JPH02311529A - Metal-containing aromatic polycyclic polymer and its preparation - Google Patents

Abstract

PURPOSE:To improve the mechanical properties and resistance to oxidation, abrasion, and heat by thermally reacting and/or thermally melting a specific random copolymer with an arom. polycyclic compd. CONSTITUTION:100 pts.wt. random copolymer (A) comprising a transition metal-contg. organosilicon polymer and an arom. polycyclic compd. consisting of a thermally treated petroleum- or coal-derived pitch, wherein Si atoms of said organosilicon polymer are bonded at least partially to C atoms on arom. rings of said polycyclic compd. through Si-C linkage, and 50 to 20000 pts.wt. optically isotropic arom. polycyclic compd. (B) contg. a latent anisotropy-forming component are thermally reacted and/or thermally melted at 200 to 500 deg.C. Said organosilicon polymer mainly comprises a bonding unit, Si-CH2, or said bonding unit and another bonding unit, Si-Si, contains H, a lower alkyl, phenyl or silyl group as a side chain attached to Si, and contains at least one metal selected from the group consisting of Ti, Zr, and Hf bonded directly or through an oxygen atom to at least a part of Si atoms in said bonding units in the main polymer chain. Said arom. compd. (B) is obtd. by thermally treating a petroleum- or coal-derived pitch to give a mesophase-contg. pitch, hydrogenating and thermally treating the resulting pitch.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention provides an inorganic fiber with excellent mechanical properties, oxidation resistance, and compatibility with a matrix for composite materials;
The present invention relates to a precursor polymer suitable for producing matrices for composite materials, molded articles, etc. with excellent oxidation resistance, abrasion resistance, heat resistance, etc., and a method for producing the same.

(Conventional technology and its problems) Carbon fiber is lightweight, has high strength and high elasticity,
It is being used in a wide range of fields, including sports and leisure goods, aircraft, bicycles, and building materials.

As carbon fibers, PAN-based carbon fibers made from polyacrylonitrile and so-called pitch-based carbon fibers made from petroleum-based and coal-based pitches are known.

Pitch-based carbon fibers are generally inferior in strength to PAN-based carbon fibers, but since the raw materials are cheap, various studies have been conducted on ways to increase the strength.
No. 223316 discloses a method for effectively generating mesophase and orienting it during spinning.

However, since carbon fibers are basically crystalline fibers, they are hard, tend to fluff, and have poor wettability with a matrix when used as a composite material.

Therefore, various methods for surface treatment of carbon fibers have been proposed, and the currently known methods use materials such as polyvinyl alcohol, unsaturated polyester resins, and epoxy resins for the purpose of imparting flexibility to the fibers and suppressing the generation of fuzz. There are methods such as applying a suitable sizing agent to the surface, and dry or wet oxidation treatment of the surface for the purpose of improving adhesion to the matrix.

Among these treatments, the method of providing a surface oxidation layer in particular damages the fibers during oxidation, so that physical properties tend to deteriorate. Furthermore, carbon fiber cannot be used in an oxidizing atmosphere at a temperature exceeding 500°C because it will burn.

Against this background, we are developing a new fiber that has high strength and high modulus, has good wettability and adhesion with the matrix, and is cheaper than the PAN-based carbon fiber that has been used in a wide range of fields. has been strongly requested.

Furthermore, it is strongly desired in various fields to improve the oxidation resistance of carbon fibers at higher temperatures.

On the other hand, so-called C/C composites and carbon molded bodies that use carbon fiber as the reinforcing fiber and carbon as the inorganic matrix have excellent specific strength, specific elasticity, heat resistance in a non-oxidizing atmosphere, toughness, and friction properties, and are heat resistant. It is promising as a structural material and brake material.

However, since the matrix of C/C composites and carbon molded bodies consists only of carbon, it is difficult to use them for long periods in an oxidizing atmosphere, and although they have excellent friction properties and lubricity, Abrasion resistance is not necessarily sufficient, and further improvement in mechanical properties is expected.

As a method for solving the problems with the fibers, for example, Japanese Patent Application Laid-Open No. 62-209139 and Japanese Patent Application Laid-Open No. 62-21
No. 5016 discloses that organoboriarylsilane is synthesized by mixing and heating an organic solvent-soluble component in coal-based or petroleum-based pitch and polysilane, and then it is spun, infusible, and fired to form silicon carbide fibers and carbon. A method for producing inorganic fibers with properties intermediate to that of fibers is described.

