JPH0725891B2 - 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 provides a carbon-based material which has excellent mechanical properties due to infusibilization and firing, and has significantly improved oxidation resistance and wettability to a matrix for composite materials. The present invention relates to a precursor polymer which becomes an inorganic fiber and a method for producing the same.

(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 with a dry method or a wet method for the purpose of improving the contact property 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.

As a method for satisfying this demand, for example, Japanese Patent Laid-Open No. 62-2091
The methods described in Japanese Patent Laid-Open No. 39 and Japanese Patent Laid-Open No. 62-215016 have been proposed.

In these publications, an organic solvent-soluble component in coal-based or petroleum-based pitch and polysilane are mixed and heated to synthesize an organopolyarylsilane, which is spun, infusibilized,
A method for producing an inorganic fiber having properties intermediate between silicon carbide fiber and carbon fiber by firing 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.

Therefore, the spinning raw material, which is the obtained product, does not contain the insoluble matter containing the mesophase, which is said to be the most important component for expressing the strength of the carbon fiber.

The inorganic fiber obtained by spinning, infusibilizing, and firing the above spinning raw material has a (002) diffraction line corresponding to graphite crystals of carbon depending on the conditions, but the orientation peculiar to the pitch fiber is not recognized and high elasticity is obtained. You can't get the rate. Further, in the method of the above-mentioned publication, as the pitch component increases, the heat resistance in the inert gas improves, but the oxidation resistance decreases conversely,
Moreover, there is a problem in that the mechanical properties are significantly reduced.

(Means for Solving Problems) An object of the present invention is to solve the above problems and to have a characteristic of high elasticity of pitch fibers, and to have excellent strength, oxidation resistance, and wettability to a composite matrix. It is to provide a precursor polymer of carbon-based inorganic fibers.

According to the present invention, (A) binding unit (Si-CH _2), or binding units (Si-C
H ₂ ) and a bonding unit (Si-Si), having a side chain group 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 bonding unit ( The ratio of the total number of Si-CH ₂ ) to the total number of bonding units (Si-Si) 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 directly bonded. Alternatively, a transition metal-containing organosilicon polymer unit bonded to at least a part of a silicon atom via an oxygen atom, and (B) a polycyclic aromatic compound unit in a mesophase state in which the skeleton component is mainly a condensed ring structure. , And (C) the skeleton component is mainly a condensed ring structure and is composed of a polycyclic aromatic compound unit having an optically isotropic phase, and at least a part of the silicon atom in (A) above is
A random copolymer is formed by binding the carbon atom of the aromatic ring of (B) and / or (C) through a silicon-carbon linking group, and forms the random copolymer of (A), (B) and The weight ratio with the total of (C) is 1: 0.5 to 5000, the above (B)
And (C) have a weight ratio of 1: 0.02 to 4, a silicon atom content of 0.01 to 30 wt%, and a content of at least one atom selected from the group consisting of titanium, zirconium, and hafnium of 0.005. A metal-containing polycyclic aromatic polymer is provided which is characterized by having a content of -10% by weight and a weight average molecular weight of 200-11,000.

Further according to the invention, 1) binding unit (Si-CH _2), or binding units (Si-CH ₂₎
And a bond unit (Si-Si), which has a hydrogen atom, a lower alkyl group, a phenyl group and a silyl group in the side chain of silicon, and a silicon atom in the main skeleton composed of the above bond unit, T
i, Zr and at least one atom selected from Hf is bonded directly or through an oxygen atom, at least a part of the silicon atoms of the transition metal-containing organic silicon polymer, a petroleum-based or coal-based pitch or its A heat-treated product, a random copolymer bonded to carbon of an aromatic ring of a polycyclic aromatic compound obtained from a pitch containing an organic solvent insoluble matter, and 2) a mesophase obtained from a petroleum-based or coal-based pitch Alternatively, a polycyclic aromatic compound consisting of both a mesophase and an optically isotropic phase (hereinafter, both are collectively referred to as a mesophase polycyclic aromatic compound) at a temperature in the range of 200 to 500 ° C. There is provided a method for producing a metal-containing polycyclic aromatic polymer, which comprises heating and / or melting with heat.

