JP3080104B2 - Thermosetting copolymer and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thermosetting copolymer and a method for producing the same. This copolymer is a copolymer of a thermoplastic silicon-containing polymer and a perhydropolysilazane and exhibits thermosetting properties, so it can be directly converted to ceramics by thermal decomposition, and can be used for ceramic fibers, ceramic coatings, ceramic adhesives, etc. Useful as a precursor polymer.

[0002]

2. Description of the Related Art Silicon carbide is excellent as a structural material, but polycarbosilane, polysilastyrene, polysilane and the like are known as precursor polymers thereof (Ceram. En.
g.Sci.Proc., 97-8, 1988, pp.931-942; JP-A-51-1
26300, 52-74000, 52-112700, etc.).

As precursors of silicon carbide ceramics such as SiC-TiC, polytitanocarbosilane, polyzirconocarbosilane, polydisiylazane, and the like are known (US Pat. Nos. 4,340,619, 4,321,970, and 4,321,970). , 48
2,689, JP-B-2-33734, JP-B-2-33733, JP-B-61-58086 and JP-B-62-61220). On the other hand, polysilazane is known as a precursor of silicon nitride and silicon nitride ceramics, and the present inventors have developed and disclosed it (Japanese Patent Publication No. 63-16325).

[0004]

Since all of the above-mentioned polymers which are precursors of silicon carbide or silicon carbide ceramics are thermoplastic, an infusibilization step is indispensable when producing a ceramic product therefrom. As the infusibilization method, thermal oxidation, steam treatment, γ-ray irradiation, electron beam irradiation, ultraviolet irradiation, halogen treatment, ozone treatment, etc. are known, but the treatment method is complicated, and it is dangerous because it handles radiation, There are problems such as inefficiency and the inclusion of impurities. In particular, oxygen introduced by thermal oxidation causes deterioration of high-temperature characteristics of ceramics.

[0005] Silicon nitride and silicon nitride ceramics are high-temperature structural materials excellent in strength, toughness, etc.
Since silicon carbide can provide a structural material with higher strength, it is expected that by combining silicon nitride and silicon nitride-based ceramics with silicon carbide, ceramics with more excellent properties will be provided. Accordingly, the present invention is to provide a useful polymer as a ceramic precursor that does not require an infusibilization step by converting a thermoplastic polymer into a thermosetting material, especially a composite ceramic in which silicon carbide is combined with silicon nitride. It is an object to provide a polymer useful as a precursor of the polymer.

[0006]

The above object has been achieved by copolymerizing a thermoplastic silicon-containing polymer with a thermosetting perhydropolysilazane.
Further, a metal compound can be added to promote crosslinking. Thus, according to the present invention, the number average molecular weight is 100 to
50,000 perhydropolysilazane block A and polycarbosilane or polysilastic having a number average molecular weight of 100 to 50,000
Ren, polycarbosilastyrene, methylpolysilane,
Phenyl polysilane, polytitanocarbosilane, polysil
Selected from conocarbosilane and polydisiylazane
That a block copolymer having a number average molecular weight comprising a thermoplastic silicon-containing polymer block B 200 500,000, said block A mainly formula

[0007]

Embedded image A thermosetting copolymer characterized by being a perhydropolysilazane block having a skeleton composed of repeating units represented by

[0008]

Embedded image And a perhydropolysilazane having a number average molecular weight of 100 to 50,000 and a polycarbosilane and polysilaz having a number average molecular weight of 100 to 50,000
Tylene, polycarbosilastyrene, methylpolysilane,
Phenyl polysilane, polytitanocarbosilane, polydi
Selected from luconocarbosilane and polydisiylazane
With a thermoplastic silicon-containing polymer to be provided. Further, in the above production method, perhydropolysilazane, polycarbosilane,
Lysylstyrene, polycarbosilastyrene, methylpoly
Silane, phenylpolysilane, polytitanocarbosila
, Polyzirconocarbosilane and polydisilylazane
With a thermoplastic silicon-containing polymer selected from
MX _n (wherein, M is at least one metal element selected from B, Al, Ti, Zr, Hf, X may be the same or different, and may be a hydrogen atom, a halogen atom, a hydroxyl group, a carbonyl group, Or an alkoxy group, a phenoxy group, an acetylacetoxy group, an alkyl group, an alkenyl group, a cycloalkyl group, an alkylamino group or an amino group having 1 to 20 carbon atoms, and n is a valence of the metal element M. ) At an atomic ratio of (Si) / M in all components of 500 or less, and a thermosetting copolymer obtained by the production method. Coalescence is also provided.

