JPS63238193A - Novel method for producing mesophase pitch for carbon fiber having high strength and modulus - Google Patents

Abstract

PURPOSE:To obtain the titled 100% mesophase pitch at a low cost, by removing a low volatile component having low molecular weight in petroleum based pitch which is a raw material in a production process. CONSTITUTION:A petroleum based pitch produced as a by-product in thermal cracking of desulfur reduced pressure light oil is distilled under reduced pressure and the distillate is subjected to heat treatment under nonoxidating atmosphere at 380-420 deg.C to provide a pitch containing 5-15% mesophase, which is then subjected to heat and aging under nonoxidating atmosphere at 300-350 deg.C to divide into (A) nonmesophase pitch of upper layer and (B) mesophase pitch of lower layer. Then raffinate nonmesophase pitch obtained by subjecting component (B) to extraction treatment with an aliphatic hydrocarbon solvent is subjected to heat treatment at 380-420 deg.C to provide a pitch containing 10-60% mesophase, which is subjected to heat aging under nonoxidating atmosphere at 300-350 deg.C to divide into (C) nonmesophase pitch of upper layer and (D) 100% mesophase pitch of lower layer and afford the aimed pitch.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses petroleum pitch (composition, H1 component, S. component, etc.) as a raw material to produce 100-column pitch (its composition, S. component, Q, 8. component, and Q). This study investigates and elucidates the production mechanism of mesophase glue that produces (component i.), and relates to a manufacturing method for obtaining 100% men-7A glue for melt spinning with stable physical properties and excellent properties.

[Conventional technology]

As a result of the rapid growth of the aircraft, automobile, and other transportation manufacturing industries in recent years, some of the physical properties of some of the materials are extremely superior, and their uniqueness is There is an increasing demand for materials that can exhibit high performance, and there is a strong demand for materials that have particularly high strength and elasticity, and at the same time are inexpensive in terms of number of wheels. In order to meet these demands, research into reinforced resins (composite materials) is being actively conducted.

One of the most promising materials for use in composite materials is long-fiber, high-strength, high-modulus carbon 31e fibers. This material only appeared at the beginning of the rapid growth of the aforementioned industries. When this charcoal jam is combined with a resin, it is possible to obtain a composite material that exhibits completely unprecedented properties.

It is a well-known fact that the raw materials for currently available high-strength, high-modulus carbon fibers are mainly polyacrylonitrile fibers produced using special manufacturing and spinning methods.However, this polyacrylonitrile fiber is expensive as a precursor. Unfortunately, the yield of carbon fiber from the precursor is extremely poor, about 45 cm. Therefore, J+7 acrylo-based (PAN-based) carbon fibers obtained from them are expensive.

As a method for manufacturing high-strength, high-modulus carbon fibers at low cost, a method for manufacturing high-strength, high-modulus carbon fibers using pitch containing mesophase as a raw material was proposed by Tokko Sho & 4-1.810.
It is a well-known fact that the material containing mesophase is a raw material for high-strength and high-modulus carbon fibers. However, this mesophase-containing pitch contains a large amount of non-meso phase and is not considered to be optimal as a raw material for high-strength, high-elasticity carbon flL fibers.

Also, Tokuko Sho 57-88.0%, H1 component about 2.0% in 6
B, componential 15.0% to about 4
5. A method for producing carbon fiber and fiber using Gitsuchi as a raw material, which contains OS, the remainder being benzene-insoluble matter, and about 90.0 or more mesophase, is described, and its physical properties are disclosed in Japanese Patent Publication No. 57-88.0. %, 6, but its physical properties are not at all high strength and high elasticity.

[The problem that the present invention attempts to solve]

The object of the present invention is to prepare a 100% mesophase pitch for melt spinning using components B, components, c2. ．． S. Ingredients and Q,
The composition of the raw petroleum pitch is H, as it is made from 1° component.
The column is composed of 00chi and B, components, and using these as a pace, H1 component. S. Ingredients, Q, 8. Ingredients and Q. i. By elucidating the formation mechanism of 100% mesophase pitch by changing the components, we have found that in order to remove H00 and stabilize the physical properties by the most rational means in the heating and aging process, for example, A small) 100 inch 7A pitch was obtained and used for melt spinning.

[Means to solve the problem]

As a method for producing stable 100% mesophase pitch with excellent physical properties and low cost for use in high-strength, ultra-high modulus carbon fibers, we use extremely cheap petroleum pitch (its composition is H00C and B, components) as a raw material to produce a stable 100% mesophase pitch with excellent physical properties. Stable and excellent 100
Based on the elucidation of the generation mechanism of % mesophase pitch, H0
100% for high-strength ultra-high modulus carbon fiber with 0-chi removed.
The objective is to rationally produce mesophase pitch.