First, the metal-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 units of component content are% by weight.

The metal-containing polycyclic aromatic polymer of the present invention comprises the constituent components (A), (B) and (C), and at least a part of the silicon atoms of the constituent component (A) is the constituent component (B) and / or Alternatively, it is bonded to a carbon atom of the aromatic ring of the constituent component (C). The weight ratio of the component (A) to the sum of the component (B) and the component (C) is usually 1: 0.5 to 5000,
It is preferably 1: 0.5 to 500, and the weight ratio of the component (B) to the component (C) is 1: 0.02 to 4.

When the weight ratio of the constituent component (A) to the sum of the constituent component (B) and the constituent component (C) is less than 0.5, the mesophase component in the metal-containing polycyclic aromatic polymer is insufficient, and for example, it is more inorganic than the polymer. Even if fibers are produced, only those having a low strength and a low elastic modulus are obtained, and when the above ratio exceeds 5000, this weight is increased due to the lack of the organosilicon component in the metal-containing polycyclic aromatic polymer. The oxidation resistance of the inorganic compound is reduced,
Furthermore, the wettability with plastics becomes worse.

If the weight ratio of (C) to (B) is less than 0.02, spinning is extremely difficult when melt-spinning a metal-containing polycyclic aromatic polymer, such as a decrease in spinnability and a breakage due to uneven viscosity of the dope. If the above ratio exceeds 4, the strength of the inorganic fiber obtained from the polymer due to lack of mesophase component in the silicon-containing polycyclic aromatic polymer,
It has a low elastic modulus.

In addition, in the constituent component (A), the bonding unit (Si-
The ratio of the total number of CH ₂ ) to the total number of bonding units (Si-Si) is 1: 0 to
Within the range of 20, the binding unit (M) of the fiber metal compound is contained in an amount of 0.2% to 35% with respect to the total weight of the binding unit (Si—CH ₂ ) and the binding unit (Si—Si).

The metal-containing polycyclic aromatic polymer of the present invention generally contains 0.01 to 30%, preferably 0.05% to 30% of silicon atom, and usually 0.005 to 10% of M, and has a weight average. It has a molecular weight of 200 to 11000 and a melting point of 200 to 400 ° C. When the silicon atom content in the metal-containing polycyclic aromatic polymer is less than 0.01%, for example, the wettability of the FRP matrix to the matrix and the oxidation resistance of the fiber are not significantly improved, and when it exceeds 30%, High elasticity due to the orientation of ultrafine graphite crystals in the inorganic fiber, heat resistance improvement in a non-oxidizing atmosphere cannot be achieved.

Further, the metal-containing polycyclic aromatic polymer has M
Therefore, when an inorganic fiber is produced from the polymer, mechanical properties and wettability with respect to plastic are further improved, but when the content of M is less than 0.05%, the above properties are hardly exhibited and 10%. If it exceeds the above range, the high-melting point product having undergone extreme crosslinking and unreacted MX ₄ are mixed in the polymer, and spinning becomes difficult.

Since the metal-containing polycyclic aromatic polymer having a weight average molecular weight of less than 200 practically contains almost no mesophase, a highly elastic inorganic fiber, composite material, or molded product is obtained from such a polymer. When it is more than 11000, the melting point becomes high, and it is difficult to soften and flow, and spinning and molding become difficult.

When the melting point of the metal-containing polycyclic aromatic polymer is lower than 200 ° C., it does not substantially contain mesophase, and when this polymer is spun to produce an inorganic fiber, the precursor yarn is fused at the time of infusibility. It is difficult to obtain an inorganic fiber having high strength and elastic modulus. Further, if the melting point is higher than 400 ° C., the softening and flowing temperature becomes high, and the polymer is decomposed, which is not preferable.

The metal-containing polycyclic aromatic polymer contains 10 to 98% of an insoluble matter in an organic solvent such as benzene, toluene, xylene, and tetrahydrofuran, and has an optical anisotropy degree of 5 to 97% at room temperature. Is preferred.

