JPH0768352B2 - Metal-containing polycyclic aromatic polymer and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an inorganic fiber excellent in mechanical properties, oxidation resistance and compatibility with a matrix for composite materials, mechanical properties,
The present invention relates to a precursor polymer suitable for producing a matrix for a composite material excellent in oxidation resistance, abrasion resistance, heat resistance and the like, a precursor polymer suitable for production, and a production method thereof.

(Prior art and its problems) Since carbon fiber is lightweight, yet has high strength and high elasticity,
It is used in a wide range of fields such as sports / leisure goods, aircraft, bicycles, and building materials.

Polyacrylonitrile was used as the raw material for the carbon fiber.
So-called pitch-based carbon fibers made from PAN-based carbon fibers and petroleum-based or coal-based pitches are known.

Pitch-based carbon fibers are generally inferior in strength to PAN-based carbon fibers, but since the raw material is inexpensive, various studies have been made on a method for increasing the strength, for example, JP-A-59-2233.
Japanese Patent Publication No. 16 discloses a method of effectively generating mesophases and orienting them during spinning.

However, since carbon fibers are basically crystalline fibers, they have the drawbacks that they are hard and easily fluffy, and that they are inferior in wettability with the matrix when they are used as a composite material.

Therefore, various surface treatment methods for carbon fibers have been proposed, and currently known methods include polyvinyl alcohol, unsaturated polyester resin, and epoxy resin for the purpose of imparting flexibility to the fiber and suppressing fuzz formation. There is a method of applying a different sizing agent to the surface, a method of oxidizing the surface by a dry method or a wet method for the purpose of improving the adhesiveness with the matrix.

Among these treatments, in particular, the method of providing the surface oxidation layer tends to deteriorate the physical properties because the fibers are damaged during the oxidation. Furthermore, carbon fibers cannot be used because they burn in an oxidizing atmosphere exceeding 500 ° C.

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

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

On the other hand, carbon fiber was used as the reinforcing fiber and carbon was used as the inorganic matrix. So-called C / C composites and carbon moldings are excellent in specific strength, specific elasticity, heat resistance in a non-oxidizing atmosphere, toughness, and friction characteristics, and are promising as heat resistant structural materials and brake materials.

However, since the matrix of C / C composites and carbon moldings consists only of carbon, it is difficult to use them for a long time in an oxidizing atmosphere. Wearability is not always sufficient, and further improvement in mechanical properties is expected.

As a method for solving the problems in the fiber, for example, JP-A-62-209139, JP-A-62-215016, mixing organic solvent-soluble components in coal-based or petroleum-based pitch and polysilane. -A method for producing an inorganic fiber having an intermediate property between silicon carbide fiber and carbon fiber by heating, synthesizing organopolyarylsilane and spinning, infusibilizing, and firing it is described.

However, in the above method, a pitch containing no organic solvent insoluble matter is selected as one of the starting materials, and the reaction is carried out under the condition that the insoluble matter is not produced even in the production of organopolyarylsilane.

That is, the spinning raw material that is the obtained product does not contain an orientation component that is essential for developing the strength of the carbon fiber, and no highly elastic inorganic fiber is obtained from the spinning raw material.

Further, in the method of the above publication, although the heat resistance in the inert gas is improved as the pitch component is increased, the oxidation resistance is deteriorated and the mechanical properties are remarkably deteriorated.

In addition, as a method for compensating for the essential drawbacks of the carbon matrix, in Walker (JW), Am. Ceram. Soc. Bull. 62 (1983) 916, C / C composite was impregnated with an organosilicon polymer. After that, a method of thermally decomposing and introducing a silicon carbide component into the matrix is described, but the bending strength of the obtained composite material is as low as 158 MP.

Also, Proc.of Int.Symp.on Ceramic, Compon.for Engin
e, 1983, Japan, p505, Fittour (E.Fitze
r) et al. describe a method of impregnating a C / C composite with a silicon melt to convert the matrix into silicon carbide, but the obtained composite material remains unreacted between the matrix particles. Because of the metallic silicon, which undergoes creep metamorphism at high temperatures above 1300 ° C, it does not have the high-temperature characteristics of C / C composites.

In any of the above processes, in addition to the conventional complicated C / C composite manufacturing process, a more complicated process was added, which made industrial use difficult.

Therefore, there is a strong demand for the development of a precursor polymer that can be easily converted into an excellent carbonaceous inorganic fiber or a matrix for a composite material by mineralization.