The purpose is to conduct thermal catalytic cracking (F) of desulfurized vacuum gas oil.
Petroleum-based pitch (L component 20.0%) produced by CC)
〜84.0 Section. S. Ingredients 16.0% to 80.0%,
Q. i. Ingredients: 0.1% or less, this Q. i. The components are insoluble due to hydrogenation) and distilled under reduced pressure to 85 degrees centigrade (initial distillation 460°C to final distillation 560°C), and then blowing a non-oxidizing gas into the fraction and stirring at a constant temperature of 380°C to 420°C. Pitch containing 5% to 15% of mesophase (confirmed with a polarizing microscope) is produced by heat treatment for 4 to 10 hours under pressure or pressure, and the resulting pitch is heated under a stream of non-oxidizing gas at a temperature of 300°C to 350°C. Aging is carried out for 10 hours to 10 hours at '(:'), and only the mesophase in the pitch is fused and becomes large. Check.H
1 component io, o* to 17.0%, B, component 22.0
% to 46.0%, Q, 8. component 42.0% to 60.0ts%Q,i, component 0.5%, and (7)Q,i
.

component is soluble upon hydrogenation) and the lower layer mesophase pitch (
Q in petroleum pitch in this lower mesophase pitch
．． i. This upper layer of non-mesopitch is separated by solvent extraction with aliphatic hydrocarbons (hexane, heptane, octane, and mixtures thereof). The resulting raffinate is a non-mesopitch (H, component 1.0% or less. S. component 2
4.0% to 51.0%, Q. S. Ingredients: 46.0 chi to 72.0 yen, Q. i. (0.6% or less) is used as a precursor for melt-spinning pitch, and 100 parts of this precursor contains no mesophase, which is clearly separated as a by-product when producing 100% mesophase pitch for melt-spinning pitch. Non-mesopitch (confirmed with polarizing microscope. H0 component 0.
5 or less, B, component 22.0% to 35.0%,
Q. S. Ingredients 61.0% to 87.0%, Q. i. 0.4% → 4.0%) are mixed, non-oxidizing gas is blown into the mixture, and the temperature is 380°C to 420'C for 2 hours while stirring under normal pressure or increased pressure. Heat treatment is performed for 6 hours to produce a pitch containing 20 to 6 degrees of mesophase, and the resulting pitch is aged in a stream of non-oxidizing gas at a temperature of 300 to 350 degrees Celsius for 10 hours to 6 hours to remove the mesophase in the pitch. The upper layer is non-mesopitch (which contains no mesophase at all).
Confirmed using a polarizing microscope. H0 component 0.5 or less. S. Ingredients 22.0% to 35.0%, Q. S. Ingredients 61.0 to 87.0, Q. i. Ingredients 0.4% → 4.0%, Q.
i. Components are soluble by hydrogenation) and the lower layer 100% mesophase pitch (H0 component 0.10% or less. S. component 8.0
Chi to 21.0 chi, Q, S, ingredients 42.0% to 58.
0%, Q. i. component 28.0% to 45.0%, this Q. i. The components are soluble by hydrogenation, and the average molecular weight is 870 to 980), and are clearly separated depending on the difference in specific gravity, and the purified 100% mesophase pitch is provided for pitch for high strength and ultra high elasticity carbon fibers. It is to be. This 100% mesophase pitch has a softening point of 275'C to 295C and a viscosity of 200 poise to 320 poise at 320C.

B, component, and Q of the components of this 1004 mesophase
．． S. Ingredients and Q. i. Physical properties such as softening point and viscosity are determined by the ratio of the components, and the relationship between the ratio of each component and the physical properties cannot be separated at all. When the H0 component is removed, the V during melt spinning depends on the Volatile matter from the surface of the nozzle near the thread hole is reduced, and thread breakage is extremely reduced.

In the production of 100% mesophase pitch for long-fiber, high-strength, ultra-high elasticity carbon fibers, as a precursor for the first reaction in which petroleum-based pitch is heat-treated, and in the production of 1()0% men 7Aze pitch. Preferred processing conditions are a heating temperature of 390°C to 410'C and a heating time of 2 to 10 hours, and preferred aging and fusing conditions are a maturing temperature of 310°C.
to 330'C and aging time of 10 hours to 10 hours.