When the content of the metal-containing polycyclic aromatic polymer insoluble in the above organic solvent is less than 10% or the degree of optical anisotropy is less than 5%, particularly when the polymer is melt-spun to form a fiber, the fiber axis of the mesophase is Almost no orientation occurs in the direction, and thus the obtained precursor fiber is infusibilized, and even if it is fired, only fibers having low strength and low elastic modulus can be obtained.
% Or the optical anisotropy degree is more than 97%, the mesophase in the polymer becomes excessive and the polymer may need high temperature for softening and flowing, which may cause difficulty in molding. .

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

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

One of the raw materials, organosilicon polymer, is a bonding unit (Si-C
H _2), or binding units (Si-CH ₂₎ and the coupling unit (Si-Si)
The ratio of the total number of bonding units (Si—CH ₂ ) to the total number of bonding units (Si—Si) is in the range of 1: 0 to 20, and the compound can be synthesized by a known method. For example, the organosilicon polymer is obtained by heating polydimethylsilane obtained by the reaction of dimethyldichlorosilane and metallic sodium to 400 ° C. or higher in an inert gas.

The weight average molecular weight (Mw) of the organosilicon polymer is generally
Those having an Mw of 400 to 800 and an Mw of 300 to 1000 are particularly preferable when the purpose is to produce inorganic fibers.

The polycyclic aromatic compound which is another raw material is pitch obtained from petroleum or coals, and generally, one having a high aromaticity is suitable, for example, fluid catalytic cracking residual oil of petroleum. (FCC slurry oil) or pitch obtained by removing light fraction from heat-treated oil, pitch obtained from naphthatar, coal-based pitch such as coal tar pitch, synthetic pitch obtained by heat-treating vinyl chloride, etc. Among these, pitch obtained by removing the light fraction from the fluid catalytic cracking residual oil of petroleum (FCC slurry oil) or its heat-treated oil is particularly preferable.

In the above pitch, there are 5 to 98 components insoluble in organic solvents such as benzene, toluene, xylene, and tetrapydrofuran.
%, Particularly preferably 10 to 80%. When a pitch having an organic solvent insoluble content of less than 5% was used as a raw material, when an inorganic fiber was produced, strength and elastic modulus were low, and a pitch having an organic solvent insoluble content of more than 98% was used as a raw material. In this case, the precursor polymer (1) described below has a high melting point, which is not preferable.

The weight average molecular weight of this pitch is 100 to 3000. The weight average molecular weight is a value determined as follows. That is,
If the pitch does not contain organic solvent insoluble matter, perform gel permeation chromatograph (GPC) measurement as it is,
When the pitch contains an organic solvent insoluble matter, it is subjected to hydrogenation treatment under mild conditions to change the organic solvent insoluble matter to an organic solvent soluble ingredient, and then perform GPC measurement. The weight average molecular weight of the polymer containing the organic solvent insoluble matter is a value obtained by performing the same treatment as described above.

The ratio of the pitch used is 50 to 4 per 100 parts of the organosilicon polymer.
It is preferably 900 parts. When the proportion of the pitch component used is excessively small, the amount of the organosilicon component increases, the compatibility with the mesophase polycyclic aromatic compound deteriorates, the uniformity during melting is impaired, and the inorganic material with high strength and high elastic modulus is used. No fibers or composites can be obtained. On the other hand, if the proportion is too large, the amount of the organosilicon polymer component is too small, so that the compatibility of the inorganic material produced from the polymer of the present invention with the matrix and the oxidation resistance are deteriorated.

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. .

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

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 MX ₄ , M is at least one element selected from Ti, Zr and Hf, and X can be bonded to silicon of the precursor polymer (1) directly or through an oxygen atom by condensation. There is no particular limitation as long as it is a halogen atom, an alkoxy group or a complex-forming group such as β-diketone.