However, in the above method, pitch, which does not contain any organic solvent insoluble matter, is selected as one of the starting materials, and the reaction is carried out under conditions in which the insoluble matter is not produced at all in the production of organoboriarylsilane.

That is, the spinning raw material that is the obtained product does not contain an oriented component that is essential for developing the strength of carbon fibers, and high elasticity inorganic fibers are not obtained from the spinning raw material.

Furthermore, the method disclosed in the above-mentioned publication has the problem that as the pitch component increases, the heat resistance in an inert gas improves, but the oxidation resistance decreases, and furthermore, the mechanical properties deteriorate significantly.

In addition, as a method of compensating for the woody defects of the carbon matrix, Am, Ceram, Soc, Bull, 6
2 (1983) 916, Walker (B.E.
Walker, Jr.) have described a method in which a C/C composite is impregnated with an organosilicon polymer and then thermally decomposed to introduce silicon carbide components into the matrix. The strength is low at 158MP.

Also, Proc, of Int, Symp, on C
eramic+compon.

for Engine, 1983+Japan, p50
In 5, Fitzer et al.
C/(, I describes a method in which silicon melt is impregnated into the ingot and the matrix is made into silicon carbide. However, the resulting composite material is made up of metal silicon remaining unreacted between the matrix particles. Therefore, creep metamorphosis occurs at high temperatures of 1300″C or higher, and it does not have the high-temperature properties of C/C composites.

In addition to the conventional complicated C/C composite manufacturing process, each of the above-mentioned processes involves an additional complicated process, making it difficult to use industrially.

Therefore, there is a strong demand for the development of precursor polymers that can be easily converted into excellent carbonaceous inorganic fibers, matrices for composite materials, etc. by mineralization.

(Means for Solving the Problems) An object of the present invention is to provide inorganic fibers with excellent mechanical properties, oxidation resistance, and compatibility with matrix for composite materials; It is an object of the present invention to provide a precursor polymer which solves the above-mentioned problems and is suitable for the production of matrixes for composite materials, molded articles, etc., which have excellent heat resistance, etc., and a method for producing the same.

According to the present invention, (A) mainly consists of a bonding unit (S i CHz ) or a bonding unit (S i CHz ) and a bonding unit (Si--Si), and has a hydrogen atom or a lower alkyl group in the side chain of a silicon atom. , a substituent selected from the group consisting of a phenyl group and a silyl group, and at least one type of atom selected from the group consisting of titanium, zirconium and hafnium directly or via an oxygen atom, at least one of the silicon atoms. (B) an optically isotropic polycyclic aromatic compound unit containing a potential anisotropy-forming component; At least some of the silicon atoms are
There is provided a metal-containing polycyclic aromatic polymer characterized in that the metal-containing polycyclic aromatic polymer is bonded to the carbon atom of the aromatic ring (B).

Furthermore, according to the invention, l) a bonding unit (SiCH2) or a bonding unit (S i
-CH,) and a bonding unit (Si-Si), and has a hydrogen atom, a lower alkyl group, a phenyl group, or a silyl group in the side chain of a silicon atom, and has a silicon atom in the main skeleton consisting of the above bonding units. , titanium, zirconium, and hafnium, are bonded directly or via oxygen atoms to at least a portion of the silicon atoms of the transition metal-containing organosilicon polymer. (2) a random copolymer in which a portion of petroleum-based pitch or a heat-treated product thereof is bonded to the carbon of the aromatic ring of a polycyclic aromatic compound via a silicon-carbon linking group; and 2) petroleum-based pitch. An optically isotropic polycyclic aromatic compound containing a potential anisotropy-forming component obtained by heat-treating a mesophase-containing pitch obtained by heat-treating a mesophase-based pitch or a coal-based pitch and then heat-treating it again. Provided is a method for producing a metal-containing polycyclic aromatic polymer, which comprises heating-reacting and/or heating-melting at a temperature in the range of 200 to 500°C.

First, the metal-containing polycyclic aromatic polymer of the present invention will be explained. In the following description, all "parts" are "parts by weight" and are percentages (%) as a unit of component content.
are all weight %.

The metal-containing polycyclic aromatic polymer (4) of the present invention consists of components (A) and (B), and at least a part of the silicon atoms of component (A) are aromatic atoms of component (B). Bonded to a carbon atom in the ring. Constituent component (A) and constituent component CB)
It is preferable that the weight ratio is 1:0.5 to 200.