[0009] Perhydropolysilazane bonds to many thermoplastic silicon-containing polymers having Si-H bonds or N-H bonds only by heating, but a copolymer comprising a perhydropolysilazane block and a thermoplastic silicon-containing polymer block. The united structure may be a structure in which a perhydropolysilazane block and a thermoplastic silicon-containing polymer block are bonded to each other in a main chain, a structure in which side groups of these blocks react and crosslink, or a structure having both of them. it can. When functional groups are present in the thermoplastic silicon-containing polymer, the perhydropolysilazane reacts with many of the functional groups in the thermoplastic silicon-containing polymer to form bonds only by heating. When there is no functional group or when the reactivity is low, a bond can be easily formed by introducing a reactive group into the terminal or side chain of the thermoplastic silicon-containing polymer.

The perhydropolysilazane used in the present invention has the formula

[0011]

Embedded image Is a polysilazane in which the side chains are all hydrogen atoms, and is mainly chain-like, but can have a cyclic portion and further have a crosslinked structure. Examples of such perhydropolysilazane include a perhydrosilazane oligomer obtained by ammonolysis of a dichlorosilane-pyridine complex (Japanese Patent Publication No. 63-16325), and an inorganic high polymer obtained by heating this oligomer in a basic solution. (JP-A-1-1381
No. 08) and modified polysilazane obtained by reacting an oligomer with ammonia or the like (JP-A-1-138107). Perhydropolysilazane is S
Since it has i-H, NH bonds and has high reactivity, it is easy to copolymerize, and it is thermosetting, so it is most suitable for the purpose of the present invention. Further, in the copolymerization with the SiC precursor polymer, since C is not present in the repeating unit, there is an effect of suppressing the remaining of free carbon, which is the biggest defect of the SiC precursor polymer.

The number average molecular weight of the perhydropolysilazane is in the range of 100 to 50,000. If the molecular weight is smaller than this, a high molecular weight copolymer excellent in ceramic yield cannot be obtained. On the other hand, if it is larger than this, gelation occurs by polymerization. The thermoplastic silicon-containing polymer that can be used in the present invention is a silicon carbide-based polymer containing silicon in the main chain.
The precursor polymers are polycarbosilane , polysilastyrene, polycarbosilastyrene, methylpolysilane, phenylpolysilane , polytitanocarbosilane, polyzirconocarbosilane , and polydisilylazane. When these polymers have a group that reacts with perhydropolysilazane, a copolymer is formed by directly mixing and heating both polymers. Groups that react with perhydropolysilazane include amide groups, imide groups, hydrosilyl groups, hydroxyl groups, alkoxy groups, carboxyl groups, keto groups, halogen atoms, epoxy groups, and the like.

The molecular weight of the thermoplastic silicon-containing polymer is:
A number average molecular weight in the range of 100 to 50,000 is used. If the molecular weight is smaller than this, it evaporates during the reaction, and the polymer yield is low. If it is larger than this, the copolymer gels due to polymerization. As noted above, many thermoplastic silicon-containing polymers and perhydropolysilazanes form bonds upon direct heating. Usually, a solvent is used, but the solvent may be any as long as it does not react with the thermoplastic silicon-containing polymer and perhydropolysilazane, such as methylene chloride, chloroform, carbon tetrachloride, bromoform, ethylene chloride, ethylidene chloride, trichloroethane, tetrachloroethane, and the like. Halogenated hydrocarbons, ethyl ether, isopropyl ether, ethyl butyl ether, butyl ether, 1,
Ethers such as 2-dioxyethane, dioxane, dimethyldioxane, tetrahydrofuran, tetrahydropyran, pentane, hexane, isohexane, methylpentane, heptane, isoheptane, octane, isooctane, cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, benzene, toluene , Xylene, ethylbenzene and the like.
The reaction temperature is not limited, but is preferably in the range of 0 to 300 ° C. The reaction time may usually be 30 minutes or more.