(Means for Solving Problems) An object of the present invention is to provide an inorganic fiber having excellent mechanical properties, oxidation resistance, and compatibility with a matrix for a composite material, mechanical properties, oxidation resistance, and abrasion resistance. Another object of the present invention is to provide a precursor polymer which is suitable for producing a matrix for a composite material excellent in heat resistance and the like, a molded article, and the like, and which solves the above problems, and a method for producing the precursor polymer.

According to the present invention, (A) binding unit (Si-CH _2), or binding units (Si-CH ₂₎
With a substituent selected from the group consisting of a hydrogen atom, a lower alkyl group, a phenyl group and a silyl group in the side chain of the silicon atom, and a bond unit (Si-Si).
The ratio of the total number of --CH ₂ ) to the total number of bonding units (Si--Si) is from 1: 0 to
A transition metal-containing organosilicon compound in which at least one atom selected from the group consisting of titanium, zirconium and hafnium in the range of 20 is bonded to at least a part of silicon atoms directly or through an oxygen atom. Coalescing unit,
And (B) a polycyclic aromatic compound unit that is optically isotropic at room temperature but is in a state (hereinafter referred to as a pre-mesophase state) that can be converted to a mesophase state by heating at 600 ° C. or higher. And at least a part of the silicon atom of (A) above is
A random copolymer is formed by bonding carbon atoms of the aromatic ring of (B) through a silicon-carbon linking group, and the weight ratio of (A) to (B) is 1: 0.5 to 200. The content of silicon atoms is 0.25 to 30% by weight, the content of at least one atom selected from the group consisting of titanium, zirconium and hafnium is 0.005 to 10% by weight, and the weight average molecular weight is 200 to 11000. A metal-containing polycyclic aromatic polymer is provided.

Further, according to the present invention, i) a bond unit (Si—CH ₂ ), or a bond unit (Si—CH ₂ ) and a bond unit (Si—Si) is mainly contained, and a hydrogen atom, a Alkyl group, having a phenyl group or a silyl group, to the silicon atom of the main skeleton consisting of the above-mentioned bonding unit, at least one atom selected from the group consisting of titanium, zirconium and hafnium, directly or through an oxygen atom, At least a part of the silicon atoms of the transition metal-containing organosilicon polymer bonded to at least a part of the silicon atoms is a petroleum-based or coal-based pitch or a heat-treated product of the aromatic ring of the polycyclic aromatic compound. 100 parts by weight of a random copolymer bonded to carbon through a silicon-carbon linking group, and ii) a pre-mesophase mainly obtained by hydrotreating petroleum-based or coal-based pitch under a reduced pressure. Provided is a method for producing a metal-containing polycyclic aromatic polymer, which comprises reacting 5 to 900 parts by weight of a polycyclic aromatic compound in a state of heating and / or heating and melting at a temperature in the range of 200 to 500 ° C. To be done.

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

The metal-containing polycyclic aromatic polymer (4) of the present invention comprises the constituent components (A) and (B), wherein at least a part of the silicon atoms of the constituent component (A) is an aromatic component of the constituent component (B). It is bonded to a ring carbon atom. Component (A) and component (B)
The weight ratio of is 0.5 to 200.

When the weight ratio of the constituent component (A) to the constituent component (B) is less than 0.5, the premesophase component in the metal-containing polycyclic aromatic polymer (4) is insufficient, and, for example, an inorganic fiber is produced from this polymer. However, only those with low strength and elastic modulus can be obtained. On the other hand, when the ratio exceeds 200, the oxidation resistance of the inorganic compound of the polymer is deteriorated due to the shortage of the organosilicon component in the metal-containing polycyclic aromatic polymer (4), and the metal-containing polycyclic aromatic polymer (4) may be deteriorated. The wettability becomes low.

The metal-containing polycyclic aromatic polymer (4) of the present invention contains 0.25 to 30% of silicon atoms and has a weight average molecular weight of 200 to 1
At 1000, the melting point is 180-350 ° C.

When the content of silicon atoms in the metal-containing polycyclic aromatic polymer (4) is less than 0.25%, Si in the inorganic compound of the polymer,
Since the amount of the amorphous phase composed of C and O or the β-SiC ultrafine particles is too small, for example, the wettability to the FRP matrix and the oxidation resistance are not remarkably improved. It is not possible to improve the heat resistance in a highly elastic, non-oxidizing atmosphere due to the orientation of ultrafine graphite particles in the oxide.