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. And gelation occurs, the precursor polymer (1) itself condenses to a high molecular weight, or MX ₄ is volatilized in some cases, which is not preferred. As an example, M is Ti and X is OC ₄ H ₉
In the case of, the reaction temperature is suitably 200 to 400 ° C.

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.

The metal M can be bonded to the silicon atom of the precursor polymer (1) in a side chain form by a bonding mode such as —MX ₃ or —O—MX ₃ , or directly to the silicon atom of the precursor polymer (1). Alternatively, a bonding mode of crosslinking via oxygen may be adopted.

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. .

The random copolymer (2) and the mesophase polycyclic aromatic compound are heated and / or melted by heating to prepare a metal-containing polycyclic aromatic polymer.

The mesophase polycyclic aromatic compound is prepared, for example, by subjecting a petroleum-based or coal-based pitch to heating at a temperature of 300 to 500 ° C. in an inert gas to carry out polycondensation while removing a soft fraction produced. You can If the polycondensation reaction temperature is too low, the condensed ring will not grow sufficiently, and if the temperature is too high, the infusible product will be violently produced due to coking.

The above-mentioned mesophase polycyclic aromatic compound generally has a melting point in the range of 200 to 400 ° C., and has a weight average molecular weight of 200.
~ 10,000.

Among the mesophase polycyclic aromatic compounds, 20-100
%, Especially 40-100% optical anisotropy, 30-100%
Of those containing an insoluble matter in benzene, toluene, xylene or tetrahydrofuran is particularly preferable for obtaining an inorganic fiber having excellent mechanical performance.

The use ratio of the mesophase polycyclic aromatic compound is preferably 5 to 50000 per 100 parts of the random copolymer (2).
Parts, more preferably 5 to 10,000, and less than 5 parts,
Due to the lack of mesophase content in the resulting polymer, it is not possible to obtain highly elastic fibers or moldings even if the obtained polymer is mineralized, and in the case of more than 50,000 parts, the silicon component is insufficient. Even if the polymer is made inorganic, properties such as wettability with respect to the matrix and oxidation resistance are not sufficiently exhibited.

The random copolymer (2) and the mesophase polycyclic aromatic compound are heated and reacted and / or melted at 200 to 500 ° C. so that at least a part of the random copolymer (2) is a mesophase polycyclic aromatic compound. A metal-containing polycyclic aromatic polymer bound with is obtained. However, the term "bond" as used herein means a chemical bond between silicon and carbon of the polycyclic aromatic compound and / or an optically isotropic pitch portion in the random copolymer (2) and the mesophase polycyclic aromatic compound. It means physical coupling such as van der Waals coupling between.

When the melt-mixing temperature is lower than 200 ° C, an infusible portion is generated,
The system becomes heterogeneous, and if the melt-mixing temperature is higher than 500 ° C, the condensation reaction will proceed violently, the resulting polymer will have a high melting point, and the fluidity of the polymer will be lost. Preparation of a metal-containing polycyclic aromatic polymer The way to do
In addition to the method described above, a method of reacting an organosilicon polymer with pitch, adding mesophase pitch and MX ₄ simultaneously or sequentially to the obtained product, and further reacting, is also possible.

(Effect) Since the metal-containing polycyclic aromatic polymer according to the present invention contains a transition metal-containing organosilicon copolymer and a mesophase polycyclic aromatic compound in the polymer, the polymer is melt-spun, infusible, By firing, amorphous and / or Si, M, C, and O are formed on the ultrafine graphite crystal.
Or β-SiC, MC, solid solution of β-SiC and MC, and MC _1- x
(0 <X <1) each crystal ultrafine particle and amorphous SiOy (0 <
It is possible to obtain a carbon-based inorganic fiber having a structure in which an aggregate of y ≦ 2) and MOz (0 <z ≦ 2) is dispersed, which has high strength and elasticity and which is excellent in wettability with a plastic. In this way, since there has been no fiber that can satisfy both mechanical properties and wettability with plastic at the same time,
There are great expectations for the development of applications for FRP. Further, the fiber according to the present invention enables use of the carbon-based fiber in a high temperature oxidizing atmosphere, and by molding the polymer of the present invention, the oxidation-resistant carbon-based material and the fiber-reinforced ceramic (FR
It can be used as a matrix for C). Also,
The present invention greatly contributes from the viewpoint of effective use of pitch.