The weight ratio of component (A) and component (B) is 0.5
If it is less than this, the oriented component in the metal-containing polycyclic aromatic polymer (4) will be insufficient, and for example, even if inorganic fibers are produced from this polymer, only those with low strength and elastic modulus will be obtained.

In addition, when the above ratio exceeds 200, due to the lack of organosilicon component in the metal-containing polycyclic aromatic polymer (4),
The oxidation resistance of the inorganic compound of this polymer decreases, and the wettability with plastics etc. decreases.

The metal-containing polycyclic aromatic polymer (4) of the present invention contains 0.25 to 30% of silicon atoms, has a weight average molecular weight of 200 to 11,000, and a melting point of 220 to 320°C. When the silicon atom content in the metal-containing polycyclic aromatic polymer (4) is less than 0.25%, the amount of an amorphous phase consisting of St, C, and O or β-SiC ultrafine particles in the inorganic product of the polymer For example, if the amount exceeds 30%, a highly elastic, non-oxidizing atmosphere due to the orientation of the ultrafine graphite crystals in the mineral compound is required. It is not possible to improve the heat resistance inside.

Metal-containing polycyclic aromatic polymers (4) with a weight average molecular weight lower than 200 do not substantially contain any orienting components, and therefore cannot provide high-performance inorganic fibers, composite materials, or molded bodies. , 11,000, the melting point is high and the fluidity is poor, making it difficult to mold into any shape.

Melting point of metal-containing polycyclic aromatic polymer (4) is 220°C
If it is lower than that, it does not substantially contain any orienting components, and when this polymer is spun to produce inorganic fibers, the precursor yarn is easily fused during infusibility and is a fired yarn with high strength and elastic modulus. cannot be obtained.

On the other hand, if the melting point of the above polymer is higher than 320°C,
Once the softening/flowing zone reaches a high temperature, the polymer may decompose, which is undesirable.

Further, the metal-containing polycyclic aromatic polymer (4) contains 0.05 to 10% of M (M is at least one element selected from Ti, Zr, and Hf) in addition to silicon atoms. . The mineralized product of the polymer has better mechanical properties and compatibility with other matrices because it contains M.

If the content of M is less than 5% of O, Q O, the above characteristics are hardly exhibited, and if it exceeds 10%, highly crosslinked high melting point substances and unreacted MX4 are mixed in the polymer. This makes it extremely difficult to perform melt spinning using the polymer as a dope, and also has a negative effect on molding due to foaming during heating.

Since the metal-containing polycyclic aromatic polymer (4) softens and flows at a relatively low temperature of 320''C or less, it is suitably used, for example, as a precursor for inorganic fibers.

Next, the manufacturing method of the present invention will be explained.

First, a precursor polymer (1) is prepared by heating and reacting an organosilicon polymer and pitch in an inert gas, preferably at a temperature in the range of 250 to 500°C.

The organosilicon polymer, which is one of the raw materials, can be synthesized by a known method. For example, polydimethylsilane obtained by the reaction of dimethyldichlorosilane and metallic sodium is heated to 400°C or higher in an inert gas. It can be obtained by

The organosilicon polymer has a bonding unit (Si CH2),
Or the bonding unit (Si 'CHz) and the bonding unit (Si 'CHz)
--Si), and the bonding unit (Si-CH,
) to the total number of bonding units (Si--32) is 1
: Within the range of 0 to 20.

The weight average molecule 1 (MW) of the organosilicon polymer is generally 300 to 1000, and those with Ml of 400 to 800 are used as intermediate raw materials for obtaining excellent inorganic fibers, composite materials, molded objects, etc. Particularly preferred for preparing certain random copolymers (2).

Another starting material, a polycyclic aromatic compound, is pitch obtained from petroleum and/or coal, especially heavy oil obtained by fluid catalytic cracking of petroleum, and pitch obtained by distilling the heavy oil. Distillate components or residual oils and pitch obtained by heat-treating them. There are no particular restrictions on the source of raw oil and/or raw coal and the properties and physical properties of the pitch obtained, but the final product, the metal-containing polycyclic aromatic polymer (4), can be used as a raw material dope for producing inorganic fibers. When used, in particular, it contains 5 to 98% by weight of components insoluble in organic solvents such as benzene, toluene, xylene, and tetrahydrofuran, and has a weight average molecular weight (M-) of 300 to 300.
0 and a melting point gaff of 0 to 200°C is preferred. The weight average molecular weight is a value determined as follows.