The weight average molecular weight of the metal-containing polycyclic aromatic polymer (4) is
Those below 200 cannot provide high-performance inorganic fibers, composites, and molded products because they contain almost no pre-mesophase, and above 11000, they have a high melting point and have poor fluidity and can be molded into any shape. It gets harder.

When the melting point of the metal-containing polycyclic aromatic polymer (4) is lower than 180 ° C., it does not substantially contain a premesophase, and when this polymer is spun to produce an inorganic fiber,
The precursor yarn is easily fused when infusibilized, and a fired yarn having high strength and elastic modulus cannot be obtained. On the other hand, when the melting point of the polymer is higher than 350 ° C., the softening / flowing temperature becomes high and the polymer is decomposed, which is not preferable.

The metal-containing polycyclic aromatic polymer (4) contains 0.005 to 10% of M (M is at least one element selected from Ti, Zr and Hf) in addition to the silicon atom. Since the polymer mineralization contains M, it has better mechanical properties and compatibility with other matrices.

When the content of M is less than 0.005%, the above properties are hardly exhibited, and when it exceeds 10%, a high melting point product having extremely advanced crosslinking and unreacted MX ₄ are mixed in the polymer. Therefore, melt spinning using the polymer as a dope becomes extremely difficult, and foaming during heating adversely affects molding.

The metal-containing polycyclic aromatic polymer (4) preferably contains 10 to 90% of an insoluble matter in an organic solvent such as benzene, toluene, xylene and tetrahydrofuran.

When the content of the metal-containing polycyclic aromatic polymer (4) insoluble in the organic solvent is less than 10%, the orientation of the carbon microcrystals in the fiber axis direction hardly occurs even if the polymer is melt-molded and mineralized. Inorganic fibers, molded products, composite materials, etc. having excellent mechanical properties cannot be obtained. When the content of the insoluble matter in the organic solvent is more than 90%, the polymer has a high melting point and a high softening point, which makes spinning and molding of the polymer difficult.

Since the metal-containing polycyclic aromatic polymer (4) of the present invention softens and flows at a relatively low temperature, it is preferably used as a precursor of inorganic fibers, for example.

Next, a method for producing the metal-containing polycyclic aromatic polymer (4) of the present invention will be described.

First, an organosilicon polymer and pitch are heated and reacted in an inert gas, preferably at a temperature in the range of 250 to 500 ° C, to prepare a precursor polymer (1).

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 is obtained by

The organosilicon polymer, binding unit (Si-CH _2), or binding units (Si-CH ₂₎ primarily consists binding units (Si-Si), the total number pairing unit of coupling units (Si-CH ₂₎ (Si-S
The ratio of the total number of i) is in the range of 1: 0 to 20.

The weight average molecular weight (M _w ) of the organosilicon polymer is generally
Those having a molecular weight of 300 to 1,000 and a _Mw of 400 to 800 are particularly preferable for preparing a random copolymer (2) which is an intermediate raw material for obtaining excellent inorganic fibers, composite materials, molded articles and the like.

Another starting material, pitch, is a pitch obtained from petroleum and / or coal, and in particular, a heavy oil obtained by fluid catalytic cracking of petroleum, a distillate component obtained by distilling the heavy oil, or It is the residual oil and the pitch obtained by heat treating them.

There are no particular restrictions on the properties and physical properties of the raw oil and / or the source of raw coal and the pitch obtained, but the metal-containing polycyclic aromatic polymer (4) as the final product is used as a raw material dope for the production of inorganic fibers. When used, it contains 5 to 98% by weight of a component insoluble in an organic solvent such as benzene, toluene, xylene, and tetrahydrofuran, has a weight average molecular weight ( _Mw ) of 300 to 3000, and a melting point of 70 to 200 ° C. Is preferred.

The weight average molecular weight is a value determined as follows. That is, if the pitch does not contain the organic solvent insoluble matter for gel permeation chromatograph (GPC) measurement such as benzene, toluene, xylene, tetrahydrofuran, chloroform and dichlorobenzene, the GPC measurement is performed as it is,
When the pitch contains the organic solvent insoluble matter, it is subjected to hydrogenation under mild conditions, and the GPC measurement is performed after changing the organic solvent insoluble matter to the organic solvent soluble ingredient (containing the organic solvent insoluble matter. The weight average molecular weight of the polymer is a value obtained by performing the same treatment as above).