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

Reference Example 1 (Production 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 of pitch raw material) Among petroleum fractions, high-boiling substances of light oil or higher 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 ratio of 0.55 by nuclear magnetic resonance analysis.

Example 1 (First Step) 500 g of the FCC slurry oil obtained in Reference Example 2 was heated at 450 ° C. for 1 hour under a nitrogen gas stream at a rate of 1 / min, the distillate was distilled off at the same temperature, and the residue was heated to 200 ° C. At hot temperature, the infusible part was removed at the same temperature to obtain 225 g of the soft component 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 give 39 g of the precursor polymer (1).
Got

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,
38 g of a 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 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 to remove the infusible part at the same temperature. Then, 180 g of a light component removal pitch was obtained.

180 g of the obtained pitch was subjected to polycondensation at 400 ° C. for 7 hours in a nitrogen stream while removing the light components produced by the reaction to obtain a heat-treated pitch of 85 g.

This heat treatment pitch has a melting point of 268 ° C, xylene insoluble content of 92%,
It was a mesophase polycyclic aromatic compound containing 12% quinoline-insoluble matter and having an optical anisotropy of 89% by observation of the polished surface with a polarizing microscope.

(Fourth step) 15 g of the random copolymer (2) obtained in the second step and 75 g of the mesophase polycyclic aromatic compound obtained in the third step were mixed and heated under a nitrogen atmosphere at 310 ° C. for 1 hour to obtain a uniform mixture. A metal-containing polycyclic aromatic polymer in a state was obtained.

This metal-containing polycyclic aromatic polymer has a degree of optical anisotropy.
66%, xylene insolubles 74%, melting point 270 ℃, hydrogenated under mild conditions, the weight average molecular weight (Mw) was measured by gel permeation chromatography (GPC), Mw = It was 880.

This metal-containing polycyclic aromatic polymer is heated to 1200 ° C. in air, and the obtained ash is subjected to alkali melting and hydrochloric acid treatment,
After dissolving in water, the concentration of silicon and titanium in the aqueous solution was measured using a high frequency plasma emission spectrophotometer (ICP). The content of silicon and titanium in the metal-containing polycyclic aromatic polymer was 3.1%. And 0%.

Examples 2 to 7 Pitch, organosilicon polymer and Ti (OC ₈ H ₁₇ ) ₄ charging ratio and copolymerization conditions in the first step and the second step of Example 1, heat treatment conditions in the second step, and the third step Select various charging ratios and melt mixing (melt condensation) conditions in the process,
A metal-containing polycyclic aromatic polymer was obtained. The results are shown in Table 1 together with the results of Example 1. The metal-containing polycyclic aromatic polymer obtained in any of the examples contained silicon in an amount of 0.4 to 2
2.0% Further, it contained 0.01 to 3.5% of titanium and had optical anisotropy.

Comparative Example 1 (First Step) 200 g of the FCC slurry oil obtained in Reference Example 2 was heated at 420 ° C. for 2 hours under a nitrogen gas flow of 1 / min. After heating, the light fraction at the same temperature was distilled off to obtain 114 g of light fraction removal pitch. The obtained pitch was placed in xylene 500 at 130 ° C.
After dissolving 69 ml of xylene and removing 69 g of xylene-insoluble matter, 45 g of the xylene-soluble part 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. Let
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 at 400 ° C. for 6 hours in an inert atmosphere to give a heat-treated pitch of 41 g.
Got

(Third step) 30 g of the copolymer obtained in the first step and the heat pitch 6 obtained in the second step
0 g was heated and mixed at 300 ° C. for 2.5 hours.

Weight average molecular weight (Mw) of the product obtained by the above reaction
Was 1750 and the silicon content was 10.5%, but the melting point was 198 ° C.
It was an optically isotropic polymer containing 11% of xylene-insoluble matter.