In addition, whether the thermoplastic silicon-containing polymer has or does not have a group capable of reacting with perhydropolysilazane, a metal compound can be further added for crosslinking. Examples of the metal compound forming a cross-linking bond include, for example, halides, hydroxides, alkylated compounds, alkoxides such as B, Al, Ti, Zr, and Hf.
Acetylacetonate, metallocene and the like can be used. These metal compounds react with the hydrogen atoms bonded to the silicon or nitrogen atoms of the perhydropolysilazane, and also react with the side groups of the thermoplastic silicon-containing polymer, and mainly react with the silicon or nitrogen atoms of the perhydropolysilazane. A cross-link is formed by bonding atoms such as silicon constituting the main chain of the thermoplastic silicon-containing polymer via metal atoms. Alternatively, it reacts with a reactive site in the side chain group of the thermoplastic silicon-containing polymer to form a cross-link via the side chain. By introducing such a cross-linking, it is possible to obtain a copolymer sufficiently reflecting the thermosetting property of perhydropolysilazane.

The amount of the metal compound for forming the cross-linking is preferably such that the ratio of the number of metal atoms to the total number of silicon atoms in the starting polymer is 500 or less. Thus, according to the present invention, a metal compound is added to a thermoplastic silicon-containing polymer and perhydropolysilazane and mixed together with a thermosetting copolymer obtained by directly bonding a thermoplastic silicon-containing polymer and perhydropolysilazane. A thermosetting copolymer obtained by the reaction is also provided. The molecular weight of the copolymer obtained generally ranges from 200 to 500,000. If the molecular weight is too large, a gel is formed, and the solubility in a solvent is significantly deteriorated.

The ratio of the perhydropolysilazane block to the thermoplastic silicon-containing polymer block in the obtained polymer is not particularly limited as long as the polymer becomes thermosetting as a result, but is generally included in each block. The ratio of silicon atoms is 0.5 or more, preferably the ratio is 1 or more. When this ratio is large, the thermosetting perhydropolysilazane block inhibits the softening of the thermoplastic block, and as a result, a thermosetting copolymer is obtained.

The thermosetting copolymer thus obtained is soluble in an organic solvent, and a shaped ceramic can be easily obtained. Further, free C in ceramics can be suppressed by changing the composition of the polymer. Impurities mixed in the infusibilization step can be suppressed. Si obtained from silicon carbide precursor polymer
Compared with C 2, SiC derived from a thermosetting polysilazane-based copolymer has N introduced therein, and thus retains an amorphous to microcrystalline structure up to high temperatures. Therefore, the high-temperature strength of the structural material obtained from the thermosetting copolymer can be improved.

In addition, there are various forms of producing a ceramic product using the thermosetting copolymer as a ceramic precursor, such as a method of directly shaping and firing, a method of impregnating a preform, and a method of using as a binder. In these cases, in order to convert the thermosetting copolymer into a ceramic, the solid polymer is dissolved in a solvent,
After removing the solvent until it has the required viscosity, it is shaped into fibers and membranes, impregnated into preforms, and mixed with ceramic powder. After removing the solvent as needed, thermal decomposition is performed.

The liquid polymer is shaped into a fiber or a film, impregnated into a preform, mixed with a ceramic powder, and then cured by heating. Then, pyrolysis is performed. The thermal decomposition is performed in an atmosphere of He, Ar, N ₂ , or H ₂ , a mixed atmosphere thereof, or a pressurized atmosphere or a reduced-pressure atmosphere. The temperature is preferably from 600C to 1700C.

