JPS62215016A - Sic-c based inorganic filament and production thereof - Google Patents

Abstract

PURPOSE:To obtain the titled fibers, having improved heat resistance and mechanical characteristic and suitable as a reinforcing material for composite materials, by spinning a specific organopolyarylsilane, infusibilizing the resultant filaments and firing the infusibilized filaments in an unreactive atmosphere at a high temperature. CONSTITUTION:An organopolyarylsilane, obtained by randomly linking aromatic ring segments having a skeletal part consisting of an aromatic ring condensed structure to organosilane segments having a skeletal part consisting of carbosilane and polysilane structure through silicon-carbon linking groups and soluble in organic solvents is spun into filaments, which are then infusibilized and fired in an unreactive atmosphere at 800-3,000 deg.C to afford the aimed filaments, containing 5-55wt% silicon, 40-95wt% carbon and 0.01-15wt% oxygen, exhibiting 10-10<-3>OMEGA.cm volume resistivity and having improved heat- resistant strength and antioxidant property.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is a novel fiber produced by spinning SiC-C continuous inorganic fibers, specifically organopolyarylsilane, insolubilizing it, and then firing it in a non-reactive atmosphere. The present invention relates to a SiC-C continuous inorganic fiber and a method for producing the same.

(Prior Art) Conventionally known SiC-based continuous inorganic fibers are made from polymers obtained by thermally polymerizing organosilicon compounds.
JP 51-139929, JP 51-130324, JP 51-130325, JP 51-149925,
No. 51-149926, No. 51-147623, No. 51-147624, No. 52-1136, No. 52-
No. 5321, No. 52-31126, No. 52-1035
No. 29, No. 52-59724, No. 52-63427, No. 52-70122, No. 52-96237, No. 5
It is disclosed in the following publications: No. 2-103529, No. 53-103025, and No. 54-82435. On the other hand, carbon fibers are obtained using rayon, polyacrylonitrile, pitch, etc. as raw materials, and numerous patent applications have been filed regarding these fibers, their manufacturing methods, and applications, and they are now being mass-produced industrially. However, although the former has excellent heat resistance, oxidation resistance, and composite properties with metal, it has low electrical conductivity and a volume resistivity of 102Ω・1.
In addition, in terms of mechanical properties, for example, controlling the elastic modulus depends on the firing temperature, it is almost impossible to control quality by changing the composition, and it is also expensive. There were various drawbacks, such as the fact that On the other hand, the latter has high heat resistance and electrical conductivity, and has excellent properties in combination with plastics, but has poor air oxidation resistance, and has problems in terms of reactivity when combined with metals.
In particular, when pitch is used as a raw material, it is necessary to use specially treated pitch in order to obtain fibers with excellent properties, which is not necessarily economical.

(Problems to be Solved by the Invention) The present invention provides an excellent new inorganic fiber that overcomes the drawbacks of the conventional SiC fibers and carbon fibers, has new mechanical and electrical properties, etc. The purpose is to provide the following.

The present inventors have separately invented and filed a patent application for organopolyarylsilane, which is a co-thermal decomposition product of polysilane and pitch. By producing SiC-C continuous inorganic fibers using arylsilane,
The above objects of the present invention have been successfully achieved. That is, the fibers obtained by firing fibers spun using the organopolyarylsilane as a raw material have electrical conductivity comparable to that of SiC fibers and carbon fibers, and the composition can be freely controlled. It was confirmed that not only the carbon fibers and mechanical properties can be controlled over a wide range, but also that they have superior air oxidation resistance compared to carbon fibers, and based on this, the present invention was completed.