Comparative Example 2 50 g of the organosilicon polymer obtained in Reference Example 1 was added to 100 g of the pitch obtained in Example 1 and reacted at 400 ° C. for 6 hours to obtain 79 g of a precursor polymer. The obtained copolymer has a melting point of 252 ° C and a silicon content of 1
At 5%, the average weight molecular weight (Mw) was 1400, it contained no xylene insolubles and no mesophase portion was present.

Example 8 To 39 g of the precursor polymer (1) obtained in Example 1, an ethanol-xylene solution (1.5%) of 5.4 g of tetrakisacetylacetonatozirconium was added, and after distilling off the solvent, polymerization was carried out at 250 ° C. for 1 hour. A random copolymer (2) of g was obtained.

20 g of this random copolymer (2) and 50 g of the mesophase polycyclic aromatic compound prepared in the same manner as in Example 1 were heated at 350 ° C.
And melt-mixed for 1 hour to obtain 67 g of a metal-containing polycyclic aromatic polymer.

This metal-containing polycyclic aromatic polymer has a melting point of 274 ° C.
% Xylene insoluble matter, average weight molecular weight 1050
Met.

The contents of silicon and zirconium in this polymer were 4.1% and 0.8%, respectively.

Example 9 In the same manner as in Example 1, 57 g of the precursor polymer (1) was obtained from 60 g of the pitch obtained in Example 1 and 40 g of the organosilicon polymer.

Hafnium chloride 7.2 is added to 40 g of this precursor copolymer (1).
Ethanol-xylene solution (g) was added, and xylene was distilled off, followed by polymerization at 250 ° C. for 1 hour to obtain 4.35 g of random copolymer (2).

20 g of this random copolymer (2) and 80 g of the mesophase polycyclic aromatic compound were melt mixed at 350 ° C. for 1 hour to obtain 96 g of a metal-containing polycyclic aromatic polymer.

This metal-containing polycyclic aromatic polymer has a melting point of 280 ° C.
% Xylene insoluble matter, average weight molecular weight 98
It was 0.

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

Example 10 (First Step) 700 g of the FCC slurry oil obtained in Reference Example 2 was heated at 450 ° C. for 0.5 hours under a nitrogen gas flow of 2 / min, and the distillate was distilled off at the same temperature and the residue was heated to 200 ° C. At hot temperature, the infusible portion was removed at the same temperature to obtain 200 g of light component removal pitch.

The light content removal pitch was an optically isotropic pitch containing 25% of xylene-insoluble matter.

25 g of the organosilicon polymer obtained in Reference Example 1 and 20 ml of xylene were added to 57 g of this pitch, the temperature was raised with stirring, and xylene was distilled off and reacted at 400 ° C. for 4 hours to give 57.4 g of the precursor polymer (1). Got

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) 57.4 g of the precursor polymer (1) was added to tetraoctoxytitanium [Ti
(OC ₈ H ₁₇ ) ₄ ] 3.87 g of xylene solution (25% xylene solution 15.5 g) was added, and xylene was distilled off, followed by reaction at 340 ° C. for 1 hour to obtain 56 g of a random copolymer (2).

This polymer does not contain a xylene-insoluble part and has a weight average molecular weight of
It had a melting point of 258 ° C and a softening point of 292 ° C.

(Third step) 180 g of the light content removal pitch obtained in the same manner as in the first step was removed under a nitrogen stream while removing the light content produced by the reaction.
Polycondensation was carried out at 400 ° C. for 8 hours to obtain 97.2 g of heat treatment pitch.

This heat-treated pitch contains a melting point of 263 ° C, a softening point of 308 ° C, xylene insoluble content of 77%, and quinoline insoluble content of 31%. It was a family polymer.

(Fourth step) 6.4 g of the random copolymer (2) obtained in the second step and 90 g of the mesophase polycyclic aromatic compound obtained in the third step are mixed and heated under a nitrogen atmosphere at 380 ° C. for 1 hour to obtain a uniform mixture. A metal-containing polycyclic aromatic polymer in a stable state was obtained.