[0020]

The block copolymerization of perhydropolysilazane with a thermoplastic silicon-containing polymer, such as a silicon carbide precursor polymer, makes the polymer thermosetting and eliminates the need for an infusibilizing step in the ceramicization step. The process is simplified, and there is no risk of impurities being mixed into the obtained ceramic. In particular, by performing block copolymerization of a silicon carbide precursor polymer and perhydropolysilazane, a ceramic that combines the excellent characteristics of both silicon carbide and silicon nitride can be obtained by a simple method without an infusibilization step as described above. Can be manufactured.

[0021]

【Example】

Reference Example 1 A four-necked flask having an inner volume of 1 liter was equipped with a gas blow-in tube, a mechanical stirrer, and a dewar condenser. After replacing the inside of the reactor with deoxygenated dry nitrogen, 490 ml of degassed dry pyridine was placed in a four-necked flask, and the mixture was cooled with ice. Next, when 51.6 g of dichlorosilane was added, a white solid adduct (SiH ₂ Cl ₂ .2C ₅ H ₅ N) was formed. The reaction mixture was ice-cooled, and while stirring, 51.0 g of purified ammonia was blown through a sodium hydroxide tube and an activated carbon tube.

After completion of the reaction, the reaction mixture was centrifuged, washed with dry pyridine, and then filtered under a nitrogen atmosphere to obtain 850 ml of a filtrate. The solvent was distilled off from 5 ml of the filtrate under reduced pressure to obtain 0.102 g of resin solid perhydropolysilazane. The number average molecular weight of the obtained polymer was 980 as measured by GPC. When the IR (infrared absorption) spectrum (solvent: dry o-xylene; concentration of perhydropolysilazane: 10.2 g / l) of this polymer is examined, the wave number (cm ^-1 ) is 3350 (apparent absorption coefficient ε = 0) .
Absorption based on NH at 557 lg ^-1 cm ^-1 ) and 1175; 2170 (ε
= 3.14) Absorption based on SiH; SiH and S from 1020 to 820
It was confirmed to show absorption based on iNSi. The ¹ H NMR (proton nuclear magnetic resonance) spectrum (60 MHz
z, the solvent CDCl ₃ / reference substance TMS) was examined, and it was confirmed that all showed broad absorption. That is, δ4.8
And 4.4 (br, SiH); 1.5 (br, NH) absorptions were confirmed.

Reference Example 2 Pyridine of perhydropolysilazane obtained in Reference Example 1
Solution (concentration of perhydropolysilazane, 5.04% by weight) 100
ml into a 300 ml pressure-resistant reaction vessel,
Add 2.8 g (0.165 mol) of ammonia, and add 3 g at 60 ° C in a closed system.
The reaction was performed with stirring for hours. During this time a large amount of gas
Occurred. The pressure before and after the reaction is 1.2kg / cm ^TwoRose. Room
After cooling to a temperature, 200 ml of dry o-xylene was added, and the pressure was
After removing the solvent at 5 mmHg and a temperature of 50 to 70 ° C., 5.22 g of
A white powder was obtained. This powder is made of toluene,
Compatible with drofuran, chloroform and other organic solvents
It was soluble.

The number average molecular weight of the polymer powder was 1,740 as measured by GPC. As a result of analyzing the IR spectrum (solvent: o-xylene), the wave number (cm
^-1 ) absorptions based on NH of 3350 and 1175; absorptions based on SiH of 2170; absorptions based on SiH and SiNSi of 1020 to 820. Further, the polymer powder
Analysis of the ¹ H NMR spectrum (CDCl ₃ , TMS) shows that all of them show a broad absorption. That is, δ4.8 (br, SiH
₂ ), δ 4.4 (br, SiH ₃ ) and δ 1.5 (br, NH) were observed. (SiH ₂ ) / (SiH ₃ ) = 4.1.