That is, if the pitch does not contain organic solvent insoluble components for gel permeation chromatography (GPC) measurement, such as benzene, toluene, xylene, tetrahydrofuran, chloroform, and dichlorobenzene, the pitch is directly measured by GPC, and the pitch is determined from the above organic solvent insoluble components. If it contains
Hydrogenation is performed under mild conditions to convert the organic solvent-insoluble components into the organic solvent-soluble components, followed by GPC measurement. (The weight average molecular weight of the polymer containing organic solvent insoluble matter is the value obtained by performing the same treatment as above).

The proportion of pitch used is 2 per 100 parts of organosilicon polymer.
It is preferable that it is 1900 parts. If the proportion of the pitch component used is too small, the organic silicon component will increase,
Compatibility with mesophase polycyclic aromatic compounds deteriorates,
Uniformity during melting is impaired, and when a fiber molded article is produced, the elastic modulus is reduced. Furthermore, if the proportion is too high, the organosilicon polymer component is too small, resulting in decreased matrix wettability and oxidation resistance in the composite material produced from the polymer of the present invention.

If the reaction temperature of the above reaction is too low, it will be difficult to form bonds between silicon atoms and aromatic carbon, and if the reaction temperature is too high, the resulting precursor polymer (1) will be violently decomposed and its molecular weight will increase. Undesirable. The precursor polymer (1
) includes copolymers in which an organosilicon polymer and pitch are bonded via a silicon-carbon linking group, as well as polycondensates of the organosilicon polymer and pitch.

As the inert gas, nitrogen, argon, etc. are preferably used.

Next, the random copolymer (2) is prepared by reacting the precursor polymer (1) with a transition metal compound represented by the formula MX at a temperature of 100 to 500°C. Said M x 4
In the above, X may be one that can bond M to the silicon of the precursor polymer (1) directly or via an oxygen atom through condensation, and is not particularly limited, but may be a halogen atom, an alkoxy group, or a β-diketone. Complex-forming groups such as are preferred.

If the reaction temperature is too low, the precursor polymer (]) and NiMX4
If the condensation reaction with M does not proceed and the reaction temperature is excessively high, M
The crosslinking reaction of the precursor polymer (1) via Random copolymer (2), which is an intermediate raw material for obtaining excellent inorganic fibers, composite materials, and molded articles, cannot be obtained. −
For example, if M is Ti and X is QC, I (,
A suitable reaction temperature is 200-400'C.

Through this reaction, a random copolymer (2) in which at least some of the silicon atoms of the precursor polymer (1) are bonded to the metal M directly or via oxygen atoms is prepared. metal M
is -MX at the silicon atom of the precursor polymer (1).

Alternatively, they may be bonded in a side chain form in a bonding mode such as -0-MX, or may be bonded in a bonding mode in which the silicon atoms of the precursor polymer (1) are crosslinked directly or via oxygen.

As a method for preparing the random copolymer (2), in addition to the above-mentioned method, it is also possible to prepare the random copolymer (2) by reacting an organosilicon polymer with M X a and further reacting the resulting product with pitch. be.

Random copolymer (2) and an optically isotropic polycyclic aromatic compound containing a potential anisotropy-forming component (hereinafter, this may be simply referred to as "polycyclic aromatic compound (3)") .)
A metal-containing polycyclic aromatic polymer (4) is prepared by heating reaction and/or heating melting at 200 to 500°C.

The polycyclic aromatic compound (3) is, for example, a pitch obtained by removing the light fraction from the FCC slurry oil.
Optically anisotropic mesophase pitch obtained by a method of heat treatment at 00 to 500 ° C., the mesophase contained therein is substantially changed to a quinoline-soluble component,
It can be obtained by hydrogenating until the entire pitch forms an optically isotropic homogeneous phase. As the hydrogenation method, various conventionally known methods employed for hydrogenation to aromatic nuclei can be used, such as reduction methods using alkali metals, alkaline earth metals, and their compounds, electrolysis, etc. Reduction method, homogeneous hydrogenation method using complex catalysts, etc., heterogeneous hydrogenation method using solid catalyst, hydrogenation method using hydrogen pressure without catalyst, hydrogenation method using hydrogen donor such as tetralin etc.

Hydrogenation conditions vary depending on the method used, but 400
It can be carried out at a temperature of 0.degree. C. or less and a pressure of 200 atmospheres or less. The purpose of the present invention is not hindered in any way by heating and maintaining the obtained hydrogenated pitch in a molten state in order to improve its thermal stability.

The heating temperature in this case is above the melting temperature and 450 degrees Celsius.
The following are preferred. Generating a large amount of new mesophase by high-temperature heating increases the softening point, which is not preferable.