This metal-containing polycyclic aromatic polymer has a degree of optical anisotropy.
62%, xylene insoluble content 68%, melting point 264 ℃, softening point 3
It was 07 ° C., hydrogenated under mild conditions, and the weight average molecular weight (Mw) was measured by gel permeation chromatography (GPC). As a result, Mw was 860.

This metal-containing polycyclic aromatic polymer is heated to 1200 ° C. in air, the obtained ash is subjected to alkali melting treatment and hydrochloric acid treatment, dissolved in water, and then the aqueous solution thereof is subjected to a high frequency plasma emission spectrophotometer (ICP The content of silicon and titanium in the metal-containing polycyclic aromatic polymer was 0.91% and 0.06%.

Examples 11 to 18 Pitch, organosilicon polymer and Ti (OC ₈ H ₁₇ ) ₄ charging ratio and copolymerization conditions in the first step and second step of Example 10, heat treatment conditions in the third step, and the fourth step Select various charging ratios and melt mixing (melt condensation) conditions in the process,
A metal-containing polycyclic aromatic polymer was obtained. The results are shown in Table 2 together with the results of Example 10. The metal-containing polycyclic aromatic polymer obtained in any of the examples had optical anisotropy.

Example 19 To 39 g of the precursor polymer (1) obtained in Example 10, an ethanol-xylene solution (1.5%) of 5.4 g of tetrakisacetylacetonatozirconium was added, the solvent was distilled off, and the mixture was polymerized at 250 ° C. for 1 hour. A random copolymer (2) of g was obtained.

20 g of this random copolymer (2) and 50 g of mesophase polycyclic aromatic compound prepared in the same manner as in Example 10 were heated at 360 ° C.
And melt-mixed for 1 hour to obtain 67 g of a metal-containing polycyclic aromatic polymer.

This metal-containing polycyclic aromatic polymer has a melting point of 26. It contained xylene insoluble matter at 54% at 6 ° C and had an average weight molecular weight of 1010.

The contents of silicon and zirconium in this polymer were 4.1% and 0.8%, respectively.

Example 20 57 g of the precursor copolymer (1) was obtained in the same manner as in Example 10 from the pitch of 60 g and the organosilicon polymer of 40 g obtained in Example 10.

Hafnium chloride 7.2 is added to 40 g of this precursor copolymer (1).
Ethanol-xylene solution (g) was added, ethanol and xylene were distilled off, and the mixture was polymerized at 250 ° C. for 1 hour to obtain 43.5 g of random copolymer (2).

20 g of this polymer and 80 g of mesophase polycyclic aromatic compound
The mixture was melt-mixed at 350 ° C. for 1 hour to obtain 96 g of a metal-containing polycyclic aromatic polymer.

This metal-containing polycyclic aromatic polymer has a melting point of 269 ° C., 60
% Xylene insoluble matter, average weight molecular weight 930
Met.

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

Example 21 The metal-containing polycyclic aromatic polymer obtained in Example 1, Example 3, Example 4, Example 8 and Example 9 was used as a spinning dope and melt-spun using a nozzle having a diameter of 0.15 mm. The obtained precursor fiber was infusible at 300 ° C. under air flow, and fired at 1300 ° C. under an argon stream to obtain a carbonaceous inorganic fiber. The yarn diameter, tensile strength, and tensile elastic modulus of this fiber are 9.5 μ, 325 kg / mm ² , 32 t / mm ² , respectively in the case of the dope of Example 1.
In the case of the dope of Example 3, 9.0μ, 318 kg / mm ² , 36 t / mm
² , in the case of the dope of Example 4, 8.6μ, 360kg / mm ² , 33t
/ mm ² , in the case of the dope of Example 8, 11.5μ, 340 kg / m
m ² , 34 t / mm ² , in the case of the dope of Example 9, 12.0 μ, 328
The values were kg / mm ² and 38t / mm ² .

