous system, a stable aqueous emulsion may not be obtained.

The weight ratio of the acetylenic surfactant (C) to the nonvolatile matter of the treating agent is preferably 0.1 to 20% by weight, more preferably 0.2 to 15% by weight, still more preferably 0.3 to 13% by weight, particularly preferably is 0.5 to 10% by weight. When the above weight ratio is less than 0.1% by weight, the penetration of the emulsifier into the fiber structure cannot be suppressed in some cases. On the other hand, when the said weight ratio is more than 20 weight%, stable operability may not be acquired.

It is preferable that the ratio of the acetylenic surfactant (C) to 100 parts by weight of the amino-modified silicone (A) is 0.1 to 12 parts by weight from the viewpoint of achieving both stable operability and storage stability of the precursor. The proportion is preferably 0.2 to 11 parts by weight, more preferably 0.2 to 10 parts by weight, and still more preferably 0.5 to 8 parts by weight. When the ratio is less than 0.1 parts by weight, there may be cases in which the penetration of the emulsifier into the fiber structure cannot be suppressed. On the other hand, when the ratio is more than 12 parts by weight, stable operability may not be obtained.

The proportion of the Bronsted acid compound (B) is preferably 0.01 to 2.5 molar equivalents with respect to 1 mol of the amino group of the amino-modified silicone (A) from the viewpoint of suppressing the crosslinking caused by the amino group of the amino-modified silicone over time. do. The said ratio becomes like this. Preferably it is 0.05-2.25 molar equivalent, More preferably, it is 0.1-2.0 molar equivalent, More preferably, it is 0.12-1.5 molar equivalent. When the said ratio is less than 0.01 equivalent, suppression of the crosslinking|crosslinking resulting from the amino group of an amino-modified silicone may not be performed in some cases. On the other hand, when the ratio exceeds 2.5 equivalents, gum up is promoted in the process, and stable operability may not be obtained.

(polyoxyalkylene alkyl ether (D))

It is preferable that the processing agent of this invention contains polyoxyalkylene alkyl ether (D) from a viewpoint which can improve emulsification property. In addition, polyoxyalkylene alkyl ether is a compound having a structure in which an alkylene oxide is added to a saturated aliphatic alcohol, in the general formula (5), R ⁸ is an alkyl group, AO is an oxyalkylene group having 2 to 4 carbon atoms, j denotes a number greater than or equal to 1. Polyoxyalkylene alkyl ether (D) may be used individually by 1 type, and may be used in combination of 2 or more type.

As polyoxyalkylene alkyl ether, For example, polyoxyethylene hexyl ether, polyoxyethylene heptyl ether, polyoxyethylene octyl ether, polyoxyethylene decyl ether, polyoxyethylene lauryl ether, polyoxyethylene tridecyl ether, polyoxyalkylene linear alkyl ethers such as polyoxyethylene tetradecyl ether and polyoxyethylene cetyl ether; polyoxyalkylene branched primary alkyl ethers such as polyoxyethylene 2-ethylhexyl ether, polyoxyethylene isocetyl ether, and polyoxyethylene isostearyl ether; Polyoxyethylene 1-hexylhexyl ether, polyoxyethylene 1-octylhexyl ether, polyoxyethylene 1-hexyl octyl ether, polyoxyethylene 1-pentylheptyl ether, polyoxyethylene 1-heptylpentyl ether, polyoxyethylene 1 - Polyoxyalkylene branched secondary alkyl ethers, such as hexylheptyl ether, polyoxyethylene 1-heptylhexyl ether, polyoxyethylene 1-pentyl capthyl ether, and polyoxyethylene 1-capthyl pentyl ether, etc. are mentioned. .

It is preferable that polyoxyalkylene alkyl ether (D) contains the compound represented by the said General formula (5) essentially from a viewpoint of exhibiting the effect of this application. In the general formula (5), R ⁸ is an alkyl group having 6 to 22 carbon atoms. When R ⁸ is a hydrocarbon group other than an alkyl group and the carbon number of R ⁸ is more than 22, the polyoxyalkylene alkyl ether is tarred in the flame-resistant treatment process, so that the disadvantage when the precursor is converted into a flame-resistant structure is This may cause a decrease in the strength of the carbon fiber. On the other hand, when carbon number of R< ⁸ > is less than 6, the solution stability of the emulsion at the time of aqueous emulsification of a processing agent may deteriorate. 8-20 are preferable, as for carbon number of R< ⁸ >, 10-18 are more preferable, and 10-16 are still more preferable. Distribution may exist in carbon number of R< ⁸ >, and R< ⁸ > may be linear or may have a branch.