Reference Example 3 The pyridine solution of perhydropolysilazane obtained in Reference Example 1 (concentration of perhydropolysilazane, 5.24% by weight) 10
0 ml was placed in a pressure-resistant reaction vessel having an internal volume of 300 ml, and the reaction was carried out while stirring at 100 ° C. for 3 hours in a closed system under a nitrogen atmosphere. During this time, a large amount of gas was generated. The pressure before and after the reaction is 1.
It increased by 0 kg / cm ² . After cooling to room temperature, 200 ml of dry ethylbenzene was added, and the solvent was removed at a pressure of 3 to 5 mmHg and a temperature of 50 to 70 ° C. to obtain 4.68 g of a white powder. This powder was soluble in toluene, tetrahydrofuran, chloroform and other organic solvents.

The number average molecular weight of the polymer powder was measured by GPC and found to be 2070. In addition, as a result of analysis of its IR spectrum (solvent: ethylbenzene), absorption based on NH at wave numbers (cm ⁻¹ ) of 3350 and 1175;
Absorption based on iH; It was confirmed to exhibit absorption based on SiH and SiNSi of 1020 to 820. Further, when the ¹ H NMR spectrum (CDCl ₃ , TMS) of the polymer powder was analyzed,
All show broad absorption. That is, δ4.8 (br,
SiH ₂ ), δ 4.4 (br, SiH ₃ ) and δ 1.5 (br, NH) were observed. (SiH ₂ ) / (SiH ₃ ) = 4.1.

Example 1 A solution of polycarbosilane (Shin-Etsu Chemical) in φ-xylene 50
ml (2.43 g of polycarbosilane) in titanium n-butoxide
0.65 g was added, and the mixture was heated and refluxed in N ₂ for 1 hour. After cooling to room temperature, φ of the perhydropolysilazane obtained in Reference Example 2 was
-40 ml of xylene solution (1.94 g of perhydropolysilazane)
Was added and heated at 100 ° C. for 1 hour in N ₂ . After cooling to room temperature, the solvent was removed at a pressure of 3 to 7 mmHg and a temperature of 50 to 70 ° C. to obtain 4.82 g of a black-blue powder. This powder was soluble in toluene, tetrahydrofuran, chloroform and other organic solvents.

The number average molecular weight of the polymer powder was 2,540 as measured by GPC. As a result of the IR spectrum analysis, the N of the wave numbers (cm ^-1 ) 3350 and 1170
H-based absorption; 2170 and 2120 based on SiH absorption; 10
20-820 absorption based on SiH and SiNSi; 1250 SiCH ₃
Based on: 1100 SiO based absorption: 2950, 2900,
It was confirmed to exhibit absorption based on CH of 2880, 1470 to 1360. Further, ¹ HNMR spectrum of the polymer powder (CDC
l ₃ , TMS), all show broad absorption. That is, δ4.8 (br, SiH ₂ ), δ4.3 (br, SiH
H ₃ ), δ 0.2 (br, SiCH ₃ ), δ 1.4 and δ 0.9 (br, C
H) and δ 3.7 (br, -C-CH ₂ O) were observed.

When the polymer powder was thermally decomposed in N ₂ at 1000 ° C., a black solid was obtained in a yield of 65% by weight.
No melting was observed during pyrolysis. Comparative Example 1 Poly-carbosilane (Shin-Etsu Chemical Co., Ltd.) solution of φ-xylene 50
To cc (2.43 g of polycarbosilane), 40 cc (1.94 g of perhydropolysilazane) of the perhydropolysilazane obtained in Reference Example 2 was added, and the mixture was heated and refluxed in N ₂ for 3 hours. After cooling to room temperature, pressure 3-7mmHg, temperature 50-70
After removing the solvent at ℃, 4.01 g of pale yellow powder was obtained. This powder was pyrolyzed at 1000 ° C. in N ₂ , and melted during the pyrolysis to obtain a black porous mass.