The non-oxidizing gases used in this cicada reaction are ethane, pro/
Butane, a distillate with a low boiling point that does not become heavy, and the most economical and rational gas is the dry gas that is produced as a by-product when heat-treating petroleum pitch (for example, water! 6.0%, methane). 74.6 thi, ethane 13.3%, pronoq 3.6%,
Butane 1.3%, pentane 0.9%, olefin approx. 0.
3%), etc.e The most distinctive feature of the present invention is that the distillation of petroleum pitch produced by thermal catalytic cracking (FCC) of desulfurized vacuum gas oil is reduced by 85% (composition H0 component). , B, component, etc.) are used as raw materials and heated and aged so that the ingredients of the husband are B, component, Q, 8. Ingredients and Q. i. Through the elucidation of the generation mechanism that produces Zoo 4-7 Aze pitch, in which the components mature and each component forms a stable combination, it is also possible to
By reducing the H8 component as much as possible, the H8 component that volatilizes from the spinning hole of the spinneret when melt-spinning 100q6 mesophasic pitch is almost eliminated. Since there is no contamination, it is possible to smoothly wind filament yarns for tens of hours or more with almost no yarn breakage using a melt spinning machine having several hundred sides and spinning holes of more than 100 sliver. Also carbon f produced from it
11t fiber exhibits extremely unique physical properties, for example, it can be easily expected that the strength will be 300 kg/Ha or more in the form of a strand, and the elastic modulus will be 70 T/g2 or more in the form of a strand.

Example 1 Petroleum pitch (H9 component 76.18%, B. component 23.8%) produced by thermal catalytic cracking (FCC) of desulfurized vacuum gas oil
2%, Q. i. The fraction (initial distillation: 460°C to final distillation: 560°C) obtained by distilling under reduced pressure 0.1% or less of the components (less than 0.1%), and then blowing propane gas into the fraction (initial distillation: 460°C to final distillation: 560°C), stirring, and heating at a temperature of 400°C for 6 hours to remove the menphase. A pitch containing 10% of carbon dioxide was produced, and the resulting pitch was heated to a temperature of 32°C under a gas flow of professional gas.
The mesophase in the pitch is aged at 0°C for a period of time to fuse and become gigantic, and at that aging temperature, the upper layer of non-mesopitch containing no mesophase (H0 content 11.34%.S.
Ingredients 42.42%, q, 8. Ingredients: 45.86%, Q. i
．． Ingredient 0.38%, this Q. i. When hydrogenated with lithium, the components were clearly separated into lithium (all soluble in solvents) and the lower layer meso-7A based on the difference in specific gravity. Stone 1' [Q.
i. It was possible to remove components and inorganic substances by including them.

Next, in the upper layer, non-mesopitch (H0 component 0.05%, B. component 47.84%, Q,
S, component 51.72, Q. i. Ingredients 0.42%) 10
Non-mesopitch (H9 component 0.20%
Below, B.

Ingredients: 33.08, Q. S. Ingredient 66.23, Q. i
．． Ingredient 0.50%, this Q. i. 100 parts of the ingredients are soluble in a solvent when hydrogenated (depending on lithium), and the mixture is heated at 400°C for 2 hours while blowing non-oxidizing gas and stirring to dissolve 45% of the menphase. This produced pitch is immediately aged at a temperature of 320°C under a flow of non-oxidizing gas, and only the menphase in the pitch is fused to a large size. Non-mesopitch (L component 0.20 or less, S. component 33.08%, Q.S. component 66.23%, Q.i. component 0.50%) and the lower layer 10
0% mesophase pitch (L component trace. S. component 18.
88%,Q,,8. Ingredients 48.74%, Q. i. Ingredient 3
2, 37, and average molecular weight 920) were clearly separated and purified based on the difference in specific gravity.

The conversion point of this 100% mesophase pitch is 283
°C1 viscosity is 210 poise at 320 °C, and 10
Non-meso pitch containing no mesophase (H1 component 0.02%) used when manufacturing 0% mesophase pitch
．． S. Component 33.08, Q, , S, component 66.23, Q. i. When producing 100% mesophase pitch (component 0.50%), non-meso pitch containing no mesophase can be used, which clearly separates into the upper layer due to the difference in specific gravity.

Using this 100% mesophase pitch as a raw material and using a melt spinning machine equipped with hundreds of spinning holes, it has become possible to produce long fiber pitch fibers extremely smoothly and without yarn breakage. 2,000 long fiber pitch fibers obtained (2K)
The strands were bundled and made infusible at 320℃ in air, then fired and carbonized in an inert gas, and then graphitized at 2.600℃ in argon gas, with a strength of 320 Kg/m'' in strands and an elastic modulus of We were able to create a high-strength, ultra-high modulus carbon fiber bundle with long fibers of 76T/tension from the strands.

[Effects of the present invention]

Made by preliminary petroleum-based pitch made by thermal catalytic cracking (FCC) of desulfurized vacuum gas oil. Made by solvent extraction of non-mesopitch that does not contain any mesophase. Made from non-mesopitch that does not contain H9 components as a raw material. By melt-spinning mesophase pitch, carbon fibers with excellent spinnability and extremely excellent physical properties can be produced.