A represents a C2-C4 alkylene group, and AO represents an oxyalkylene group. That is, an oxyethylene group, an oxypropylene group, or an oxybutylene group is shown. As an oxyalkylene group, an oxyethylene group and an oxypropylene group are preferable, and an oxyethylene group is more preferable. j which is the repeating number of an oxyalkylene group is the number of 1-50, 2-40 are preferable and 3-30 are more preferable. When n is more than 30, when used in combination with the amino-modified silicone, fusion may occur because the treatment agent cannot be uniformly applied to the inside of the fiber bundle in the flame-resistant treatment step. One type may be sufficient as AO which comprises polyoxyalkylene group (AO) _j , and 2 or more types may be sufficient as it. In the case of two or more types, any of a block adduct, an alternating adduct, and a random adduct may be sufficient. j in AO is the added mole number of an oxyalkylene group.

When a processing agent contains polyoxyalkylene alkyl ether (D), it is preferable that the weight ratio of the polyoxyalkylene alkyl ether (D) to a non-volatile matter of a processing agent is 2 to 25 weight%, and 5 to 20 weight % is more preferable, and 10 to 20 weight% is still more preferable. When the said weight ratio is less than 2 weight% and aqueous emulsification of a processing agent, a stable aqueous emulsion may not be obtained. On the other hand, when the said weight ratio is more than 25 weight%, the heat resistance of a processing agent in a flame-resistant treatment process may run short.

From the viewpoint of improving the long-term storage stability of the precursor, the ratio of the total of the acetylene-based surfactant (C) and the polyoxyalkylene alkyl ether (D) to 100 parts by weight of the amino-modified silicone (A) is 5 to 50 parts by weight it is preferable When the said ratio is less than 5 weight part, emulsion stability may deteriorate. On the other hand, when the said weight part exceeds 50 weight part, stable operability may not be acquired.

(Other surfactants)

The acrylic fiber processing agent of this invention may contain surfactant other than the said acetylene type surfactant (C) and polyoxyalkylene alkyl ether (D) in the range which does not impair the effect of this invention. Surfactants are used as emulsifiers, antistatic agents, and the like. There is no limitation in particular as surfactant, Nonionic surfactant other than the said acetylene surfactant (C) and polyoxyalkylene alkyl ether (D), anionic surfactant, cationic surfactant, and amphoteric surfactant A well-known one can be appropriately selected and used. The number of surfactant may be one, and may use 2 or more types together.

As nonionic surfactants other than the said acetylene surfactant (C) and polyoxyalkylene alkyl ether (D), For example, Polyoxyalkylene alkenyl ether, such as polyoxyethylene oleyl ether; polyoxyalkylene alkylphenyl ethers such as polyoxyethylene octylphenyl ether, polyoxyethylene nonylphenyl ether, and polyoxyethylene dodecylphenyl ether; Polyoxyethylene tristyryl phenyl ether, polyoxyethylene distyryl phenyl ether, polyoxyethylene styryl phenyl ether, polyoxyethylene tribenzyl phenyl ether, polyoxyethylene dibenzyl phenyl ether, polyoxyethylene benzyl phenyl ether, etc. oxyalkylenealkylarylphenylether; Polyoxyethylene monolaurate, polyoxyethylene monooleate, polyoxyethylene monostearate, polyoxyethylene monomyristylate, polyoxyethylene dilaurate, polyoxyethylene diolate, polyoxyethylene dimyristylate, polyoxyalkylene fatty acid esters such as polyoxyethylene distearate; sorbitan esters such as sorbitan monopalmitate and sorbitan monooleate; polyoxyalkylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monostearate and polyoxyethylene sorbitan monooleate; glycerin fatty acid esters such as glycerin monostearate, glycerin monolaurate, and glycerin monopalmitate; polyoxyalkylenesorbitol fatty acid esters; sucrose fatty acid esters; polyoxyalkylene castor oil ethers such as polyoxyethylene castor oil ether; polyoxyalkylene hydrogenated castor oil ethers such as polyoxyethylene hydrogenated castor oil ether; oxyethylene-oxypropylene block or random copolymers; terminal sucrose ethers of oxyethylene-oxypropylene block or random copolymers; and the like. 2,000 or less are preferable, as for the weight average molecular weight of a nonionic surfactant, 200-1,800 are more preferable, 300-1,500 are more preferable, 500-1,000 are still more preferable.

