JPH04164923A - Polyphosphosilazane, its production, and phosphorated ceramic - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel polyphosphosilazane, a method for producing the same, and phosphorus-containing ceramics.

[Prior art and its problems]

Regarding polysilazane, perhydrosilazane, polyorgano(hydro)silazane, polymetallosilazane (containing metals such as Ti, AQ, Zr, B, etc.) have been reported, but there are no reports on polyphosphosilazane. .

The present inventors have discovered that polyphosphosilazane can be obtained by reacting polysilazane with a phosphorus compound, and this polyphosphosilazane has excellent adhesiveness to various substrates, and can be used for dip coating, spray coating, etc. A thin film can be easily produced using a simple coating method, and when this thin film is heat-treated,
It has been found that a transparent ceramic thin film with a higher refractive index can be obtained compared to ceramic thin films obtained from conventional polysilazane.

[Problem of invention]

Accordingly, one object of the present invention is to provide a new polysilazane, a method for producing the same, and a phosphorus-containing ceramic that exhibits excellent adhesion to various substrates and provides a transparent ceramic thin film with a high refractive index upon heat treatment.

[Means for solving the invention]

According to the present invention, in polysilazane, the following general formula (
Provided is a polyphosphosilazane having at least one of the crosslinking bonds represented by i) to (iv), having a phosphorus/silicon atomic ratio within the range of 0.01 to 5, and having a number average molecular weight of about 200 to 500,000. be done.

(In the formula, R6 is a hydrogen atom, a halogen atom, a carbon atom number of 1
-20 alkyl groups, alkenyl groups.

(a cycloalkyl group, an aryl group, an alkoxy group, an alkylamino group, a hydroxyl group, or an amino group, and R7 is a residue bonded to the nitrogen atom of a group having a nitrogen atom among R6). For example, a molecule having at least a SiH bond or a SiNH bond and a number average molecular weight of about 100-s
o, ooo polysilazane and the following general formula (1)-
A phosphorus compound represented by (V) is reacted to obtain a polyphosphosilazane having a phosphorus/silicon atomic ratio in the range of 0.01 to 5 and a number average molecular weight of 200 to 500,000. A method for producing a polyphosphosilazane is provided.

(1)P(R4)3 (■) ((R4)2PN)n (III) P(R4).

(IV) R20°(V)OP(R4)3 (In these formulas, R4 may be the same or different,
A hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an alkoxy group, an alkylamino group, a hydroxyl group, or an amino group having 1 to 20 carbon atoms, and n is an integer of 2 or more. ) Furthermore, according to the present invention, there is provided a ceramic containing at least silicon, nitrogen and phosphorus and having a phosphorus/silicon atomic ratio in the range of 0.01 to 5, the ceramic having the formula S
A phosphorus-containing ceramic is provided which is characterized by having a bond represented by i-0-P, Si-P or PN.

The polysilazane used as a raw material in the present invention has at least a SiH bond or a SiNH bond in the molecule and has a number average molecular weight in the range of about 100 to so, ooo. Such polysilazane includes perhydropolysilazane, polyorgano(hydro)polysilazane, and polymetallosilazane.As the phosphorus compound to be reacted with the 6-polysilazane, those represented by the general formulas (1) to (V) are used. It will be done. Specific examples include alkylphosphines and arylphosphines (e.g., trimethylphosphine, triethylphosphine, tripropylphosphine, tributylphosphine, triphenylphosphine, etc.); phosphites (e.g., trimethylphosphine, triethylphosphine, triphenylphosphine, etc.); phosphite, tributyl phosphite, etc.); phosphate esters (e.g., trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, etc.); amidophosphines (e.g., hexamethylphosphorustriamide, hexamethylphosphoric triamide); etc.); phosphazenes (e.g., phosphonitric chloride trimer); halogenated phosphines (e.g., phosphorus trichloride, phosphorus pentachloride, etc.); and phosphoric acid.

That is, the polyphosphosilazane of the present invention has the first characteristic in the polysilazane used as its raw material.

The reaction between polysilazane and a phosphorus compound and the structure of the compound obtained by the reaction depend on the type of the phosphorus compound.