The ratio of the pitch used is 2 to 1 per 100 parts of the organosilicon polymer.
It is preferably 900 parts. When the proportion of the pitch component used is too small, the amount of the organic silicon component increases, and the polycyclic aromatic compound is mainly in the premesophase state (hereinafter, simply referred to as "polycyclic aromatic compound (3)"). The compatibility with and deteriorates, the homogeneity at the time of melting is impaired, and when a fiber or a molded body is manufactured, the elastic modulus decreases. On the other hand, if the proportion is too large, the amount of the organosilicon polymer component is too small, and the wettability to the matrix and the oxidation resistance of the composite material produced from the polymer of the present invention deteriorate.

When the reaction temperature of the above reaction is excessively low, the bond between the silicon atom and the aromatic carbon is hard to be generated, and when the reaction temperature is excessively high, decomposition and high molecular weight of the generated precursor polymer (1) occur violently. Not preferable. The precursor polymer (1) referred to here includes, in addition to the copolymer in which the organosilicon polymer and the pitch are bonded via the silicon-carbon linking group, the polycondensate of each of the organosilicon polymer and the pitch. .

Next, the precursor copolymer (1) and the transition metal compound represented by the formula MX ₄ are reacted in a temperature range of 100 to 500 ° C. to prepare a random copolymer (2).

In the above MX ₄ , X may be any as long as M can be bonded to silicon of the precursor polymer (1) by condensation or directly or through an oxygen atom, and there is no particular limitation, but a halogen atom, an alkoxy group or β -Complexing groups such as diketones are preferred.

If the reaction temperature is excessively low, the condensation reaction between the precursor polymer (1) and the formula MX ₄ will not proceed, and if the reaction temperature is excessively high, the crosslinking reaction of the precursor polymer (1) via M will be excessive. Gelation occurs, the precursor polymer (1) itself condenses to a high molecular weight, or in some cases MX ₄ is volatilized to obtain excellent inorganic fibers, composite materials, and molded products. A random copolymer (2) as an intermediate raw material cannot be obtained. As an example, when M is Ti and X is OC ₄ H ₉ , the reaction temperature is 200.
~ 400 ° C is suitable.

By this reaction, a random copolymer (2) in which at least a part of silicon atoms of the precursor polymer (1) is bonded to the metal M directly or via an oxygen atom is prepared. Metal M
The -MX ₃ or -O-M to a silicon atom of the precursor polymer (1)
It may be bonded in a side chain form by a bond mode such as X ₃ , or may be a bond mode in which the silicon atom of the precursor polymer (1) is crosslinked directly or via oxygen.

As the method for preparing the random copolymer (2), in addition to the method described above, a method of reacting an organosilicon polymer with MX ₄ and further reacting the obtained product with pitch can be used. .

Nitrogen, argon and the like are preferably used as the inert gas.

The polycyclic aromatic compound (3) can be obtained by, for example, treating a petroleum-based or coal-based pitch with tetrahydroquinoline, or by adding a catalyst if necessary and then hydrogenating under a hydrogen pressure to form a condensed aromatic ring in the pitch. 1st part hydrogenation
The hydrogenation pitch obtained in the stage treatment and the first stage treatment is
It can be prepared by a second stage treatment of heating at high temperature under reduced pressure for a short time.

In the first-stage treatment, for example, when hydrogenation is carried out using tetrahydroquinoline, hydrogenation can be carried out by adding 30 parts or more of tetrahydroquinoline to 100 parts by weight of pitch and heating to 300 ° C to 500 ° C. . When hydrogenated with hydrogen, a solvent such as quinoline, a cobalt-molybdenum-based catalyst, an iron oxide-based catalyst or the like is added to the raw material pitch as needed, and the hydrogen partial pressure is 10 kg / cm ² or more under a pressure of 400 ° C. ~Five
Hydrogenation can be carried out at 00 ° C. The product thus obtained is, if necessary, subjected to filtration, removal of the solvent and light components, and a second stage treatment.

The second stage treatment is a high temperature heat treatment under reduced pressure, preferably a pressure of 50 mmHg or less, a temperature of 440 ° C. or more and a heat treatment of 60 minutes or less. The processing time is determined by the processing temperature,
It is preferable that the treatment is carried out at a temperature as high as possible for a short time, and in particular, treatment within 15 minutes is a polycyclic aromatic compound for obtaining a metal-containing polycyclic aromatic polymer (4) having excellent spinnability. Suitable for producing compound (3).