Examples of the anionic surfactant include fatty acid salts such as sodium oleate, potassium palmitate, and triethanolamine oleate; hydroxyl group-containing carboxylates such as potassium hydroxyacetate and potassium lactate; polyoxyalkylene alkyl ether acetates such as sodium polyoxyethylene tridecyl ether acetate; salts of carboxyl group polysubstituted aromatic compounds such as potassium trimellitate and potassium pyromellitate; alkylbenzene sulfonates such as sodium dodecylbenzene sulfonate; polyoxyalkylene alkyl ether sulfonates, such as polyoxyethylene 2-ethylhexyl ether sulfonic acid potassium salt; higher fatty acid amide sulfonates, such as sodium stearoylmethyl taurine, sodium lauroyl methyl taurine, sodium myristyl methyl taurine, and sodium palmitoyl methyl taurine; N-acyl sarcosinates, such as sodium lauroyl sarcosate; Alkyl phosphonate salts, such as an octyl phosphonate potassium salt; Aromatic phosphonate salts, such as phenyl phosphonate potassium salt; Alkyl phosphonic acid alkyl phosphate ester salts, such as 2-ethylhexyl phosphonate mono2-ethylhexyl ester potassium salt; nitrogen-containing alkylphosphonic acid salts such as aminoethylphosphonic acid diethanolamine salt; Alkyl sulfate ester salts, such as 2-ethylhexyl sulfate sodium salt; polyoxyalkylene sulfate ester salts such as polyoxyethylene 2-ethylhexyl ether sulfate sodium salt; Long-chain N such as sodium di-2-ethylhexyl sulfosuccinate and sodium dioctyl sulfosuccinate, monosodium N-lauroyl glutamate, and disodium N-stearoyl-L-glutamate -Acyl glutamate, etc. are mentioned.

As cationic surfactant, for example, lauryl trimethyl ammonium chloride, myristyl trimethyl ammonium chloride, palmityl trimethyl ammonium chloride, stearyl trimethyl ammonium chloride, oleyl trimethyl ammonium chloride, cetyl trimethyl ammonium chloride, behenyl trimethyl ammonium chloride , palm oil alkyltrimethylammonium chloride, tallow alkyltrimethylammonium chloride, stearyltrimethylammonium bromide, palm oil alkyltrimethylammonium bromide, cetyltrimethylammonium methosulfate, oleyldimethylethylammoniumethsulfate, dioctyldimethylammonium alkyl quaternary ammonium salts such as chloride, dilauryl dimethyl ammonium chloride, distearyl dimethyl ammonium chloride and octadecyl diethyl methyl ammonium sulfate; (polyoxyethylene) laurylamino ether lactate, stearylamino ether lactate, di(polyoxyethylene)laurylmethylaminoetherdimethyl phosphate, di(polyoxyethylene)laurylethylammonium ethsulfate, di(polyoxyethylene) (polyoxyalkylene)alkylaminoether salts such as ethylene) hydrogenated tallow alkylethylamine ethsulfate, di(polyoxyethylene)laurylmethylammonium dimethyl phosphate, and di(polyoxyethylene)stearylamine lactate; N-(2-hydroxyethyl)-N,N-dimethyl-N-stearoylamidepropylammonium nitrite, lanolin fatty acid amidepropylethyldimethylammonium ethsulfate, lauroylamideethylmethyldiethylammonium methosulfate, etc. acylamidealkyl quaternary ammonium salts; alkylethenoxy quaternary ammonium salts such as dipalmitylpolyethenoxyethylammonium chloride and distearylpolyethenoxymethylammonium chloride; alkyl isoquinolinium salts such as lauryl isoquinolinium chloride; benzarconium salts such as lauryl dimethyl benzyl ammonium chloride and stearyl dimethyl benzyl ammonium chloride; benzethnium salts such as benzyldimethyl {2-[2-(p-1,1,3,3-tetramethylbutylphenoxy)ethoxy]ethyl}ammonium chloride; pyridinium salts such as cetylpyridinium chloride; imidazolinium salts such as oleylhydroxyethylimidazoliniumethosulfate and laurylhydroxyethylimidazoliniumethosulfate; acyl basic amino acid alkyl ester salts such as N-cocoylarginine ethyl ester pyrrolidone carboxylate and N-lauroyl lysine ethyl ethyl ester chloride; primary amine salts such as laurylamine chloride, stearylamine bromide, hydrogenated tallow alkylamine chloride, and rosinamine acetate; secondary amine salts such as cetylmethylamine sulfate, laurylmethylamine chloride, dilaurylamine acetate, stearylethylamine bromide, laurylpropylamine acetate, dioctylamine chloride, and octadecylethylamine hydroxide; Dilaurylmethylamine sulfate, lauryldiethylamine chloride, laurylethylmethylaminebromide, diethanolstearylamideethylaminetrihydroxyethylphosphate salt, stearylamideethylethanolamine urea polycondensate acetate salt tertiary amine salts such as; fatty acid amide guanidinium salts; Alkyl trialkylene glycol ammonium salts, such as lauryl triethylene glycol ammonium hydroxide, etc. are mentioned.