For example, p represented by general formula (1) as a phosphorus compound
When (R')3 is used, the resulting polyphosphosilazane has hydrogen atoms bonded to at least some silicon atoms and/or hydrogen atoms bonded to nitrogen atoms in the main skeleton of the polysilazane, and p(R4)3. reacts, and the silicon atom and/or nitrogen atom becomes P(R4).

It is a compound characterized by having a side chain group condensed with or having a cyclic or crosslinked structure.

Next, the reaction between polysilazane and a phosphorus compound will be described in detail.

In the reaction between the Si-H bond of polysilazane and a substance having an alkoxy group among p(R')3, a phosphorus compound P(OR')J'3-m(RsHuff)Li
Kill group, m=1.2.3) (7) Flukoxy (OR”
) extracts the hydrogen atom of the Si-H bond to form R'H and is eliminated, thereby forming a Si-0-P bond.

On the other hand, polJ:, z5zan (7) N-HM combination and p (
oR') In the reaction with mP3-1m, P(OR4)
The hydrogen atom of the N-H bond is extracted by J'z-m, and an N-P bond is formed as shown below.

Since P(ORs)IIIR',-1 can be up to trifunctional, depending on the type of starting P(OR4)mR'a-+a or the reaction conditions, the polyphosphosilazane formed can have between 1 and 1 with respect to phosphorus. It can be a trifunctional polymer.

The monofunctional polymer has the following structure in which a pendant group is introduced into Si and/or N of the main chain of polysilazane.

In di- or tri-functional polymers, a cyclic, crosslinked structure is formed in the polysilazane skeleton via Pg atoms. The cyclic structure is P(OR
4), -1R', - includes a structure in which two functional groups in the molecule are condensed with adjacent silicon atoms and nitrogen atoms of polysilazane. A crosslinked structure is generated when two or more functional groups of P(OR4)m-4R4°-1 are condensed with two or more molecules of polysilazane.

"Also, some trifunctional polymers have the above-mentioned cyclic structure and crosslinked structure at the same time. Usually, polysilazane P (
OR4), by reaction with R'3-+m, formulas (3) to (
The polymer shown in 8) is obtained.

As described above, the structural change from polysilazane to polyphosphosilazane is that a new pendant group or cyclic or crosslinked structure is formed based on the polysilazane skeleton.

In the reaction between the Si-1 bond of polysilazane and a substance having a halogen atom in p
The halogen atom in 1.2.3) withdraws the hydrogen atom from the Si-H bond to form HX and is eliminated, thereby forming a Si
-P bond is formed.

On the other hand, in the reaction between the ~H bond of polysilazane and a phosphorus compound having a halogen atom, the hydrogen atom of the N-H bond is extracted and an N-P bond is formed as described below.

Since the phosphorus compound PXll(R4)-+w can be up to trifunctional depending on the number of halogen atoms, the resulting polyphosphosilazane can be a mono- to trifunctional polymer with respect to phosphorus. The monofunctional polymer has the following structure in which a pendant group is introduced into Si and/or N of the main chain of polysilazane.

In the 2-3 functional polymer, a cyclic, crosslinked structure is formed in the polysilazane skeleton via P atoms. The cyclic structure includes a structure in which two functional groups in one molecule of the phosphorus compound are condensed with adjacent silicon atoms and nitrogen atoms of polysilazane. A crosslinked structure occurs when two or more functional groups of a phosphorus compound are condensed with two or more molecules of polysilazane.

Moreover, some trifunctional polymers have the above-mentioned cyclic structure and crosslinked structure at the same time.

Si-H bond of polysilazane and phosphorus compound P(I(4)
In the reaction with a substance having a hydrogen atom, the hydrogen atom of the phosphorus compound PH1l(R'')3-rm extracts the hydrogen atom of the Si-H bond to generate H2 and is eliminated.

A Si-P bond is formed.

On the other hand, in the reaction between the N-H bond of polysilazane and a phosphorus compound having a hydrogen atom element, the hydrogen atom of the N-H bond is extracted and an N-P bond is formed as described below.

Since the phosphorus compound PI(m(R4)3-* can be up to trifunctional depending on the number of hydrogen atoms, the phosphorus compound p
Polyphosphosilazane having a structure similar to that described for x, , (R4)i-ea can be produced.