(Means for Solving the Problems) In the method of the present invention, an aromatic ring segment whose skeleton portion is mainly composed of an aromatic condensed ring structure and an organosilane segment whose skeleton portion is mainly composed of a carbosilane and polysilane structure are silicon-carbon linking groups. A spinning solution of organopolyarylsilane, which is randomly bonded through organic solvents and is soluble in organic solvents, is prepared and spun, the resulting spun fibers are made infusible, and the infusible fibers are placed in a non-reactive atmosphere, For example, in a vacuum or inert gas atmosphere, 800 to 3000
This is a method for producing SiC-C continuous inorganic fibers, which is characterized by firing at a temperature range of .degree.

Further, according to the above-mentioned method of the present invention, - 5 to 55% by weight of molecules consisting of amorphous and/or crystalline carbon and amorphous and/or crystalline SiC as main constituents;
of silicon, 40 to 95 Nx carbon and 0.01 to 1
A continuous SiC-C system having a composition containing 5% by weight of 2% oxygen, having excellent heat resistance and oxidation resistance, and exhibiting a volume resistivity of 10 to 10-3 Ω. Inorganic fibers are provided.

The present invention will be explained in more detail below.

The above-mentioned organopolyarylsilane, which is a starting material used in the method of the present invention, can be obtained by mixing polysilane and pinch soluble in an organic solvent, and heating the mixture in an inert atmosphere to cause cothermal decomposition and condensation. This polysilane has the following structure and may be cyclic or branched.

It is sufficient if n≧2, and R1 and R2 are each hydrogen, halogen, a lower alkyl group having up to 6 carbon atoms, or an aryl group having up to 12 carbon atoms. Particularly suitable polysilanes are R1 and Rt. The polysilane is a polysilane in which 50% or more are methyl groups, or, when a mixture of polysilanes is used, all R and 50X or more of R2 are methyl groups. These polysilanes are synthesized by any known method.

Furthermore, pitch, which is another raw material used to produce organopolyarylsilane, which is the starting material for the method of the present invention, is an aromatic condensed ring obtained when thermally decomposing organic substances such as coal and petroleum. It is a solid or semi-solid material whose main skeleton is, for example, coal-based pitch or petroleum-based pitch can be used. The pitch is preferably one that is soluble in common organic solvents such as benzene, toluene, xylene, tetrahydrofuran, and the like. Of course, pitch containing components insoluble in the solvent can also be used, but when removing solvent-insoluble impurities from the polymer produced after synthesis, a solvent-insoluble product generated from the components in the pitch that is insoluble in the solvent is removed. is also removed along with impurities. Furthermore, as will be described later, the yield of synthesis is reduced by these insoluble components. Further, as a pitch analog, a compound having an aromatic condensed ring, such as tar that is liquid at room temperature, can also be used. It is also possible to use isolated aromatic compounds, but this is not economical.

In the above method, a mixture of 2 to 500 parts by weight of the pinch to 100 parts by weight of at least one of the polysilanes is heated in an atmosphere inert to the reaction to carry out co-thermal decomposition condensation. let

Thus, an aromatic ring segment whose skeleton part is mainly composed of an aromatic condensed ring structure and an organosilane segment whose skeleton part is mainly composed of carbosilane and polysilane structures are randomly bonded via silicon-carbon linking groups, and the organic solvent Organopolyarylsilanes are provided that are soluble in .

The most preferred embodiment of the above method is to carry out the cothermal decomposition and condensation reaction of the mixture in both the liquid phase and the gas phase. In other words, the reactor includes a reaction vessel in which the reaction is carried out in the liquid phase, and a vapor of the mixture produced in the reaction vessel and the vapor of low-boiling components produced by thermal decomposition of the mixture, which is maintained or heated to a temperature higher than the reaction temperature in the reaction vessel. It consists of a reaction tower in which the reaction is carried out in the gas phase, and the vapor and products that have passed through the reaction tower are cooled and returned to the reaction vessel.

In other words, in the method for producing organopolyarylsilane, which is the starting material of the present invention, the thermal decomposition condensation is carried out in both the liquid phase and the gas phase. This solution solves the problem of low yield of polymer due to the presence of low molecular weight gas phase part during the synthesis of polycarbosilane, which was carried out by A silane polymer is obtained.