The pre-mesophase state here is a state that is optically isotropic at room temperature, but can be converted to a mesophase state by heating at a high temperature (600 ° C. or higher).

In other words, if the polycyclic aromatic compound in this state is spun alone, infusibilized, and fired, the mesophase polycyclic ring is formed because the orientation occurs in the firing process even though spinning is possible at a relatively low temperature. Similar to using an aromatic compound,
A highly elastic carbon fiber can be obtained.

Further, even if the polycyclic aromatic compound in the pre-mesophase state contains a small amount of the mesophase and / or isotropic polycyclic aromatic compound, the final product is a silicon-containing polycyclic aromatic polymer. It does not affect the nature of.

Polycyclic aromatic compound (3) obtained by the above production method
Generally has a melting point of 200 to 350 ° C and a weight average molecular weight of 200.
~ 6000 and the quinoline insoluble content is 5% or less.

Random copolymer (2) and polycyclic aromatic compound (3)
A metal-containing polycyclic aromatic polymer (4) is obtained by heating and / or melting at 200 to 500 ° C.

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 less than 5 parts, the polycyclic aromatic compound (3) will be insufficient. , Even if the obtained polymer is made inorganic, high elastic fibers and molded products cannot be obtained.If it is more than 900 parts, fibers and acid-resistant which have excellent wettability to the matrix due to lack of silicon component A molded product with improved chemical conversion cannot be obtained.

When the melt-mixing temperature is lower than 200 ° C, an infusible portion is generated,
If the system becomes heterogeneous, and if the melt-mixing temperature is higher than 500 ° C, the condensation reaction will proceed violently, and the resulting polymer will have a high melting point and lose its fluidity.

(Effect) Since the metal-containing polycyclic aromatic polymer (4) according to the present invention contains a transition metal-containing organosilicon copolymer and a polycyclic aromatic compound in a pre-mesophase state in the polymer,
By melt spinning, infusibilizing, and firing this polymer,
Amorphous and / or β-SiC, MC, a solid solution of β-SiC and MC, and MC _1-X (0 <X <1) on Si ultrafine graphite crystals High strength and high elasticity of structure in which aggregates of ultrafine crystalline particles and amorphous SiO _y (0 <y ≦ 2) and MO _z (0 <z ≦ 2) are dispersed, and wettability with plastic An excellent carbon-based inorganic fiber can be obtained. As described above, there has been no fiber that can satisfy both mechanical properties and wettability with plastics at the same time, so that development of applications for FRP is particularly expected.

Further, the fiber obtained from the polymer of the present invention enables the use of the carbon-based fiber in a high temperature oxidizing atmosphere, and at the same time, by subjecting the polymer of the present invention to a molding process, an oxidation-resistant carbon-based material and a fiber-reinforced ceramic. It can be used as a (FRC) matrix. Further, the present invention has a great advantage in terms of effective use of pitch.

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

Reference Example 1 (Manufacturing Method of Organosilicon Polymer) 2.5 xylene and 400 g of anhydrous sodium were placed in a three-necked flask of 5, heated to the boiling point of xylene under a nitrogen gas stream, and dimethyldichlorosilane 1 was added dropwise for 1 hour. After completion of the dropping, the mixture was heated under reflux for 10 hours to form a precipitate. The precipitate was filtered, washed with methanol and then with water to obtain 420 g of white powdery polydimethylsilane.

400 g of this polydimethylsilane, a gas introduction tube, a stirrer,
A three-necked flask equipped with a condenser and a distilling tube was charged into a three-necked flask, and heat-treated at 420 ° C under a nitrogen stream of 50 ml / min with stirring, and 350 g of a colorless transparent slightly viscous liquid was put in a distilling receiver. Got

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

The infrared absorption spectrum of this substance was measured and found to be 65
Absorption of Si-CH ₃ at 0-900 cm ^-1 and 1250 cm ^-1 , Si at 2100 cm ^-1
Absorption of -H, Si-CH ₂ -Si absorption of the of 1020 cm ^-1 and near 1355 cm ^-1, absorption of CH was observed at 2900 cm ^-1 and 2950 cm ^-1,
Further, when the far-infrared absorption spectrum of this substance was measured, absorption of Si-Si was observed at 380 cm ^-1 , and thus the obtained liquid substance was mainly composed of (Si-CH ₂ ) bond units and (Si-Si). It was found to be an organosilicon polymer having a bonding unit and having a hydrogen atom and a methyl group in the side chain of silicon.