Si-H bond of polysilazane and phosphorus compound P(R4),
Among these, in the reaction with a substance having an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, or an alkylamino group, the organic group of the phosphorus compound p(R4)3 withdraws the hydrogen atom of the Si-H bond to form R. By generating 'H and eliminating it, a Si-P bond is formed.

However, when one of the alkylamino groups bonded to the nitrogen atom is a hydrogen atom, a dehydrogenation reaction occurs and a Si-N-P bond is formed by the reaction described below.

On the other hand, in the reaction between the N-H bond of polysilazane and a phosphorus compound having an alkyl group, alkenyl group, cycloalkyl group, aryl group, or alkylamino group, the hydrogen atom of the N-H bond is extracted and the following reaction occurs. An N-P bond is formed.

Since the phosphorus compound P(R4)3 can be up to trifunctional, depending on the type of starting phosphorus compound or the reaction conditions, the resulting polyphosphosilazane may be the phosphorus compound PXm(R4)a-wr or PI. (ml(R4)3-11
It has the same structure as when using .

Si-H bond of polysilazane and phosphorus compound P(R4)2
Among these, in the reaction with substances having amino groups and hydroxyl groups,
The hydrogen atom in Z of the phosphorus compound PZII (R4) 3-* (Z is an amino group or a hydroxyl group) extracts the hydrogen atom of the Si-H bond to generate H2 and desorb, thereby forming Si-
An N-P bond or a Si-0-P bond is formed.

On the other hand, in the reaction between the N-H bond of polysilazane and a phosphorus compound having an amino group or a hydroxyl group, the hydrogen atom of the N-H bond is extracted, resulting in an N-P bond or N-
A 0-P bond is formed.

Since the phosphorus compound PZm(R4)a-tm can be up to trifunctional depending on the number of amino groups and hydroxyl groups, the resulting polyphosphosilazane can be a mono- to trifunctional polymer with respect to phosphorus. . The monofunctional polymer has the following structure in which a pendant group is introduced into Si and/or N of the main chain of polysilazane.

In a di- or tri-functional polymer, a cyclic, crosslinked structure is formed in the polysilazane skeleton via a P atom. The cyclic structure includes a structure in which two functional groups in one molecule of the phosphorus compound are condensed with adjacent silicon atoms and nitrogen atoms of polysilazane. A crosslinked structure occurs when two or more functional groups of a phosphorus compound are condensed with two or more molecules of polysilazane.

^・ ■ “Also, some trifunctional polymers have the above-mentioned cyclic structure and crosslinked structure at the same time.

Next, polysilazane and phosphazene ((R2'PN)n
), the reaction with n=3 substances is shown below.

In the reaction between the Si-)1 bond of polysilazane and (R24PN), the R4 group of (R'□PN) pulls out the hydrogen atom of the -SiH bond, producing R4H and eliminating it, thereby forming the Si-P bond. It is formed.

On the other hand, in the reaction between the N)I bond of polysilazane and (R'□PN)3, the hydrogen atom of the NH bond is extracted by R4 of (R'2PN), and a new N-P bond is formed.

Since (R4□PN)3 can be up to hexafunctional, depending on the type of starting (R'□PN) or the reaction conditions, the resulting polyphosphosilazane has a mono- to trifunctionality with respect to the phosphazene molecule. It can be a polymer.

(2) The functional polymer has the following structure in which a pendant group is introduced into Si and/or N of the main chain of polysilazane.

In the 2- to 6-functional polymer, a cyclic, crosslinked structure is formed in the polysilazane skeleton via phosphazene molecules.

The cyclic structure includes a structure in which two or more functional groups in one molecule of phosphazene are condensed with a silicon atom and/or a nitrogen atom of the same polysilazane molecule. A crosslinked structure occurs when two or more functional groups of phosphazene are condensed with two or more molecules of polysilazane.

Moreover, some trifunctional or higher functional polymers have the above-mentioned cyclic structure and crosslinked structure at the same time.

The polysilazane used in the present invention has at least S in its molecule.
Although it is a polysilazane having an i-H bond or a Si-N-H bond, not only polysilazane alone but also a copolymer of polysilazane and other polymers or a mixture of polysilazane and other compounds can be used.