In the above method, it is necessary to carry out the cothermal decomposition and condensation in an atmosphere of a gas inert to the reaction, and for example, nitrogen, argon, etc. are suitable.

Further, the reaction is preferably carried out under a gas stream at normal pressure, and consideration is desired to prevent temperature rise and pressure rise due to gas such as hydrogen generated during the reaction.

In addition, the heating temperature is 300 to 500°C in the reaction vessel, that is, the part where the reaction takes place in the liquid phase. Below 300°C, the thermal decomposition and condensation of the raw materials will hardly proceed, and above 500°C, the thermal decomposition and condensation of the products will not proceed. Gelation may occur, which is undesirable.

The temperature of the reaction tower is 300 to 800°C, and this temperature varies depending on the type of raw material, and the lower the boiling point of polysilane or the thermal decomposition product of polysilane, the higher the temperature must be, but in general, at 800°C or higher, the temperature inside the reaction tower At temperatures below 300°C, reflux occurs due to cooling, and effective thermal decomposition does not occur, which is undesirable as it also lowers the temperature in the reaction vessel, at least exceeding the temperature in the reaction vessel. It is desirable to keep it.

Furthermore, although the reaction time in the above method is usually completed in a relatively short time, such as 1 to 10 hours after reaching a predetermined temperature, it may take a longer time depending on the raw material.

The polymer obtained by the above-mentioned cothermal decomposition condensation can be purified by dissolving it in a solvent and removing insoluble matter by filtration.If necessary, it can be purified by removing the solvent. Molecular weight can be adjusted by removing components by distillation or fractionating with a solvent.

An important and novel feature of the organopolyarylsilane obtained in this way is that an organosilane polymer segment having a carbosilane or polysilane skeleton, which is inherently poorly compatible, and an aromatic ring segment of pitch having an aromatic condensed ring skeleton are combined together. They are randomly bonded and included in one molecule using a method called thermal decomposition condensation. This is the reason why uniform fibers can be obtained in the spinning process described below, and has made it possible to synthesize SiC-C continuous inorganic fibers. The resulting polymer is a number-average molecule! 500 to 10,000, the residual rate is high when fired in a non-oxidizing atmosphere.

In the method of the present invention, the process of forming the organopolyarylsilane polymer into fibers consists of a spinning process, an infusible process, and a firing process.

First, in the spinning step, the polymer is heated and melted to create a spinning dope, which is then spun using a commonly used melt spinning device. The temperature of the spinning dope during spinning varies depending on the softening temperature of the raw material polymer, but in the temperature range of 100 to 400°C, fibers with a thin diameter can be obtained by increasing the winding speed. is 50-5000
Good results are obtained in the m/min range. In addition to the melt spinning method, the spinning step of the production method of the present invention includes dissolving the polymer in a solvent such as benzene or toluene to obtain a spinning stock solution.
Although spinning can be carried out using ordinary dry spinning equipment, melt spinning is easier.

In the spinning process of the method of the present invention, since the above-mentioned organopolyarylsilane polymer is used, for example, when blend-spinning is attempted by mixing an organosilicon polymer and pitch, the compatibility between them is low. Problems such as not being able to uniformly mix the fibers at the molecular level and producing non-uniform fibers, but also, in extreme cases, making it impossible to spin, do not occur. Moreover, when a mixture is used as a raw material, the characteristics of each must be adjusted to suit the subsequent infusibility step and firing step, and this treatment further reduces their compatibility.

Next, in the infusible step in the method of the present invention, the spun fibers are oxidized in an oxidizing atmosphere at a temperature ranging from room temperature to 350° C. to make the spun fibers infusible. The purpose of this oxidation treatment is to crosslink the raw material molecules that form the spun fibers,
This is to prevent the fibers from fusing in the firing process described later, and the oxidizing atmosphere includes air, oxygen, ozone,
Selected from halogen gases. A gas atmosphere containing one or more types of gas is preferable, and temperatures exceeding 350° C. are not preferable because oxidation proceeds too much.