As the amphoteric surfactant, for example, 2-undecyl-N,N-(hydroxyethylcarboxymethyl)-2-imidazoline sodium, 2-cocoyl-2-imidazolinium hydroxide-1-carboxy imidazoline-based amphoteric surfactants such as ethyloxy disodium salt; betaine-based amphoteric surfactants such as 2-heptadecyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, lauryldimethylaminoacetic acid betaine, alkyl betaine, amide betaine and sulfobetaine; Amino acid type amphoteric surfactants, such as N-lauryl glycine, N-lauryl beta-alanine, and N-stearyl beta-alanine, etc. are mentioned.

(Other ingredients)

The acrylic fiber processing agent of this invention may contain other components other than an above-described component in the range which does not impair the effect of this invention. As another component, Antioxidants, such as acidic phosphoric acid ester, a phenol type, an amine type, a sulfur type, phosphorus type, a quinone type; antistatic agents such as sulfate ester salts of higher alcohols and higher alcohol ethers, sulfonic acid salts, phosphate ester salts of higher alcohols and higher alcohol ethers, quaternary ammonium salt-type cationic surfactants, and amine salt-type cationic surfactants; leveling agents such as alkyl esters of higher alcohols, higher alcohol ethers, and wax types; antibacterial agents; antiseptic; rustproof agents; and moisture absorbents.

Moreover, the processing agent of this invention may also contain modified silicones other than said amino-modified silicone in the range which does not impair the effect of this invention. Examples of the modified silicone include aminopolyether-modified silicone, amide-modified silicone, amide polyether-modified silicone, epoxy-modified silicone, polyether-modified silicone, epoxy polyether-modified silicone (see, for example, Japanese Patent No. 4616934), and Carr A vinol-modified silicone, an alkyl-modified silicone, a phenol-modified silicone, a methacrylate-modified silicone, an alkoxy-modified silicone, a fluorine-modified silicone, etc. are mentioned, One type of modified silicone may be used, and a plurality of modified silicones may be used together.

In the acrylic fiber treatment agent of the present invention, amino-modified silicone (A), a Bronsted acid compound (B) and an acetylene-based surfactant (C), and optionally polyoxyalkylene alkyl ether (D) are dissolved in water, solubilized, It is preferably in an emulsified or dispersed state.

It does not specifically limit about the weight ratio of the water which occupies for the whole acrylic fiber processing agent, and the weight ratio of a nonvolatile matter. For example, what is necessary is just to consider the transport cost at the time of transporting the acrylic fiber processing agent of this invention, the handleability by emulsion viscosity, etc., and just to determine suitably. 0.1 to 99.9 weight% is preferable, as for the weight ratio of the water to the whole acrylic fiber processing agent, 10 to 99.5 weight% is more preferable, 50 to 99 weight% is especially preferable. 0.01 to 99.9 weight% is preferable, as for the weight ratio (concentration) of the nonvolatile matter to the whole acrylic fiber processing agent, 0.5 to 90 weight% is more preferable, 1 to 50 weight% is especially preferable.

The acrylic fiber processing agent of this invention can be manufactured by mixing the component demonstrated above. It does not specifically limit about the method of emulsifying and dispersing the component demonstrated above, A well-known method is employable. As such a method, for example, each component constituting the acrylic fiber treatment agent is poured into hot water under stirring to emulsify and disperse, or each component constituting the acrylic fiber treatment agent is mixed and homogenizer, homomixer , a method of gradually adding water while applying a mechanical shearing force using a ball mill or the like to perform phase inversion emulsification, and the like.

The acrylic fiber processing agent of this invention can be used suitably as a processing agent (precursor processing agent) of the acrylic fiber (precursor) for carbon fiber manufacture. You may use it as a spinning oil agent of acrylic fibers other than a precursor.

From the viewpoint of imparting good bundling properties of the fiber bundles in the precursor spinning process or the flame-resistant process, the viscosity at 25° C. of the nonvolatile matter of the acrylic fiber treatment agent of the present invention is preferably 10 to 50,000 mPa·s, and the viscosity When is less than 10 mPa·s, the bundling property of the fiber bundles in the precursor spinning process or the flame-resistant process may deteriorate. Moreover, when the said viscosity exceeds 50,000 mPa*s, even if good fiber bundle bundling property can be provided in a precursor spinning process or a flame-resistant process, the viscosity of a processing agent may become high too much and handleability of a processing agent may deteriorate. The viscosity is preferably in the order of 10 to 25,000 mPa·s, 10 to 15,000 mPa·s, 10 to 10,000 mPa·s, 10 to 5,000 mPa·s, and 50 to 1,000 mPa·s.

[Acrylic fiber for carbon fiber production, its production method and carbon fiber production method]

The acrylic fiber for carbon fiber manufacture (precursor) of this invention made the acrylic fiber processing agent mentioned above adhere to the raw material acrylic fiber of a precursor, and was spun. The manufacturing method of the precursor of this invention includes the spinning process of making the acrylic fiber processing agent mentioned above adhere to the raw material acrylic fiber of a precursor, and spinning.