Claims (1)

[Claims] 1) H. Ingredients: 150cc of heptane from 10g of sample
Ingredients extracted at a temperature of 98.4℃. B. Ingredients: H. H obtained by solvent extraction of the components
．． Component extracted from insoluble matter using 150 cc of benzene at a temperature of 80.1°C. Q. S. Ingredients: B. B. obtained by solvent extraction of the components. A component extracted from insoluble matter using 150 cc of quinoline at a temperature of 237°C. Q. i. Ingredients: Q. S. Defined as the insoluble matter obtained by solvent extraction of components, thermal catalytic cracking (FCC) of desulfurized vacuum gas oil is used to produce mesophase pitch of long-fiber, high-strength, ultra-high modulus carbon fiber.
) as a by-product of petroleum pitch (H. component 20.0% to 84.0%, B. component 16.0% to 84.0%, Q
．． i. Ingredients 0.1% or less, this Q. i. The components are insoluble even when hydrogenated) and are distilled under reduced pressure to obtain a fraction cut by 85% (initial distillation 460℃ to final distillation 560℃ average molecular weight 355 to 400).
) is heated with stirring at a heating temperature of 380°C to 420°C for 2 to 10 hours while blowing a non-oxidizing gas into it to produce pitch containing 5% to 15% mesophase, and the resulting pitch is aged. Temperature 300℃~350℃
The pitch is aged for 10 to 30 hours under a stream of non-oxidizing gas to fuse only the mesophase in the pitch to a large size. % to 17.0%, B. component 22.0% to 46.0%, Q.S. component 42.0% to 60.0%, Q.i. component 0.5%, this Q.i. The non-mesopitch components in the upper layer are separated into aliphatic hydrocarbons (hexane, heptane, octane,
So-called raffinate non-mesopitch (H. component 1.0% or less, B. component 24.0% to 51.0%, Q.S. component 46.0%) obtained by solvent extraction of
to 72.0%, Q. i. Ingredients 0.6% or less, this Q.
i. 100% mesophase pitch for melt spinning (components soluble by hydrogenation) was used as a precursor of 100% mesophase pitch for melt spinning, and this was heated to a temperature of 380°C to 380°C while stirring while blowing non-oxidizing gas under normal pressure or pressure. Pitch containing 10% to 60% of mesophase is produced by heat treatment at 420°C for 2 to 6 hours, and the resulting pitch is heated at 3°C under a flow of non-oxidizing gas.
Aged at 00°C to 350°C for 10 to 30 hours to fuse and enlarge only the mesophase in the pitch, and at that aging temperature the upper layer, non-mesopitch containing no mesophase at all (H. component 0.5% or less, B .Ingredients 22.0% to 35
．． 0%, Q. S. Ingredients 61.0% to 87.0%, Q.
i. Ingredients 0.4% → 4.0%, this Q. i. component is soluble by hydrogenation) and the lower layer 100% mesophase pitch (H
．． Ingredients 0.10% or less, B. Ingredients 8.0% to 21.0
%, Q. S. Ingredients 42.0% to 58.0%, Q. i.
Ingredients 28.0% to 45.0%, this Q. i. A method for purifying pitch for melt spinning, characterized in that the components are soluble by hydrogenation, are clearly separated depending on the difference in average molecular weight (870 to 980), and are obtained as 100% mesophase pitch. 2) So-called raffinate non-mesopitch (H. component 1.0% or less, B. component 24.0% to 51.0%) obtained by solvent extraction of aliphatic hydrocarbons produced by the production method of claim 1 0%, Q.S. component 46.0% to 72.0%
,Q. i. Ingredients 0.6% or less, this Q. i. Components are soluble by hydrogenation) per 100 parts of non-mesopitch (H. component 0.5% or less, B. component 22.0 % to 35.0%, Q.S. component 61.0% to 87.0%,
Q. i. Ingredients 0.4% → 4.0%, this Q. i. Mix 60 to 140 parts of ingredients (components soluble by hydrogenation), blow non-oxidizing gas into the mixture, stir under normal pressure or pressurization, and heat treat at a temperature of 380°C to 420°C for 2 hours. Then, a pitch containing 20% to 60% mesophase is produced, and the resulting pitch is heated at a temperature of 300°C to 300°C under a flow of non-oxidizing gas.
Aging is performed at 50°C for 10 to 30 hours to fuse only the mesophase in the pitch to a large size. 22.0% to 35.0%, Q
．． S. Ingredients 61.0% to 87.0%, Q. i. Ingredient 0
．． 4% → 4.0%, this Q. i. component is soluble by hydrogenation) and the lower layer 100% mesophase pitch (H. component 0.
10%, B. Ingredients 8.0% to 21.0%, Q. S. Ingredients 42.0% to 58.0%, Q. i. Ingredients 28.0%
to 45.0%, this Q. i. Ingredients are soluble by hydrogenation,
1. A purification method according to claim 1, which obtains 100% mesophase pitch which is distinctly classified and separated into 100% mesophase pitch based on the difference in specific gravity (average molecular weight 870 to 980).