The time for the oxidation treatment is related to the temperature, and takes a short time in a high temperature range and a long time in a low temperature range, but the heating rate to a specified temperature is 5℃ to 50℃/hour, and A holding time of 2 hours or less is often sufficient.

In the infusibility step of the method of the present invention, in addition to the method of treating in an oxidizing atmosphere, the spun fibers are irradiated with ultraviolet rays in an oxidizing atmosphere or a non-oxidizing atmosphere at a temperature range of room temperature to 350°C. It can be made infusible by irradiation with radiation or electron beam.

When this irradiation is carried out in the oxidizing atmosphere, oxidation is promoted, which is advantageous in the case of polymers that oxidize slowly. The purpose of irradiation in a non-oxidizing atmosphere such as an inert gas or vacuum is to crosslink and infusible the polymer molecules that form the spun fibers, and in particular to minimize the amount of oxygen in the fibers. is suitably 106 to 10'T.

Next, in the firing step of the method of the present invention, the infusible fibers are fired at a temperature range of 800 to 3000°C, and SiC-
C-based continuous inorganic fiber.

The calcination is performed in a non-reactive atmosphere, such as a vacuum or an inert gas atmosphere, at a temperature range of 800 to 3000°C, under tension or no tension, and the polymer forming the infusible fiber undergoes a thermal polycondensation reaction. Easily volatile components are released by thermal decomposition reaction. Easily volatile components are mainly produced at 300 to 800°C, and for this reason, the infusible fibers may shrink and bend, but this bending can be prevented by applying tension during firing. can. Furthermore, the effect of tension at high temperatures is advantageous, especially in the case of fibers with a high carbon content, as it may improve the properties of the fibers. The magnitude of the tension at this time is in the range of 0.01kir~10kg/mm''.If the firing temperature is below 800℃, only a small tension can be applied, but if the firing temperature is above 800℃, the strength of the fiber is sufficiently high, so a large tension can be applied. In general, good results can be obtained with a tension in the above range.The above firing is performed in an atmosphere,
A multi-stage firing method in which conditions such as temperature and time are changed can also be used.

SiC-C manufactured by the method of the present invention explained above
The composition of the continuous inorganic fiber is Si, 5 to 55 layers x;
C, 40-95% by weight: 0.0.01-15% by weight.

When the firing temperature is relatively low, trace amounts of hydrogen may be included, and impurities such as nitrogen and sulfur may also be included. Fibers with such a composition are mainly formed of amorphous and/or crystalline carbon and amorphous and/or crystalline SiC, and although there is no clear distinction between amorphous and crystalline, The average size of crystallites forming fibers gradually increases as the firing temperature increases.

In addition, the average size of crystallites is affected by the size of the segments forming the raw material polymer, and when the aromatic ring segment is large and the organosilane segment is small, the size of SiC crystallites is so small that it cannot be calculated. However, when the organosilane segment is large, SiC becomes β-
The diffraction line of SiC crystal is shown. For example, 5 parts by weight of toluene-soluble petroleum pitch is added to 100 parts by weight of polydimethylsilane, the synthesized polymer is spun,
After being infusible for a period of time, the fibers obtained by firing at 1200°C in vacuum had Si: 51.1 weight 9! , C: 40.0% by weight
, shows a composition of 0:8.9 weight 2, but β in the fired fiber
-The size of SiC crystallites is determined by the firing temperature of 900.1200
．． At 1500°C, they are about 10,30,70 people respectively. Furthermore, at temperatures above 1400°C, oxygen bonded to silicon atoms in the fibers reacts with carbon and is released as a gas, and at the same time, silicon atoms and carbon react to form Si.
In the case of fibers with a large amount of oxygen, the size of the crystallites becomes even thicker.Also, when the temperature exceeds 1000℃, α-SiC is generated.Such crystal growth and phase change has a negative effect on the mechanical properties of the fibers, so when a polymer containing large organosilane segments is used, fibers with excellent mechanical properties can be obtained at a firing temperature of 1800° C. or lower.