The polysilazane used in the present invention includes those having a chain, cyclic, or crosslinked structure, or those having a plurality of these structures simultaneously in the molecule, and these can be used alone or as a mixture.

Examples of the polysilazane preferably used in the present invention include polysilazane having a main skeleton composed of units represented by the following general formula (VI) and having a number average molecular weight of about 100 to 50,000.

(In the formula, R1, R'', R3 are hydrogen atoms, alkyl groups,
It represents an alkenyl group, a cycloalkyl group, an aryl group, or a group other than these groups in which the group directly bonded to silicon is carbon, an alkylsilyl group, an alkylamino group, or an alkoxy group. However, at least one of R', R2, and R3 is a hydrogen atom. ) - For boat fishing, R1, R2 and R3 of the general formula (VI)
is hydrogen, an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, a cycloalkyl group having 5 to 7 carbon atoms, an aryl group, an alkylsilyl group having 1 to 4 carbon atoms. group, an alkylamino group having 1 to 5 carbon atoms,
Those selected from the group consisting of alkoxy groups having 1 to 5 carbon atoms are preferred because of their low steric hindrance, and more preferred are hydrogen atoms, methyl groups, ethyl groups, vinyl groups, allyl groups, and methylamino groups.

selected from ethylamino, methoxy and ethoxy groups.

The compound having hydrogen atoms in R1, t+2 and R3 in the general formula (VI) is perhydropolysilazane, and its production method is disclosed, for example, in JP-A-60-145903, D, 5e.
Communication of A
m,Cer,Soc,,C-13,January19
It was reported in 83. What is obtained by these methods is a mixture of polymers having various structures, but basically contains a chain part and a cyclic part in the molecule (1+SiH2NH+SiH2N5-+SiH3).

It can be represented by the chemical formula (a+b+c=1). An example of the structure of perhydropolysilazane is shown below.

The method for producing polysilazane having hydrogen atoms in R1 and R2 and a methyl group in R3 in general formula (VI) includes D, 5erfe
rth et Polym, Prepr, Arm, Che
tx, Soc, , Div, Polym, Chem,
.

25.10 (1984). The polysilazane obtained by this method has a repeating unit of 1+Si.
H.

NCH, +- chain polymer and cyclic polymer, neither of which has a crosslinked structure.

A method for producing polyorgano(hydro)silazane having a hydrogen atom in R1 and R3 and an organic group in R2 in the general formula (VI) is described by D., 5eyferth et al. Polym, Prepr.
,Am,Chen+,Soc,,Div,Polym,
chem, 25.10 (1984), JP-A-61-8
It is reported in Publication No. 9230. The polysilazane obtained by these methods mainly has a cyclic structure with a degree of polymerization of 3 to 5 with -+R2SiHNH+- as a repeating unit, or (R"SiHN1()x((R"SiH)1.5N)1
It has both a chain structure and a cyclic structure within the molecule represented by the chemical formula -x (0,4<x<1).

Polysilazane having a hydrogen atom at 81 and an organic group at R2 and R3 in the general formula (VI), and an organic group at R1 and R2,
Those with a hydrogen atom in R3 are 1+R1R”SiNR3
) as a repeating unit and mainly has a cyclic structure with a degree of polymerization of 3 to 5.

Next, among the polysilazane used in the present invention, general formula (VI)
Here are some representative examples of other things.

Among the polyorgano(hydro)silazane, D, 5ey
Communication of Am
,Cer,Soc,,C-132,July 1984
．． Some have a cross-linked structure within the molecule, as reported by. - Examples are as follows.

In addition, polysilazane (R1S
i(NH)X), or R1SiX3 and R" □S
Polysilazane having the following structure obtained by iX2(7) co-ammonia decomposition can also be used as a starting material in the present invention.

In the polysilazane used in the present invention, general formula (VI)
When the main chain skeleton is composed of units represented by the formula (1), the unit represented by the general formula (1) may be cyclized as shown above, and in that case, the cyclic portion becomes the terminal group, When not cyclized in this way, the terminal of the main chain skeleton can be a group similar to R1°R2,R' or hydrogen.

In addition to polysilazane that is soluble in organic solvents as described above, polysilazane that is insoluble in organic solvents, such as those shown in the figure below, can also be used as raw materials, but the reaction products of these with phosphorus compounds are also insoluble in organic solvents Therefore, it is subject to limitations in terms of application.