The carbon fiber manufacturing method of the present invention is a spinning process in which a precursor is made by attaching the above-mentioned acrylic fiber treatment agent to the raw material acrylic fiber of the precursor, and the precursor prepared in the spinning process is flame-resistant in an oxidizing atmosphere at 200 to 300 ° C. A flame-resistant treatment step of converting the fiber to a carbonization treatment step of carbonizing the flame-resistant fiber in an inert atmosphere at 300 to 2,000°C.

According to the method for producing carbon fibers of the present invention, since the acrylic fiber treatment agent of the present invention is used, the treatment agent can be uniformly applied from the initial stage of the flame-resistant treatment step to the inside of the fiber bundle, and the treatment agent is used in the later stage of the flame-resistant treatment step. Since the fibers can be protected by forming a film, fusion between fibers and generation of fluff can be suppressed, and high-quality carbon fibers can be manufactured.

A spinning process is a process of making an acrylic fiber processing agent adhere to the raw material acrylic fiber of a precursor, and spinning a precursor, and includes an adhesion processing process and an extending process.

The adhesion treatment step is a step of attaching the acrylic fiber treatment agent after spinning the raw material acrylic fiber of the precursor. That is, an acrylic fiber treatment agent is made to adhere to the raw material acrylic fiber of a precursor in an adhesion treatment process. Moreover, although the raw material acrylic fiber of this precursor is extended immediately after spinning|fiber-formation, high-magnification drawing after an adhesion treatment process is especially called "stretching process". The stretching process may be a wet-heat stretching method using high-temperature steam or a dry-heat stretching method using a hot roller.

The precursor is composed of an acrylic fiber mainly composed of polyacrylonitrile obtained by copolymerizing at least 95 mol% or more of acrylonitrile with 5 mol% or less of a flame retardant promoting component. As a flameproofing acceleration|stimulation component, the vinyl group containing compound which has copolymerizability with respect to acrylonitrile can be used preferably. Although there is no limitation in particular about the single fiber fineness of a precursor, From the balance of performance and manufacturing cost, Preferably it is 0.1-2.0 dTex. Moreover, although there is no restriction|limiting in particular also about the number of short fibers which comprise the fiber bundle of a precursor, Considering the balance of performance and manufacturing cost, Preferably it is 1,000-96,000.

Although you may make an acrylic fiber processing agent adhere to the raw material acrylic fiber of a precursor at any stage of a spinning process, it is preferable to stick once before an extending process. If it is a step before an extending|stretching process, you may make it adhere at any step, for example immediately after spinning|spinning. In addition, you may make it adhere again at any stage after an extending process, for example, you may make it adhere again immediately after an extending process, you may make it adhere again at a winding-up step, You may make it adhere again just before a flame-resistant treatment process. Regarding the method of attachment, it may be attached using a roller or the like, or may be attached by an immersion method, a spray method, or the like.

In the adhesion treatment step, the rate of application of the acrylic fiber treatment agent is a balance between obtaining the effect of preventing agglutination or fusion between fibers and preventing deterioration of carbon fiber quality due to the tar material of the treatment agent in the carbonization treatment step. In consideration, it is preferably 0.1 to 2% by weight, more preferably 0.3 to 1.5% by weight, based on the weight of the precursor. When the provision rate of the acrylic fiber treatment agent is less than 0.1% by weight, the adhesion and fusion between the short fibers cannot be sufficiently prevented, and the strength of the carbon fibers obtained may be lowered. On the other hand, when the provision rate of the acrylic fiber treatment agent exceeds 2% by weight, the acrylic fiber treatment agent covers between the short fibers more than necessary, so that the supply of oxygen to the fibers in the flameproof treatment step is hindered, and the strength of the carbon fibers obtained is lowered. there is In addition, the provision rate of the acrylic fiber treating agent here is defined as the percentage of the weight of the non-volatile matter adhering to the acrylic fiber treating agent with respect to the precursor weight.

A flame-resistant treatment process is a process of converting the precursor to which the acrylic fiber processing agent adhered into a flame-resistant fiber in 200-300 degreeC oxidizing atmosphere. An oxidizing atmosphere should just be an air atmosphere normally. The temperature of the oxidizing atmosphere is preferably 230 to 280°C. In the flame-resistant treatment step, heat treatment is performed for 20 to 100 minutes (preferably 30 to 60 minutes) while applying a tension of a draw ratio of 0.90 to 1.10 (preferably 0.95 to 1.05) to the acrylic fiber after the adhesion treatment. In this flame-resistant treatment, a flame-resistant fiber having a flame-resistant structure is produced through molecular cyclization and oxygen addition to the ring.