The polycyclic aromatic compound (3) obtained by the above method is generally a quinoline-soluble pitch having a melting point in the range of 200 to 300°C and a weight average molecular weight of 200 to 6,000.

The term "potential anisotropy" as used herein refers to anisotropy caused by molecules being oriented in the direction of the external force when an external force such as a shearing force or a stretching force is applied.

For example, if this pitch is used and subjected to spinning, infusibility, and sintering according to a conventional method for producing pitch-based carbon fibers, fibers with orientation in the fiber axis direction can be obtained.

The proportion of the polycyclic aromatic compound (3) used is preferably 5 to 900 parts per 100 parts of the random copolymer (2), and if it is less than 5 parts, the resulting polymer may potentially have orientation properties. Due to the insufficient silicon component content, even if the obtained polymer is mineralized, highly elastic fibers or molded articles cannot be obtained.If the content is more than 900 parts, the wetting of the matrix is insufficient due to the lack of silicon components. Fibers with excellent properties and molded articles with improved oxidation resistance cannot be obtained.

If the above-mentioned melt mixing temperature is lower than 200°C, an infusible portion will occur and the system will become non-uniform;
If the temperature is higher than this, the condensation reaction proceeds rapidly, the resulting polymer has a high melting point, and its fluidity is lost.

As a method for preparing the metal-containing polycyclic aromatic polymer (4), in addition to the above-mentioned method, an organosilicon polymer and pitch are reacted, and the resulting product is reacted with the polycyclic aromatic compound (3) and MX. It is also possible to prepare by adding , simultaneously or sequentially, and further reacting.

(Effect) The metal-containing polycyclic aromatic polymer (4) according to the present invention contains a transition metal-containing organosilicon copolymer and a potential anisotropy-forming component in the polymer, so this polymer can be melt-spun. , amorphous and/or β consisting of Si, M, C and 0 on ultrafine graphite crystals by infusibility and firing.
-SiC, MC1β-Solid solution of SiC and MC, and MC
, -x (0<X<1) and amorphous Sin, (0<y≦2) and M Og (0<z≦
It is possible to obtain a carbon-based inorganic fiber having a structure in which aggregates consisting of 2) are dispersed, which has high strength and high elasticity, and has excellent wettability with plastics. As described above, since there has not been a fiber that can satisfy both mechanical properties and wettability with plastics, there are great expectations for the development of applications, especially for FRP.

Furthermore, the fibers obtained from the polymer of the present invention can be used in high-temperature oxidizing atmospheres for carbon fibers, and can be made into oxidation-resistant carbon-based materials and fiber-reinforced ceramics by molding the polymer of the present invention. (FRC) matrix, etc. Further, the present invention greatly contributes from the viewpoint of effective use of pitch.

(Example) The present invention will be explained below with reference to Examples.

Reference Example 1 (Production method of organosilicon polymer) 5! 2.52 g of anhydrous xylene and 400 g of sodium were placed in a three-ring flask, heated under a nitrogen gas stream to the boiling point of xylene, and dimethyldichlorosilane 11 was added dropwise over 1 hour. After the dropwise addition was completed, the mixture was heated under reflux for 10 hours to form a precipitate. The precipitate was filtered and washed with methanol and then water to obtain 420 g of white powder polydimethylsilane.

400 g of this polydimethylsilane was charged into 32 three-hole flasks equipped with a gas inlet tube, a stirrer, a condenser, and a distillation tube, and heated at 420 degrees under a nitrogen flow of 50 m/min while stirring.
C. to obtain 350 g of a colorless and transparent slightly viscous liquid in a distillation receiver.

The number average molecular weight of this liquid was 470 as measured by thin pressure osmosis method.

When the infrared absorption spectrum of this substance was measured, it was found that 6
SiC on 50~900cm-' and 1250CI11-'
H: absorption of l, absorption of 5t-H at 2100 cm-', 1
5i-CHz- around 020cl' and 1355cm-'
Absorption of Si, C at 2900 cm-' and 2950 cm-'
-H absorption was observed, and the far-infrared rays of this substance The liquid material mainly consists of (Si CHz) bond units and (Si-32) bond units, and has hydrogen atoms and methyl groups in the silicon side chain. It turned out to be an organosilicon polymer.

According to the measurement results of nuclear magnetic resonance analysis and infrared absorption analysis, the ratio of the total number of (Si-CH2) bond units to the total number of (Si-32) bond units in this organosilicon polymer is approximately 1:3.
It was confirmed that the polymer was

300 g of the above organosilicon polymer was treated with ethanol to remove low molecular weight substances to obtain 40 g of a polymer having a number average molecular weight of 1200.