On the other hand, in fibers synthesized using polymers with large aromatic ring segments, the thickness of SiC crystallites is smaller than the above value, and on the other hand, it is equivalent to graphite crystals of carbon (00
2) The size of crystallites obtained from diffraction lines increases as the firing temperature increases, but remains below 100 Å.

(for production) Next, the effect of the present invention will be described together with the characteristics of the fiber of the present invention.

The feature of the SiC-C continuous inorganic fiber of the present invention is that it has electrical conductivity and exhibits a volume resistivity in the range of 10 to 10<-3 >[Omega].0. In other words, this value indicates that the volume resistivity of SiC continuous fibers conventionally obtained by firing at 1400°C is 10"Ω・
0 or more, whereas the SiC-
Although the C fiber was fired at 1200℃, it had a resistance of about 1Ω・
cm, which is less than 1/100 that of conventional SiC fibers.

Further, as C9 increases and as the firing temperature increases, this value gradually decreases to about 5×10 −4 Ω·ω. Even if a polymer synthesized by mixing a slight pinch of raw materials is used, this remarkable decrease in volume resistivity is an unexpected effect. For example, when fine carbon powder is mixed into an organosilicon polymer, Even if it were made into fibers, this kind of phenomenon would never occur. As mentioned above, this material is made from a polymer in which aromatic ring segments and organosilane segments are uniformly mixed and bonded at the molecular level, so the structure of the fibers produced by firing is extremely uniform, especially when fired. SiC when the temperature is below 1400℃
Both C and C are amorphous, and the size of each particle is exactly at the molecular level of a polymer, a kind of n
It can be said to be an m-level complex and has a completely new structure.

The low volume resistivity is due to this structure. Furthermore, the SiC-C continuous inorganic fiber of the present invention also has excellent mechanical properties. In particular, the air oxidation resistance is such that carbon fibers obtained from general pitch etc. begin to oxidize at around 350°C.
In contrast, the fibers of the present invention cannot be used at temperatures up to 500°C, especially in the amorphous region due to the presence of SiC.
Even in air oxidation at temperatures above 00°C, the strength decreases slightly in the early stages of oxidation, but after that an oxide film is formed and the decrease in strength stops, allowing it to be used even at high temperatures where conventional carbon fibers cannot be used.

(Example) Next, the present invention will be explained with reference to examples.

Example 1 Toluene-soluble content of petroleum pitch (number average molecular weight 320, carbon content 1i 92.1%) was added to poly(dimethylsilane) obtained by dechlorination condensation of dichlorodimethylsilane with metallic Na in xylene. Mix in various proportions, set the temperature of the reaction tower to 575°C, and reduce the temperature in the reaction vessel (reaction temperature).
Co-thermal decomposition and condensation of the mixture was carried out by setting various values of reaction time and reaction time. After the reaction was completed, insoluble matter was removed by filtration as a toluene solution, then heated to 300° C. in a nitrogen atmosphere, and low molecular weight components were removed by distillation to obtain each polymer. Table 1 shows the synthesis conditions for each polymer.

These polymers were heated and melted at 300 to 350°C and heated to 50°C.
The fiber was spun at a spinning speed of 500 IIlZ from a 0 μm spinneret, then heated in air at a heating rate of 10° C./hour to a predetermined temperature, held for 1 hour to infusible, and then heated to 100° C. in vacuum.
The fibers were heated to 1200° C. at a heating rate of /hour and held for 1 hour to obtain fibers with a diameter of 10 to 15 μm. The mechanical properties of the fibers were determined using gauge length 25, crosshead speed 2 fin/
Measured in minutes. Volume resistivity was also measured. Infusibility temperature, mechanical properties, volume resistivity, and chemical analysis values of fibers (S
i, ClO only) are also shown in Table 1.