The carbonization treatment step is a step in which the flame-resistant fiber is further carbonized in an inert atmosphere at 300 to 2,000°C. In the carbonization treatment step, first, in an inert atmosphere such as nitrogen or argon, a tension of 0.95 to 1.15 is applied to the flame-resistant fiber in a kiln having a temperature gradient from 300°C to 800°C. It is preferable to perform a preliminary carbonization treatment step (first carbonization treatment step) by heat-treating for several minutes. After that, in order to further advance carbonization and further promote graphitization, in an inert atmosphere such as nitrogen or argon, heat treatment is performed for a few minutes while applying a tension with a draw ratio of 0.95 to 1.05 with respect to the first carbonization treatment step to the second A carbonization treatment process is performed, and the flame-resistant fiber is carbonized. Regarding control of the heat treatment temperature in the second carbonization treatment step, it is preferable to set the maximum temperature to 1,000°C or more (preferably 1,000 to 2,000°C) while applying a temperature gradient. This maximum temperature is appropriately selected and determined according to the desired properties (tensile strength, elastic modulus, etc.) of the desired carbon fiber.

In the method for producing carbon fibers of the present invention, when a carbon fiber having a higher elastic modulus is desired, the graphitization treatment step may be performed following the carbonization treatment step. The graphitization treatment step is usually performed at a temperature of 2,000 to 3,000°C while applying tension to the fibers obtained in the carbonization treatment step in an inert atmosphere such as nitrogen or argon.

The carbon fiber thus obtained can be subjected to a surface treatment to increase the adhesive strength with the matrix resin in the case of a composite material depending on the purpose. As a surface treatment method, gaseous-phase or liquid-phase treatment can be employ|adopted, and from a viewpoint of productivity, liquid-phase treatment by electrolyte solutions, such as an acid and an alkali, is preferable. In addition, in order to improve the workability and handleability of the carbon fiber, various sizing agents excellent in compatibility with the matrix resin may be provided.

Example

Hereinafter, although an Example demonstrates this invention concretely, it is not limited to the Example described here. In addition, the percentage (%) and part (part) shown in a following example show "weight%" and "part by weight" unless specifically limited. Measurement of each characteristic value is performed based on the method shown below.

<Provide rate of treatment agent>

After alkali-melting the precursor after processing agent provision with potassium hydroxide/sodium butyrate, it melt|dissolved in water and adjusted to pH 1 with hydrochloric acid. Sodium sulfite and ammonium molybdate were added to this to develop color, the colorimetric determination (wavelength of 815 mmicro) of silica molybdenum blue was performed, and silicon content was calculated|required. The provision rate (weight%) of the acrylic fiber processing agent was computed using the silicon content calculated|required here and the value of the silicon content in the processing agent calculated|required by the same method previously.

<Fusion prevention property>

Twenty locations were randomly selected from carbon fibers, short fibers having a length of 10 mm were cut out therefrom, the fusion state was observed, and the evaluation criteria were determined below.

◎: No fusion

○: Almost no fusion

△: less fusion

×: a lot of fusion

<Strand hardness of precursor>

The hardness of the precursor strand (length: about 50 cm) was measured with a touch tester (HANDLE-O-METERHOM-2 Daiei Chemicals Industries, Ltd., slit width 5 mm). And the measurement was performed 10 times, and it was judged that the precursor strand was softer, so that the average value was small. In the evaluation, precursors immediately after production (within 7 days after production) and precursors stored at room temperature for 12 months after production (indicated as after storage in the table) were used.

<Abrasion resistance>

The precursor strand (12K) was rubbed 1,000 times with a tension of 50 g with three mirror chrome-plated stainless steel needles arranged in a zigzag with a TM friction bonding force tester TM-200 (manufactured by Daiei Chemical Seiki Co., Ltd.) (reciprocating). Movement speed 300 times/min) and the fluff generation state of the precursor strands were visually determined based on the following criteria. In the evaluation, a precursor immediately after production (within 7 days after production) and a precursor stored at room temperature for 12 months after production were used.

◎: No fluffing was seen at all, the same as before abrasion.

○: A few fluffs are seen, but abrasion resistance is good

△: There is a lot of fluff and abrasion resistance is slightly deteriorated

x: There are many fluffs, and remarkable short fiber breakage is seen. Poor abrasion resistance

<Carbon fiber strength>

It measured according to the epoxy resin-impregnated strand method prescribed|regulated to JIS-R-7601, and the average value of 10 times of measurement was made into carbon fiber strength (GPa). For evaluation, precursors immediately after production (within 7 days after production) and precursors stored at room temperature for 12 months after production were used.