[Si(NH)2)nM, B111y, Bull,
Soc, Chem, Fr, 183 (1962)
[Si, N3H)nM, B111y, Bull, S
oc, Chem, Fr, , 1550 (1961
)■ (si2(N)l, ))□ C3x3(NH4
)).

M, B111y, Compt, Rend, , 250
, 4163 (1960); 251, 1639 (
1960) The polysilazane used in the present invention has a molecular weight of about 100 to
It has a number average molecular weight of 50,000 and is composed of cyclic polysilazane, linear polysilazane, or a mixture thereof. The raw material polysilazane preferably used in the present invention has a number average molecular weight of 250 to 20,000.
, more preferably about 500 to 10,000. If the molecular weight is too small, the reaction product with the phosphorus compound will also have a low molecular weight, and the property will be a viscous liquid, which will not only limit the application, but also cause a large amount of scattering during the firing process, resulting in a low ceramic yield. Undesirable. If the molecular weight is too large, the reaction product with the phosphorus compound tends to be insoluble in the solvent or becomes a gel, which is not preferable.

The phosphorus compound used in the present invention has the general formula (1) to
(V).

The number average molecular weight of the novel polyphosphosilazane of the present invention is 20
It is in the range of 0 to 500,000, preferably 800 to 200,000.

In order to produce the polyphosphosilazane of the present invention, a polysilazane having a number average molecular weight of about 100 to 50,000 and the general formula (
1) A phosphorus compound represented by (If), (nl), (IV) or (V) is reacted.

There are no particular restrictions on the polysilazane used in the present invention, and any available one can be used.However, in terms of reactivity with phosphorus compounds, in the polysilazane represented by the general formula (Vl), R'', R2, and R3 are Groups with low steric hindrance are preferred. That is, R1, R'' and R3 are preferably a hydrogen atom and an alkyl group of C□-2, and more preferably a hydrogen atom and an alkyl group of C□-2.

The phosphorus compound used in the present invention is not particularly limited, but from the viewpoint of reactivity, R4 in formula (1)-(V) is preferably a hydrogen atom, a halogen atom, and an alkyl group or alkoxy group having C□ to 2°. , hydrogen atoms and halogen atoms, and Cney □. More preferred are alkyl groups and alkoxy groups, and most preferred are hydrogen atoms, halogen atoms, and C1-4 alkyl groups and alkoxy groups. -For boat fishing, the formula (1
) to (V), R4 is selected from a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and an aryl group having 1 to 10 carbon atoms. are preferable, and methyl group, ethyl group, n-propyl group, j-propyl group, n-butyl group, i-butyl group, t-butyl group, phenyl group, benzyl group, tolyl group,
It is more preferably selected from methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, j-butoxy group, t-butoxy group, and phenoxy group.

The mixing ratio of polysilazane and phosphorus compound is preferably 0 so that the P/Si atomic ratio is from 0.001 to 100.
．． 01 to 60, more preferably 0.0
It is specified to be between 2 and 1.5. If the mixing ratio of the phosphorus compound is increased more than this, the phosphorus compound will simply be recovered unreacted without increasing the reactivity with the polysilazane, and if it is less than this, significant increase in molecular weight will not occur.

The reaction can be carried out without a solvent, but it is more difficult to control the reaction than when using an organic solvent, and a gel-like substance may be produced, so it is generally better to use an organic solvent. As the solvent, hydrocarbon solvents such as aromatic hydrocarbons, aliphatic hydrocarbons, and alicyclic hydrocarbons; halogenated hydrocarbons; aliphatic ethers; and alicyclic ethers can be used. Preferred solvents are methylene chloride, chloroform, carbon tetrachloride,
Bromoform, ethylene chloride, ethyldene chloride, trichloroethane, ethyl ether, isopropyl ether,
Ethers such as ethyl butyl ether, butyl ether, 1,2-dioxyethane, dioxane, dimethyldioxane, tetrahydrofuran, tetrahydropyran,
Pentane, hexane, methylpentane, heptane, isohbutane, octane, isooctane, cyclopentane,
These include hydrocarbons such as methylcyclopentane, cyclohexane, methylcyclohexane, benzene, toluene, xylene, and ethylbenzene.