Example 2 The polymer of No. 4 synthesized in Example 1 was spun and infusible in the same manner as in Example 1, and heated at a temperature increase rate of 100° C./hour in an argon gas flow of 200 cc/minute. 1000,
Fibers were obtained by firing at 1200°C or 1500°C for 1 hour. The mechanical properties, volume resistivity and chemical analysis values of these fibers are shown in Table 2.

Table 2 Example 3 The lll116 polymer synthesized in Example 1 was spun in the same manner as in Example 1, and then spun at 1.5x in a nitrogen gas atmosphere.
After making it infusible by irradiating it with an electron beam of 1O'r, 200c
After heating to 700°C in an argon gas flow of c/min, it was further heated to 1200°C under the action of a tension of about 4 kg/Tsuru2.
, 2,000 or 2,500°C and held for 1 hour for firing to obtain fibers. Table 3 shows the mechanical properties, volume resistivity, and chemical analysis values of these fibers.

Example 4 20 g of pitch used in Example 1 was combined with 70 g of poly(dimethylsilane) used in Example 1 and hexamethyldisilane Log, and the temperature of the reaction tower was 680°C, the reaction temperature was 400°C, Cothermal decomposition condensation was carried out for a reaction time of 10 hours, and after the reaction was completed, the obtained polymer was treated in the same manner as in Example 1. In addition, 50 g of the pitch used in Example 1 was mixed with 50 g of polysilane obtained by dechlorination condensation of ethylmethyldichlorosilane with metallic Na in xylene, and the temperature of the reaction tower was set to 400°C, the reaction temperature was 400°C, and the reaction was carried out. Cothermal decomposition condensation was carried out for 5 hours, and after the reaction was completed, insoluble matter was removed by filtration as a toluene solution, and the temperature was increased to 300℃/
The polymer obtained by removing low molecular weight components up to the boiling point of 15ml11g by vacuum distillation is designated as 8. In addition, petroleum pitch (carbon content 194.5%, toluene insoluble content 5%) was added to the poly(dimethylsilane) loog used in Example 1.
9.1%) was mixed and subjected to cothermal decomposition and condensation in the same manner as the polymer of No. 1, and the obtained polymer was designated as No. 9. Furthermore, add 3 diphenyldi and chlorosilane to dichlorodimethylsilane.
Toluene soluble content of coal-based pitch (average molecular [280, carbon content ff191.5
%) were mixed and co-thermally decomposed and condensed at a reaction tower temperature of 600°C and a reaction temperature of 350"C1 reaction time of 10 hours.
After the reaction was completed, the polymer obtained by the same treatment as in Example 1 was designated as 11hlo.

These polymers were heated and melted at 280 to 350°C and heated to 50°C.
The fibers were spun from a 0 μm spinneret at a spinning speed of 300 m/min, and then heated in air at a heating rate of 5° C./hour to a predetermined temperature and held for 2 hours to infusible. After that, 200cc/
120°C at a heating rate of 100°C/hour in a nitrogen gas stream of 120 min.
Heat to 0℃ and hold for 1 hour to bake, diameter 12-18
A micrometer fiber was obtained. The mechanical properties, volume resistivity, and chemical analysis values of these fibers are shown in Table 4 together with the infusibility temperature.

Example 5 Example 1 l1h6. The fibers made from the polymer were heat treated in air at 550°C and 600°C for 1 hour each,
The results of examining changes in mechanical properties due to oxidation of fibers are presented in the fifth section.
Shown in the table. This result shows that although the mechanical properties decrease at the beginning of oxidation, they then approach a constant value and the progress of oxidation is suppressed.