[Example 1]

Amino-modified silicone A1, Bronsted acid compound B1, polyoxyethylene alkyl ether D1 and water were mixed and emulsified to obtain a non-volatile component composition of the treatment agent shown in Table 1, and the obtained amino-modified silicone aqueous emulsion was mixed with acetylene surfactant When C1 is added, the weight ratio of the amino-modified silicone A1 to the nonvolatile matter of the treatment agent is 80% by weight, the weight ratio of the Bronsted acid compound B1 is 0.7% by weight, the weight ratio of the acetylenic surfactant C1 is 2% by weight, The processing agent (precursor processing agent) whose weight ratio of polyoxyethylene alkyl ether D1 is 17.3 weight% was prepared. And the non-volatile matter concentration of the processing agent was 20 weight%.

Next, the adjusted processing agent was further diluted with water, and the processing liquid whose non-volatile matter concentration is 3.0 weight% was obtained.

The treatment solution is attached to the raw material acrylic fiber of the precursor obtained by copolymerizing 97 mol% of acrylonitrile and 3 mol% of itaconic acid, so that the imparting ratio is 1.0%, and the precursor is subjected to a stretching process (steam stretching, draw ratio 2.1 times). was produced (short fiber fineness 0.8 dtex, 24,000 filaments). This precursor was flame-resistant for 60 minutes in a flame-resistant furnace at 250° C., and then calcined in a carbonization furnace having a temperature gradient of 300 to 1,400° C. under a nitrogen atmosphere to convert to carbon fibers. Table 1 shows the evaluation result of each characteristic value.

[Examples 2 to 22, Comparative Examples 1 to 17]

Except having adjusted the processing liquid so that it might become a non-volatile matter composition of the processing agent shown in Tables 2-4 in Example 1, it carried out similarly to Example 1, and obtained the precursor and carbon fiber after processing agent adhesion. The evaluation result of each characteristic value is shown to Tables 1-4.

In addition, the detail of the non-volatile matter composition of Tables 1-4 is as follows.

<Amino-modified silicone (A)>

Amino-modified silicone A1 (25°C viscosity: 250 mm ² /s, amino equivalent: 7,600 g/mol, diamine type)

Amino-modified silicone A2 (25°C viscosity: 1,300 mm ² /s, amino equivalent: 1.700 g/mol, diamine type)

Amino-modified silicone A3 (25°C viscosity: 1,700 mm ² /s, amino equivalent: 3,800 g/mol, monoamine type)

Amino-modified silicone A4 (25°C viscosity: 20,000 mm ² /s, amino equivalent: 1,800 g/mol, diamine type)

Amino-modified silicone A5 (25°C viscosity: 1,500 mm ² /s, amino equivalent: 3,800 g/mol, diamine type)

<Bronsted acid compound (B)>

Carbonic acid compound B1: acetic acid

Carbonic acid compound B2: benzoic acid

Carbonic acid compound B3: Arginine

Carbonic acid compound B4: phosphoric acid

<Acetylene-based surfactant (C)>

Acetylene surfactant C1: 20 molar adduct of ethylene oxide of 2,4,7,9-tetramethyl-5-decyne-4,7-diol (in formula (4), R ³ and R ⁵ are all methyl groups, R ⁴ and R ⁶ are both an isobutyl group, R ⁷ is a hydrogen atom, AO is ethylene oxide, and n+m=20.)

Acetylene surfactant C2: 5 molar adduct of ethylene oxide of 2,4,7,9-tetramethyl-5-decyne-4,7-diol (in formula (4), R ³ and R ⁵ are all methyl groups, R ⁴ and R ⁶ are both an isobutyl group, R ⁷ is a hydrogen atom, AO is ethylene oxide, and n+m=5.)

Acetylene surfactant C3: 3,6-dimethyl-4-octyne-3,6-diol (in formula (2), R ³ , R ⁵ are all methyl groups, R ⁴ and R ⁶ are all ethyl groups, R ⁷ is hydrogen atom.)

Acetylene surfactant C4: 2,4,7,9-tetramethyl-5-decyne-4,7-diol (in formula (2), R ³ , R ⁵ are all methyl groups, R ⁴ , R ⁶ are both iso A butyl group, R ⁷ is a hydrogen atom.)

<Polyoxyalkylene alkyl ether (D)>

Polyoxyethylene alkyl ether D1: C12-14 alkyl ether to which 5 moles of oxyethylene groups were added

Polyoxyethylene alkyl ether D2: C12-14 alkyl ether to which 7 moles of oxyethylene groups were added

Polyoxyethylene alkyl ether D3: C12-14 alkyl ether to which 9 moles of oxyethylene groups were added

In addition, in Tables 1-4, the numerical value in parentheses of a Bronsted-acid compound (B) shows the molar equivalent of a Bronsted-acid compound (B) with respect to 1 mol of amino groups of an amino-modified silicone (A). In addition, the numerical value in parentheses of an acetylenic surfactant (C) shows the weight ratio of an acetylenic surfactant (C) when 100 weight part of amino-modified silicones (A) is used. In addition, the numerical values indicated in parentheses after storage of the strand hardness and carbon fiber strength show the rate of change with respect to the numerical values immediately after manufacture.