As a result of observing the cross section of the fiber with a scanning electron microscope, all the fibers have a random-radial structure spiral onion structure based on a coral-like random structure radial,
It was shown that the mesophase component in the dope was oriented along the fiber axis during spinning, infusibilization and firing.

Example 22 The metal-containing polycyclic aromatic polymer obtained in Example 10, Example 11, Example 18, Example 19 and Example 20 was used as a spinning dope, and melt spinning was performed using a nozzle having a diameter of 0.15 mm. The obtained precursor fiber was made infusible at 300 ° C. under air flow, and fired at 1300 ° C. under an argon stream to obtain a carbonaceous inorganic fiber. The yarn diameter, tensile strength, and tensile modulus of this fiber are, respectively, 7.5 μ, 358 kg / mm ² , 32 t / mm ² , in the case of the dope of Example 10.
In the case of the dope of Example 11, 9.5μ, 325kg / mm ² , 32t / mm
² , in the case of the dope of Example 18, 8.5μ, 362kg / mm ² , 34t
/ mm ² , in the case of the dope of Example 19, 11.0μ, 350kg / m
m ² , 34 t / mm ² , in the case of the dope of Example 20, 12.0 μ, 340
The values were kg / mm ² and 38t / 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 21 to obtain a fired yarn. The thread diameter, tensile strength, and tensile elastic modulus of each fiber are 11μ, 120 kg / mm ² , 7.5 t / mm ² in the case of the dope of Comparative Example 1 and 10.5 μ in the case of the dope of Comparative Example 2, respectively. , 85 kg / mm ² , and 5.7 t / mm ² .

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

Front page continuation (72) Inventor Masaki Shibuya 5 1978, Ogushi, Ube City, Yamaguchi Prefecture 5 Yube Hokura, Examiner, Ube Laboratory, Ube Industries, Ltd. (56) Reference 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 in the side chain of a silicon atom. Group having a side chain group selected from the group consisting of a phenyl group and a silyl group, the ratio of the total number of bonds (Si-CH ₂ ) to the total number of bond units (Si-Si) is in the range of 1: 0 to 20. And a transition metal-containing organosilicon polymer unit in which 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, From (B) a polycyclic aromatic compound unit in a mesophase state in which the skeleton component is mainly a condensed ring structure, and (C) a polycyclic aromatic compound unit in which the skeleton component is mainly a condensed ring structure and having an optically isotropic phase, Therefore, the number of silicon atoms in (A) is small. At least some
A random copolymer is formed by binding the carbon atom of the aromatic ring of (B) and / or (C) through a silicon-carbon linking group, and forms the random copolymer of (A), (B) and The weight ratio with the total of (C) is 1: 0.5 to 5000, the above (B)
And (C) have a weight ratio of 1: 0.02 to 4, a silicon atom content of 0.01 to 30 wt%, and a content of at least one atom selected from the group consisting of titanium, zirconium, and hafnium of 0.005. The metal-containing polycyclic aromatic polymer is characterized by having a content of -10% by weight and a weight average molecular weight of 200-11,000. 2. A bonding unit (Si—CH ₂ ), or a bonding unit (Si—CH ₂ ) and a bonding unit (Si—Si), which are mainly composed of a hydrogen atom and a lower alkyl group in the side chain of silicon. A transition metal-containing organic compound having a phenyl group or a silyl group, in which at least one atom selected from Ti, Zr and Hf is bonded directly or through an oxygen atom to the silicon atom of the main skeleton consisting of the above-mentioned bond unit. At least a part of silicon atoms of a silicon polymer is a petroleum-based pitch or a heat-treated product thereof, and is a random bond in which carbon of an aromatic ring of a polycyclic aromatic compound obtained from pitch containing an organic solvent insoluble component is bonded. A copolymer and 2) a polycyclic aromatic compound obtained from a petroleum-based or coal-based pitch and having a mesophase or both a mesophase and an optically isotropic phase are heated at a temperature in the range of 200 to 500 ° C. Reaction and / or addition A method for producing a metal-containing polycyclic aromatic polymer, which comprises heat melting.