Example 2 200 ml of anhydrous benzene, 20 g of metallic sodium and 7 g of metallic potassium were added to a 1 liter four-necked flask and kept at 70 ° C.
25 g of methyldichlorosilane, 30 g of dimethyldichlorosilane and 50 g of trimethylchlorosilane were added dropwise thereto and reacted for 24 hours to obtain a pale yellow polysilane having a number average molecular weight of 400 and having a Si—H bond. 2.0 g of this polysilane and 0.5 of zirconium isopropoxide are placed in a 300 ml four-necked flask.
g and 40 ml of φ-xylene were added, and the mixture was heated and refluxed in N ₂ for 3 hours. After cooling to room temperature, 100 ml (5.4 g of perhydropolysilazane) of perhydropolysilazane obtained in Reference Example 3 was added, and the mixture was heated at 120 ° C. for 1 hour in N ₂ . After cooling to room temperature, pressure 3-7mmHg, temperature 50-70 ℃
After removing the solvent with, 7.22 g of a pale yellow powder was obtained. This powder was soluble in toluene, tetrahydrofuran, chloroform and other organic solvents.

The number average molecular weight of the polymer powder was 2,480 as measured by GPC. As a result of the IR spectrum analysis, the N of the wave numbers (cm ^-1 ) 3350 and 1170
H-based absorption; 2170 SiH-based absorption; 1020-820
Absorption based on SiH and SiNSi of 1250; Absorption based on SiCH ₃ of 1250: Absorption based on SiO of 1100: 2950, 2900, 2880,147
It was confirmed to exhibit absorption based on CH from 0 to 1360.
Additionally, ¹ HNMR spectrum of the polymer powder (CDCl _3, TMS)
, All show broad absorption.
That is, δ4.8 (br, SiH ₂ ), δ4.4 (br, SiH ₃ ), δ0.2
(br, SiCH ₃ ), δ 1.4 and δ 0.9 (br, CH), δ 3.5 (br,
-C-CHO) was observed.

When the polymer powder was thermally decomposed in N ₂ at 1000 ° C., a black solid was obtained in a yield of 82% by weight. No melting was observed during pyrolysis. Example 3 Polysilastyrene (manufactured by Nippon Soda) φ-xylene solution 40
ml (1.84 g of polysilastyrene) and 40 ml of a φ-xylene solution of perhydropolysilazane obtained in Reference Example 1 (1.85 g of perhydropolysilazane) were placed in a 300 ml four-necked flask and cooled to 0 ° C. 0.03 g of boron trichloride was gradually added thereto. After the addition, the solution was heated to 60 ° C and held for 1 hour. After cooling to room temperature and removing the solvent, 3.35 g of a pale yellow powder was obtained. When this powder was pyrolyzed at 1000 ° C. in N ₂ , a black solid was obtained with a yield of 78 wt%. No melting was observed during pyrolysis.

Example 4 A 500-ml four-necked flask was equipped with a mechanical stirrer, a gas inlet tube, a cooling tube, and a dropping funnel. 50g here
Disilane mixture (tetrachlorodimethyldisilane 50wt
%, Trichlorotrimethyldisilane 50 wt%)
While maintaining the N ₂ atmosphere, 120 g of hexamethyldisilazane was added to disilane from a dropping funnel. The mixture is placed under N ₂
Heated to 220 ° C. while removing by-products. 3 to 220 ° C
After holding for a time, the mixture was cooled to room temperature to obtain a cloudy glassy polymer. 300 ml of dry toluene was added thereto to dissolve the polymer, and this solution was filtered through a 1.0 μm membrane filter. Excluding the solvent of the filtrate, 22.5 g of a pale yellow resinous solid was obtained. The softening point of this resin is about 80
° C.

1.5 g of the above polymer was dissolved in 30 ml of φ-xylene and introduced into a 300 ml four-necked flask. To this was added 100 ml of a φ-xylene solution of perhydropolysilazane obtained in Reference Example 2 (4.30 g of perhydropolysilazane), and the mixture was ice-cooled. 0.15 g of triethylaluminum was added thereto, gradually heated to 80 ° C., and kept for 1 hour. After cooling to room temperature and removing the solvent, 5.45 g of a pale yellow powder was obtained.
When this powder is thermally decomposed at 1000 ° C. in N ₂ , a black solid is produced.
Obtained in wt% yield. No melting was observed during pyrolysis.