As is clear from Tables 1 to 4, the acrylic fiber treatment agent of Examples is for carbon fiber production, compared with the acrylic fiber treatment agent of Comparative Example which does not contain the Bronsted acid compound (B) and/or the acetylenic surfactant (C). It turns out that it is excellent in suppression of deterioration with time of an acrylic fiber.

The acrylic fiber processing agent of this invention is a processing agent used when manufacturing the acrylic fiber for carbon fiber manufacture, and in order to manufacture high-quality carbon fiber, it is useful. In the acrylic fiber for carbon fiber manufacture of this invention, the processing agent of this invention is processed, and it is useful in order to manufacture high-quality carbon fiber. High-quality carbon fibers can be obtained by the method for producing carbon fibers of the present invention.

Claims (11)

The processing agent for acrylic fibers containing an amino-modified silicone (A), a Bronsted-acid compound (B), and an acetylenic surfactant (C). According to claim 1,
The processing agent for acrylic fibers whose ratio of a Bronsted acid compound (B) is 0.01-2.5 molar equivalent with respect to 1 mol of amino groups of the said amino-modified silicone (A). 3. The method of claim 1 or 2,
The ratio of the said acetylenic surfactant (C) is 0.1-12 weight part with respect to 100 weight part of said amino-modified silicones (A), The processing agent for acrylic fibers. 3. The method of claim 1 or 2,
The acetylene-based surfactant (C) is selected from acetylene alcohol (C1), acetylenediol (C2), a compound (C3) in which an alkylene oxide is added to acetylene alcohol, and a compound (C4) in which an alkylene oxide is added to acetylene diol (C4) The processing agent for acrylic fibers which is at least 1 type. 5. The method of claim 4,
A compound (C3) wherein the acetylene alcohol (C1) is a compound represented by the following general formula (1), the acetylenediol (C2) is a compound represented by the following general formula (2), and an alkylene oxide is added to the acetylene alcohol (C3) It is a compound represented by this following General formula (3), The processing agent for acrylic fibers whose compound (C4) which added alkylene oxide to the said acetylenediol is a compound represented by following General formula (4).
[Formula 1]

(In Formula (1), R ¹ and R ² are each independently and an alkyl group having 1 to 8 carbon atoms.)
[Formula 2]

(In formula (2), R ³ , R ⁴ , R ⁵ and R ⁶ are each independently an alkyl group having 1 to 8 carbon atoms.)
[Formula 3]

(In formula (3), R ¹ and R ² are each independently an alkyl group having 1 to 8 carbon atoms. R ⁷ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. AO is an oxyalkylene group having 2 to 4 carbon atoms. Indicate, n is a number from 1 to 50.)
[Formula 4]

(In formula (4), R ³ , R ⁴ , R ⁵ and R ⁶ are each independently an alkyl group having 1 to 8 carbon atoms. R ⁷ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. A plurality of R ⁷ in ) may be the same or different. AO represents an oxyalkylene group having 2 to 4 carbon atoms. m and n are each independently and are a number from 1 to 50.) 3. The method of claim 1 or 2,
The processing agent for acrylic fibers whose weight ratio of the said amino-modified silicone (A) to the non-volatile matter of a processing agent is 40 to 95 weight%. 3. The method of claim 1 or 2,
The processing agent for acrylic fibers further containing polyoxyalkylene alkyl ether (D). 8. The method of claim 7,
The processing agent for acrylic fibers in which the said polyoxyalkylene alkyl ether (D) contains the compound represented by following General formula (5).
[Formula 5]

(In the general formula (5), R ⁸ represents an alkyl group having 6 to 22 carbon atoms. AO represents an oxyalkylene group having 2 to 4 carbon atoms. Each j is independent and is a number from 1 to 50.) 8. The method of claim 7,
The ratio of the total of the said acetylene-type surfactant (C) and the said polyoxyalkylene alkyl ether (D) with respect to 100 weight part of said amino-modified silicone (A) is 5-50 weight part, The processing agent for acrylic fibers. The acrylic fiber for carbon fiber manufacture formed by making the acrylic fiber processing agent of Claim 1 or 2 adhere to the raw material acrylic fiber of the acrylic fiber for carbon fiber manufacture. A spinning process of spinning by attaching the fiber treatment agent according to claim 1 or 2 to the raw acrylic fiber of acrylic fiber for carbon fiber production A method for producing carbon fibers, comprising a chlorination process and a carbonization process for carbonizing the flammable fiber in an inert atmosphere at 300 to 2,000°C.