From the results of nuclear magnetic resonance analysis and infrared absorption analysis, this organosilicon polymer shows that the total number of (Si—CH ₂ ) bond units is
It was confirmed that the polymer had a ratio of the total number of -Si) bond units of approximately 1: 3.

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

Measurement of the infrared absorption spectrum of this material, the absorption peak similar to that described above was observed, the material consists predominantly (Si-CH ₂₎ coupling units and (Si-Si) bond unit, hydrogen on the side chain of the silicon It was found to be an organosilicon polymer having atoms and methyl groups.

From the results of nuclear magnetic resonance analysis and infrared absorption analysis, this organosilicon polymer shows that the total number of (Si—CH ₂ ) bond units is
It was confirmed that the polymer had a ratio of the total number of -Si) bond units of about 7: 1.

Reference Example 2 (Production method of FCC slurry oil) Among petroleum fractions, high-boiling substances above light oil were subjected to fluid catalytic cracking at a temperature of 500 ° C in the presence of a silica-alumina cracking catalyst.
Fractionation was performed to obtain a residue from the bottom of the column. Below this residue
Called FCC slurry oil.

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

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 stream, the distillate at the same temperature was distilled off, and the residue was hot filtered at 200 ° C. The infusible part at the same temperature was removed to obtain 225 g of a light material removal pitch.

The light content removal pitch was an optically isotropic pitch containing 75% xylene insoluble matter.

21 g of the organosilicon polymer obtained in Reference Example 1 and 20 ml of xylene were added to 49 g of this pitch, the temperature was raised with stirring, and xylene was distilled off and reacted at 400 ° C. for 6 hours to obtain 39 g of the precursor polymer (1). It was

As a result of infrared absorption spectrum measurement, this precursor polymer (1) was found to have Si-H bonds (IR: 2100c) present in the organosilicon polymer.
m- ¹ ) and a new Si-C (carbon of benzene ring) bond (IR: 1135 cm ^-1 ) were observed, which indicates that some of the silicon atoms in the organosilicon polymer are polycyclic aromatic rings. It was found to be a polymer having directly bonded moieties.

(Second step) 39 g of the precursor polymer (1) was added to tetraoctoxytitanium [Ti (O
C ₈ H ₁₇ ) ₄ ] 2.75 g of xylene solution (25% xylene solution 11
g) was added, xylene was distilled off, and the mixture was reacted at 340 ° C. for 2 hours,
40 g of random copolymer (2) was obtained.

This polymer does not contain a xylene-insoluble part and has a weight average molecular weight of
The melting point was 1650 and the melting point was 272 ° C.

(Third step) 400 g of FCC slurry oil obtained in Reference Example 2 and 1,2,3,4-
450 g of tetrahydroquinoline and 300 g in an autoclave
After hydrogenation at 10 ° C for 10 minutes, tetrahydroquinoline was distilled off to obtain hydrogenated pitch.

This pitch was charged in a metal container, immersed in a tin bath under a reduced pressure of 10 mmHg, and heat-treated at 450 ° C. for 10 minutes to obtain 62 g of a polycyclic aromatic compound (3).

The obtained polycyclic aromatic compound (3) has a melting point of 230 ° C.,
It had a softening point of 238 ° C. and contained 2% of quinoline insoluble matter.

(Fourth step) 40 g of the random copolymer (2) obtained in the second step and the third step
80 g of the polycyclic aromatic compound (3) obtained in the step was melt-mixed in a nitrogen atmosphere at 350 ° C. for 1 hour to obtain a metal-containing polycyclic aromatic polymer (4) in a uniform state.

The metal-containing polycyclic aromatic polymer (4) was optically isotropic, but contained 50% xylene-insoluble matter and had a melting point of 25.
At 4 ℃, the softening point is 271 ℃, hydrogenated under mild conditions,
When the weight average molecular weight (M _w ) was measured by gel permeation chromatography (GPC), M _w = 1100
Met.

This metal-containing polycyclic aromatic polymer (4) was treated with 1000
After heating to ℃, the resulting ash is alkali-melted and treated with hydrochloric acid, dissolved in water, and the aqueous solution is subjected to metal concentration measurement using a high-frequency plasma emission spectrophotometer (ICP). It was found that the silicon content in the aromatic polymer (4) was 5.8% and the titanium content was 0.2%.