[0035]

According to the present invention, a thermosetting copolymer obtained by block copolymerizing a perhydropolysilazane with a thermoplastic silicon-containing polymer such as a silicon carbide precursor polymer can be obtained. Especially in ceramics obtained by copolymerization with SiC precursor polymer, N
The crystallization of SiC can be suppressed, and the infusibilization step is not required, so that impurities (especially O) are not introduced, heat resistance is improved, and free C can be suppressed as compared with ceramics derived from SiC precursor. Therefore, there is an effect that the high temperature oxidation resistance is also excellent.

Continued on the front page (72) Inventor Yuji Tashiro 1-3-1, Nishitsurugaoka, Oimachi, Iruma-gun, Saitama Prefecture Tonen Co., Ltd. (72) Inventor Takeshi Isota 1-chome, Nishitsurugaoka, Oimachi, Iruma-gun, Saitama No. 3 No. 1 Tonen Co., Ltd. Research Laboratory (56) References JP-A-2-175726 (JP, A) JP-A-62-195024 (JP, A) JP-A-63-186736 (JP, A) 60-141758 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 81/00 C01B 21/068 C04B 35/584 CA (STN) REGISTRY (STN)

Claims (6)

(57) [Claims] 1. A perhydropolysilazane block A having a number average molecular weight of 100 to 50,000 and a number average molecular weight of 100 to 50,0
00 polycarbosilane, polysilastyrene, polycarbo
Sila styrene, methyl polysilane, phenyl polysila
, Polytitanocarbosilane, polyzirconocarbosila
And a thermoplastic silicon-containing polymer block B selected from polystyrene and polydisilylazane having a number average molecular weight of 2
A block copolymer of from 00 to 500,000, wherein said block A is mainly of the formula A thermosetting copolymer, which is a perhydrosilazane block having a skeleton composed of a repeating unit represented by the following formula: 2. The thermosetting copolymer according to claim 1, wherein the atomic ratio of Si contained in the block A to Si contained in the block B is 1 or more. 3. The formula: And a perhydropolysilazane having a number average molecular weight of 100 to 50,000 and a polycarbosilane and polysilaz having a number average molecular weight of 100 to 50,000
Tylene, polycarbosilastyrene, methylpolysilane,
Phenyl polysilane, polytitanocarbosilane, polydi
Selected from luconocarbosilane and polydisiylazane
A method for producing a thermosetting copolymer, characterized by reacting a thermoplastic silicon-containing polymer to be used. 4. The formula: And a perhydropolysilazane having a number average molecular weight of 100 to 50,000 and a polycarbosilane and polysilaz having a number average molecular weight of 100 to 50,000
Tylene, polycarbosilastyrene, methylpolysilane,
Phenyl polysilane, polytitanocarbosilane, polydi
Selected from luconocarbosilane and polydisiylazane
And a thermoplastic silicon-containing polymer of the formula MX _n (wherein M
Is at least one metal element selected from B, Al, Ti, Zr, and Hf; X may be the same or different; and is a hydrogen atom, a halogen atom, a hydroxyl group, a carbonyl group, or a group having 1 to 1 carbon atoms. 20, alkoxy group, phenoxy group, acetylacetoxy group, alkyl group, alkenyl group, cycloalkyl group, alkylamino group or amino group,
n is the valence number of the metal element M. ) At an atomic ratio of (Si) / M in all components of 500 or less. 5. S contained in perhydropolysilazane
5. The method for producing a thermosetting copolymer according to claim 3, wherein the atomic ratio of i to Si contained in the thermoplastic silicon-containing polymer is 1 or more. 6. A thermosetting copolymer produced by the method according to claim 4.