When the infrared absorption spectrum of this substance was measured, absorption peaks similar to those above were observed, and this substance mainly consists of (Si-CH2) bond units and (Si-Si) bond units, and has hydrogen atoms in the side chains of silicon. It turned out to be an organosilicon polymer having methyl groups.

According to the measurement results of nuclear magnetic resonance analysis and infrared absorption analysis, this organosilicon polymer is a polymer in which the ratio of the total number of (Si CH2) bond units to the total number of (Si-Si) bond units is approximately 7:1. This was confirmed.

Reference Example 2 (Production method for F'CC slurry oil) Among petroleum fractions, substances with a boiling point higher than that of light oil are subjected to fluid catalytic cracking and precision at a temperature of 500°C in the presence of a silica/alumina cracking catalyst. A residue was obtained from the bottom of the tower. This residue will be sent to FCC below.
It is called slurry oil.

As a result of elemental analysis, this FCC slurry oil had an atomic ratio of carbon atoms to hydrogen atoms (C/H) of 0.75, and an aromatic carbon ratio of 0.55 as determined by nuclear magnetic resonance analysis.

Example 1 (First step) 500 g of the FCC slurry oil obtained in Reference Example 2 was heated to 450°C under a nitrogen gas flow, and after distilling off the distillate at the same temperature, the residue was heated at 200°C. It was filtered to remove the infusible portion at the same temperature to obtain 225 g of light bone-removed pitch.

This light bone removal pitch was an optically isotropic pitch containing 75% xylene insolubles.

21 of the organic silicon polymer obtained in Reference Example 1 was added to 49 g of this pitch.
g and 20 g of xylene were added, the temperature was raised while stirring, and after the xylene was distilled off, the reaction was carried out at 400° C. for 6 hours to obtain 39 g of a precursor polymer.

As a result of infrared absorption spectrum measurement, the precursor polymer (1) was found to be
5t-H bond (IR: 2
100 cm-') and the formation of new 5t-C (benzene ring carbon) bonds (I R: 1135 cm-'), it is clear that some of the silicon atoms in the organosilicon polymer are polycyclic aromatic rings. It was found that it is a polymer that has a part directly bonded to.

(Second step) Tetraoctoxytitanium (T
i (QCs H1?) a) Add 2.75 g of xylene solution (11 g of 25% xylene solution), and after distilling off the xylene, react at 340'C for 2 hours to obtain 38 g of random copolymer (2). Ta.

This polymer contained no xylene-insoluble parts, had a weight average molecular weight of 1650, and a melting point of 272°C.

(Third step) 400 g of the FCC slurry oil obtained in Reference Example 2 was heated to 420°C under a nitrogen gas stream, the distillate at the same temperature was distilled off, and the residue was filtered while hot at 150°C. After removing the infusible portion at the same temperature, polycondensation was carried out at 400'C for 9 hours under a nitrogen stream without removing light components generated by the reaction, to obtain 75 g of heat-treated pitch. This heat-treated pitch has a melting point of 275°C, a softening point of 305°C, and contains 96% of xylene-insoluble matter and 25% of quinoline-soluble matter, and its optical anisotropy was observed by polarizing microscope observation of the polished surface. It was 95% mesophase pitch.

Using this mesophase pitch as a nickel-cobalt solid catalyst with zeolite as a carrier, 360°C1 hydrogen pressure 1
00) cg/c1n'' for 1 hour.

The hydrogenated product did not contain any quinolinated components, and observation of the polished surface with a polarizing microscope revealed that it was an optically isotropic pitch. This pitch was thermally stabilized by holding it at 400° C. for 30 minutes under a nitrogen stream to obtain a polycyclic aromatic polymer (3). The obtained polycyclic aromatic polymer (3) was an optically isotropic pitch with a melting point of 230° C. and a softening point of 238° C. without containing a quinolinated component. However, this polycyclic aromatic polymer (3) was made into a fibrous form using a capillary with a diameter of 0.5 mm, made infusible at 300°C in air, then fired at 1000°C in a nitrogen stream, and its cross section was observed. As a result, orientation in the fiber axis direction was confirmed, and it was found that the pitch was potentially anisotropic.

(4th step) Random copolymer (2) obtained in the 2nd step 40 g
and 80 g of polycyclic aromatic polymer (3) obtained in the third step.
were melt-mixed for 1 hour at 350''C under a nitrogen atmosphere to obtain a metal-containing polycyclic aromatic polymer (4) in a uniform state.