Table 5 (Effects of the Invention) As described above, the SiC-C continuous aluminous fiber of the present invention has excellent heat resistance and oxidation resistance, and has a volume resistivity of 10 to 10-
3Ω・G, and has excellent mechanical properties, so it has a wide range of uses, including reinforcing materials for composite materials that utilize these properties, as well as heat-resistant materials and structural materials for electrical and electronic materials, and aerospace and aviation. Conceivable.

Claims (1)

[Claims] 1. Consisting of molecules whose main constituents are amorphous and/or crystalline carbon and amorphous and/or crystalline SiC, 5-55% by weight silicon, 40-95% by weight %
of carbon and 0.01 to 15% by weight of oxygen, and exhibits excellent heat resistance strength and oxidation resistance, as well as a volume resistivity of 10 to 10^-^3 Ωcm. A SiC-C continuous inorganic fiber characterized by: 2. The SiC-C continuous inorganic fiber according to claim 1, which does not substantially contain α-SiC crystals. 3. The SiC-C continuous inorganic fiber according to claim 1 or 2, which contains graphite crystallites having a size of at most 100 Å. 4. The SiC-C continuous inorganic fiber according to claim 1, wherein the constituent carbon and SiC are both amorphous. 5. An aromatic ring segment whose skeleton is mainly composed of an aromatic condensed ring structure and an organosilane segment whose skeleton is mainly composed of carbosilane and polysilane structures are randomly bonded through silicon-carbon linking groups, and 800-30 in a non-reactive atmosphere after spinning and infusible organopolyarylsilane which is soluble.
A method for producing SiC-C continuous inorganic fibers, characterized by firing at a temperature of 00°C. 6. The method for producing a SiC-C continuous inorganic fiber according to claim 5, wherein the aromatic ring segment is derived from pitch soluble in an organic solvent. 7. The SiC-C continuous inorganic material according to claim 5 or 6, wherein the organic solvent is at least one aromatic solvent selected from the group consisting of benzene, toluene, xylene, and tetrahydrofuran. Fiber manufacturing method. 8. Organopolyarylsilane is 500 to 10,000
A method for producing a SiC-C continuous inorganic fiber according to any one of claims 5 to 7, which has a number average molecular weight of 0. 9. The organopolyarylsilane of claims 5 to 8 is a mixture of polysilane and pitch soluble in an organic solvent, which is co-thermally decomposed and condensed by heating in an inert atmosphere. Any method for producing a SiC-C continuous inorganic fiber. 10. Polysilane has a general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (However, n≧2 is an integer, and R_1 and R_2
represents hydrogen, halogen, an alkyl group having up to 6 carbon atoms, or an aryl group having up to 12 carbon atoms, respectively. ) The polysilane is a linear, cyclic or branched polymer having a main chain structure represented by
11. The method for producing a SiC-C continuous inorganic fiber according to claim 10, wherein at least 50% of_1 and R_2 are methyl groups. 12. Pitch 2 to 5 for 100 parts by weight of polysilane
00 parts by weight of the SiC-C continuous inorganic fiber according to any one of claims 9 to 11. 13. S according to any one of claims 9 to 12, wherein the cothermal decomposition condensation reaction is carried out in both a liquid phase and a gas phase.
A method for producing iC-C continuous inorganic fiber. 14. The method for producing SiC-C continuous inorganic fibers according to claim 13, wherein the liquid phase reaction is carried out at 300 to 500°C and the gas phase reaction is carried out at 300 to 800°C. 15. The method for producing SiC-C continuous inorganic fibers according to any one of claims 9 to 14, wherein the co-thermal decomposition and condensation reaction is carried out at normal pressure. 16. The method for producing SiC-C continuous inorganic fibers according to any one of claims 5 to 15, wherein the firing temperature is at most 1800°C. 17. The method for producing SiC-C continuous inorganic fibers according to claim 16, wherein the firing temperature is at most 1400°C.