Example 2 (1st process) It carried out similarly to the 1st process of Example 1, and obtained the precursor polymer (1).

(Second Step) 39 g of the precursor polymer (1) was dissolved in 5.4 g of tetrakisacetylacetonato zirconium in ethanol-xylene solution (1.5 g).
%) Was added, the solvent was distilled off, and the mixture was polymerized at 250 ° C. for 1 hour to obtain 39.5 g of a random copolymer (2).

(Third Step) The FCC oil obtained in Reference Example 2 was hydrogenated in an autoclave at 350 ° C. for 1 hour at a hydrogen pressure of 80 kg / cm ² using a nickel-cobalt solid catalyst containing zeolite as a simple substance. After removing a fraction of 320 ° C or less from the obtained oil under reduced pressure of 15 mmHg, the obtained pitch was heated under reduced pressure of 2 mmHg for 10 minutes at 440 ° C, melting point 248 ° C, softening point 255 ° C, quinoline. A polycyclic aromatic compound (3) having an insoluble content of 1% was obtained.

(Fourth step) 20 g of the random copolymer (2) obtained in the second step and 50 g of the polycyclic aromatic compound (3) obtained in the third step are melt-mixed at 350 ° C. for 1 hour to give 67 g of silicon and zirconium. A polycyclic aromatic polymer containing was obtained.

This metal-containing polycyclic aromatic polymer (4) has a melting point of 254.
℃, softening point 273 ℃, containing 61% xylene insoluble,
The weight average molecular weight (M _w ) was 1010.

The contents of silicon and zirconium in this polymer were 4.0% and 0.8%, respectively.

Example 3 (First Step) From the pitch 60 g and the organosilicon polymer 40 g obtained in Example 1, 57 g of the precursor copolymer (1) was obtained in the same manner as in Example 1.

(Second step) To 40 g of the precursor copolymer (1), 7.2 g of an ethanol-xylene solution of hafnium chloride was added, and xylene was distilled off.
Polymerization was performed at 0 ° C. for 1 hour to obtain 43.5 g of random copolymer (2).

(Third Step) The FCC oil obtained in Reference Example 2 was autoclaved at 430 ° C. in a nitrogen atmosphere at an autogenous pressure of 95 kg / cm ² (hydrogen partial pressure was 21 kg /
It was cm ² . ) Condition for 1 hour, then remove the fraction below 320 ℃ under reduced pressure of 10mmHg, the resulting pitch is 10mmHg
The mixture was heated at 450 ° C. for 3 minutes under reduced pressure of g to obtain a polycyclic aromatic compound (3) having a melting point of 251 ° C., a softening point of 260 ° C. and a quinoline insoluble content of 5%.

(Fourth step) 20 g of the random copolymer (2) obtained in the second step and 80 g of the polycyclic aromatic compound (3) obtained in the third step were melt mixed at 350 ° C. for 1 hour, and 96 g of silicon and hafnium A polycyclic aromatic polymer containing was obtained.

This metal-containing polycyclic aromatic polymer (4) has a melting point of 253 ° C.
It contained 71% xylene-insoluble matter and had an average weight molecular weight of 870.

The contents of silicon and hafnium in this polymer were 3.6% and 1.9%, respectively.

Comparative Example 1 (First Step) 200 g of the FCC slurry oil obtained in Reference Example 2 was heated to 420 ° C. under a nitrogen gas stream, and the light fraction at the same temperature was distilled off to obtain 114 g of a light fraction removal pitch. The obtained pitch is 130
After dissolving in 500 ml of xylene at 500 ° C and removing 69 g of xylene-insoluble matter, 45 g of xylene-soluble matter in the obtained pitch was added with 45 g of the organosilicon polymer obtained in Reference Example 1 and copolymerized at 400 ° C for 6 hours. Then, 32 g of a precursor polymer was obtained.

(Second Step) 200 g of the xylene-soluble pitch component obtained in the first step was heat-treated under a nitrogen gas stream at 400 ° C. for 2 hours to obtain 65 g of an optically isotropic pitch containing no quinoline-insoluble matter. .

(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 obtained product had a weight average molecular weight (M _w ) of 1450 and a silicon content of 9.8.
%, But the melting point was 185 ° C.

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

The obtained polymer has a melting point of 252 ° C., a silicon content of 15%,
The average weight molecular weight (M _w ) was 1400.