This metal-containing polycyclic aromatic polymer (4) is an optically isotropic polymer that does not contain any quinoline-soluble matter and has a xylene-insoluble matter of 38%, and has a melting point of 248°C and a softening point of 27
It was 0°C. In addition, the weight average molecular weight (M8) was determined by gel permeation chromatography (GPC).
When measured, it was found that M8=1020.

This metal-containing polycyclic aromatic polymer (4) was dissolved in air for 10
The ash obtained was heated to 00°C, subjected to alkali melting and hydrochloric acid treatment, and dissolved in water.The metal concentration of the aqueous solution was measured using an high-frequency plasma emission spectrometer (ICP). Polycyclic aromatic polymer (4)
The silicon content therein was found to be 5.2% and the titanium content to be 0.2%.

Example 2 (First step) Precursor polymer (1) 39 was prepared in the same manner as the first step of Example 1.
I got g.

(Second step) An ethanol-xylene solution (1.5%) of 5.4 g of tetrakis acetylacetonatosilconium was added to 39 g of precursor polymer (1), and after the solvent was distilled off, polymerization was carried out at 250°C for 1 hour. 39.5 g of random copolymer (2) was obtained.

(Third step) The mesophasing conditions were 420°C for 14 hours, and the hydrogenation was carried out at 95°C using metallic lithium and ethylenediamine.
A polycyclic aromatic polymer (3) was obtained in the same manner as in Example 1, except that hydrogenation was carried out for 2 hours. This polycyclic aromatic polymer (3) had a melting point of 225°C, a softening point of 231°C, and was confirmed to be potentially anisotropic pitch in the same manner as in Example 1.

(4th step) 20 g of the random copolymer (2) obtained in the 2nd step and 50 g of the polycyclic aromatic polymer (3) obtained in the 3rd step were combined into 35 g
Melt mixing was performed at 0°C for 1 hour to obtain 67 g of a polycyclic aromatic polymer containing silicon and zirconium.

This metal-containing polycyclic aromatic polymer (4) has a melting point of 242
It had a softening point of 268°C, contained 55% xylene insoluble matter, and had an average weight molecular weight of 960.

Further, the silicon and zirconium contents in this polymer were 4.1% and 0.8%, respectively.

Example 3 (1st step) 60 g of pitch obtained in Example 1 and organosilicon polymer 4
From 0 g, 57 g of precursor copolymer (1) was obtained in the same manner as in Example 1.

(Second step) An ethanol-xylene solution of 7.2 g of hafnium chloride was added to 40 g of precursor copolymer (1), and after distilling off the xylene, polymerization was carried out at 250°C for 1 hour to give 43.5 g of random copolymerization. Coalescence (2) was obtained.

(Third step) The polycyclic aromatic compound was produced in the same manner as in Example 1, except that the mesophasing conditions were 430°C for 11 hours, and the hydrogenation was carried out without a catalyst at 420°C for 1 hour at a hydrogen pressure of 80 kg/cm. A polycyclic aromatic polymer (3) was obtained. This polycyclic aromatic polymer (3) had a melting point of 233"C and a softening point of 241"C.
Similarly, it was confirmed that there was a potential anisotropic pinch.

(4th step) 20 g of the random copolymer (2) obtained in the 2nd step and 50 g of the polycyclic aromatic polymer (3) obtained in the 3rd step were combined into 3
The mixture was melt-mixed at 50°C for 1 hour to obtain 95g of a polycyclic aromatic polymer containing silicon and nophnium.

This metal-containing polycyclic aromatic polymer (4) has a melting point of 248
It had a softening point of 271°C, contained 63% xylene insoluble matter, and had an average weight molecular weight of 890.

Further, the silicon and hafnium contents in this polymer were 3.6% and 1.9%, respectively.

Comparative Example 1 (Step 1, Step 2) 200 g of the FCC slurry oil obtained in Reference Example 2 was heated to 420°C under a stream of nitrogen gas, and the light fraction at the same temperature was distilled off to obtain 114 g of light bone-removed pitch. Ta. The obtained pitch was dissolved in 500 g of xylene at 130°C to remove 69 g of the xylene insoluble portion, and then 45 g of the organosilicon polymer obtained in Reference Example 1 was added to 45 g of the xylene soluble portion of the obtained pitch. In addition, copolymerization was carried out at 400 °C for 6 hours32
g of a precursor polymer was obtained.

(Second step) 200g of the xylene soluble pitch component obtained in the first step,
Heat treatment was performed at 400° C. for 2 hours under a nitrogen gas stream to obtain 65 g of optically isotropic pitch containing no quinoline solvate. Even when shearing was applied by the method of Example 1, this pitch did not become stable (distributed) and did not contain any potential anisotropic components.

(Third step) 30 g of the precursor polymer obtained in the first step and 60 g of the heat-treated pitch obtained in the second step were heated and mixed at 340° C. for 1 hour. The weight average molecular weight (Ml, l) of the obtained product was 1450
The silicon content was 9.8% and the melting point was 185°C.

Comparative Example 2 50 g of the organosilicon polymer obtained in Reference Example 1 was added to 100 g of the light bone-removed pitch obtained in Example 1 and reacted at 400° C. for 6 hours to obtain 79 g of a precursor polymer.

The resulting polymer has a melting point of 252°C and a silicon content of 15
%, and the average weight molecular weight (M) was 1400, containing no xylene-insoluble matter and no mesophase portion.

Example 4 The metal-containing polycyclic aromatic polymer (4) obtained in Example 1, Example 2, and Example 3 was used as a spinning dope, and the diameter was 0° and 15 mm.
Melt spinning was performed using a nozzle. The obtained precursor yarn was unmelted at 300°C under air flow and fired at 1300°C under argon flow to obtain carbonaceous inorganic fibers. The yarn diameter, tensile strength, and tensile modulus of this fiber are 9.0 μ and 360 kg/mm, respectively, in the case of the dope of Example 1.
, 30 t/Sono 2, in the case of the dope of Example 2, 1
0.9μ, 365kg/ffl+12.33t/111
ffI2, in the case of doping of Example 3, 11.2μ, 3
The weight was 51 kg/II fln", 32 t 7 mm".

Observation of the cross section of the fibers using a scanning electron microscope revealed that all the fibers had a coral-like random structure, a radial-based random-radial structure, and a spiral onion structure, and the mesophase components in the dope were found to be different from spinning and non-spinning. This indicates that the fibers were oriented in the axial direction during the melting and firing process.

Comparative Example 3 The polymers obtained in Comparative Examples 1 and 2 were spun, infusible, and fired under the same conditions as in Example 4 to obtain fired yarn. The thread diameter, tensile strength, and tensile modulus of each fiber are those of Comparative Example 1.
17μ, 95 kg/mm”, 6
．． Ot 7mm'', in the case of the dope of Comparative Example 2, 1
It was 6μ, 75kg/body”, 5.Ot/decoration 2.

Further, the fiber cross section did not include any oriented structure.

Claims (2)

[Claims] (1) (A) Mainly composed of a bonding unit (Si-CH_2), or a bonding unit (Si-CH_2) and a bonding unit (Si-Si), with hydrogen atoms, lower alkyl groups, phenyl groups and It has a substituent selected from the group consisting of silyl groups, and at least one type of atom selected from the group consisting of titanium, zirconium, and hafnium is bonded to at least a portion of the silicon atoms directly or via an oxygen atom. transition metal-containing organosilicon polymer units, and (
B) an optically isotropic polycyclic aromatic compound unit containing a potential anisotropy-forming component, in which at least a portion of the silicon atoms of (A) are
A metal-containing polycyclic aromatic polymer, which is bonded to the carbon atom of the aromatic ring of (B). (2) 1) Mainly composed of a bonding unit (Si-CH_2), or a bonding unit (Si-CH_2) and a bonding unit (Si-Si), and the side chain of the silicon atom is a hydrogen atom, a lower alkyl group, a phenyl group, or At least one type of atom selected from the group consisting of titanium, zirconium, and hafnium is attached directly or via an oxygen atom to at least a portion of the silicon atoms in the main skeleton that has a silyl group and consists of the above-mentioned bonding units. At least a part of the silicon atoms of the transition metal-containing organosilicon polymer bonded to the silicon-carbon linkage with the carbon of the aromatic ring of the polycyclic aromatic compound which is petroleum-based or coal-based pitch or its heat-treated product. a random copolymer bonded through a group, and 2) a potential anisotropy-forming component obtained by hydrogenating a pitch containing a mesophase obtained by heat-treating petroleum-based or coal-based pitch and then heat-treating it again. A method for producing a metal-containing polycyclic aromatic polymer, which comprises heating-reacting and/or heating-melting an optically isotropic polycyclic aromatic compound containing the following at a temperature in the range of 200 to 500°C. .