Example 4 The metal-containing polycyclic aromatic polymer (4) obtained in Examples 1, 2 and 3 was used as a spinning dope and melt-spun using a nozzle having a diameter of 0.15 mm. The obtained precursor yarn was infusible at 300 ° C. under air flow, and fired at 1300 ° C. under an argon stream to obtain a carbonaceous inorganic fiber. The thread diameter, tensile strength, and tensile elastic modulus of this fiber are 9.5 μ, 345 kg / mm ² , and 32 t / mm ² in the case of the dope of Example 1 and 12.0 μ in the case of the dope of Example 2, respectively. It was 350 kg / mm ² , 34 t / mm ² , and in the case of the dope of Example 3, it was 12.5 μ, 330 kg / mm ² , 33 t / mm ² .

As a result of observing the fiber cross section with a scanning electron microscope, all the fibers have a coral-like random structure, a radial-based random-radial structure, and a spiral onion structure. It was shown that the fibers were oriented in the fiber axis direction during the melting and firing processes.

Comparative Example 3 The polymers obtained in Comparative Examples 1 and 2 were spun, infusibilized and fired under the same conditions as in Example 4 to obtain a fired yarn. The yarn diameter, tensile strength, and tensile elastic modulus of each fiber are shown in Comparative Example 1 respectively.
In the case of the dope of No. 7, 17 μ, 95 kg / mm ² , 6.0 t / mm ² , and in the case of the dope of Comparative Example 2, 16 μ, 75 kg / mm ² , 5.0 t / mm ² .

Further, the fiber cross section did not include a portion having an oriented structure.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical display location D01F 9/10 Z (72) Inventor Masaki Shibuya 5 Ube Industries, Ltd., Ube City, Yamaguchi Prefecture 5 Ube Industries Ltd. Examiner in the Ube Laboratory of the Company Yukio Hokura (56) References JP-A-63-182348 (JP, A)

Claims (2)

[Claims] 1. A bonding unit (Si—CH ₂ ), or a bonding unit (Si—CH ₂ ) and a bonding unit (Si—Si) as a main component (A) having a hydrogen atom or a lower alkyl group in the side chain of a silicon atom. , Having a substituent selected from the group consisting of a phenyl group and a silyl group, the total number of bond units (Si-CH ₂ ) vs. bond units (Si-Si)
The total number ratio of is in the range of 1: 0 to 20, and at least one atom selected from the group consisting of titanium, zirconium and hafnium is bonded to at least a part of silicon atoms directly or through an oxygen atom. A transition metal-containing organosilicon polymer unit, and (B) a polycyclic group that is mainly optically isotropic at room temperature but can be converted to a mesophase state by heating at 600 ° C. or higher. An aromatic compound unit, wherein at least a part of the silicon atom of (A) above is
A random copolymer is formed by bonding carbon atoms of the aromatic ring of (B) through a silicon-carbon linking group, and the weight ratio of (A) to (B) is 1: 0.5 to 200. The content of silicon atoms is 0.25 to 30% by weight, the content of at least one atom selected from the group consisting of titanium, zirconium and hafnium is 0.005 to 10% by weight, and the weight average molecular weight is 200 to 11000. A metal-containing polycyclic aromatic polymer characterized in that: 2. A bonding unit (Si—CH ₂ ) or a bonding unit (Si—CH ₂ ) and a bonding unit (Si—Si) as a main component, and a hydrogen atom or a lower alkyl group in the side chain of the silicon atom. , A phenyl group or a silica group, and at least one kind of atom selected from the group consisting of titanium, zirconium and hafnium is directly or through an oxygen atom added to the silicon atom of the main skeleton consisting of the above-mentioned bonding unit, a silicon atom. At least a part of the silicon atoms of the transition metal-containing organosilicon polymer bonded to at least a part of the above are carbon and silicon of the aromatic ring of the polycyclic aromatic compound which is a petroleum-based or coal-based pitch or a heat-treated product thereof. 100 parts by weight of a random copolymer bonded via a carbon linking group, and ii) a hydrolyzed petroleum-based or coal-based pitch and then heat-treated under reduced pressure, which is mainly in a pre-mesophase state. The Jo aromatic compound 5-900 parts by weight, 200 to 500 method for producing a metal-containing polycyclic aromatic polymer, which comprises heating the reaction and / or heating and melting at a temperature in the range of ° C..