In order to obtain a high molecular weight polyphosphosilazane, it is preferable to react the polysilazane and the phosphorus compound under basic conditions. In this case, basic conditions mean that a basic compound such as tertiary amines or secondary amines having a sterically hindered group is allowed to coexist in the reaction system. Such basic conditions can be formed by adding a basic compound to the reaction solvent, or by using a basic solvent or a mixture of a basic solvent and the non-basic solvent as the reaction solvent. be able to.

The amount of the basic compound added is at least 5 parts by weight, preferably 20 parts by weight or more, per 100 parts by weight of the reaction solvent. If the amount of the basic compound added is less than this, there will be no significant effect of increasing the molecular weight.

Any basic solvent can be used as long as it does not decompose the starting materials polysilazane and phosphorus compound. These include, for example, trialkylamines such as trimethylamine, dimethylethylamine, diethylmethylamine and triethylamine, pyridine, picoline.

In addition to tertiary amines such as dimethylaniline, pyrazine, pyrimidine, pyridazine, and derivatives thereof, pyrrole, 3-pyrroline, pyrazole, 2-pyrazolyl, and mixtures thereof can be mentioned.

The reaction temperature is preferably within a range that maintains the reaction system in a liquid state. To further increase the molecular weight of polyphosphosilazane, it is possible to carry out the reaction at a temperature above the boiling point of the solvent, but in order to prevent gelation due to thermal decomposition of polyphosphosilazane, the reaction temperature is generally below 200°C, preferably from -78°C to 150°C. It is preferable to

The pressure is preferably normal pressure. Although there are no particular restrictions on pressurization, it is not preferable to use reduced pressure because low-boiling components are distilled off and the yield decreases. The reaction time is generally about 30 minutes to one day, but in order to further increase the molecular weight of polyphosphosilazane, it is preferable to extend the reaction time.

The reaction atmosphere is preferably a dry inert atmosphere, such as dry nitrogen or dry argon, in order to prevent oxidation or hydrolysis of the raw material phosphorus compound and polysilazane or the product polyphosphosilazane.

The reaction of the present invention is advantageous in that it does not require expensive catalysts such as noble metals.

The polyphosphosilazane product and the phosphorus compound as a starting material can be separated by distillation of the phosphorus compound under reduced pressure, gel permeation chromatography, high performance liquid chromatography, or the like.

In the novel polyphosphosilazane obtained by the method of the present invention, some of the silicon-hydrogen bonds of the polysilazane are condensed with the hydrogen atoms, halogen atoms, or organic groups of the phosphorus compound, resulting in new silicon-(oxygen)-phosphorus bonds or It is a polymer having a structure in which silicon-nitrogen-phosphorus bonds are formed and/or some nitrogen-hydrogen bonds in polysilazane are also condensed with a phosphorus compound.

As can be seen from the above, the novel polyphosphosilazane of the present invention has a structure crosslinked by a crosslinking group containing a phosphorus atom represented by the following general formulas (i) to (iv).

7〒 (i) (ii) (iii)
(■) Since the phosphosilazane of the present invention is polymerized by such crosslinking groups, its molecular weight is
Naturally, the amount is increased compared to the raw material polysilazane. -For boat fishing, the novel polyphosphosilazane targeted by the present invention has a number average molecular weight of 200 to soo, oo
o, preferably 800-200,000.

In the case of the polyphosphosilazane according to the present invention, the ratio of phosphorus atoms to silicon atoms in the polyphosphone or lasane is within the range of 0.01 or more and 5 or less, and is soluble in an organic solvent.

The polyphosphosilazane obtained according to the present invention has a crosslinked structure and a larger molecular weight than the raw material polysilazane, and thus has improved coagulation properties and can be shaped quickly at room temperature. Furthermore, due to the high molecular weight, evaporation loss during high-temperature firing can be reduced, and the yield of ceramics can be improved. For example, according to the polyphosphosilazane of the present invention, a ceramic yield of 70% or more, and even 80% or more can be obtained.

The polyphosphosilazane of the present invention is easily converted into ceramics by firing under atmospheric gas or in vacuum. Nitrogen is convenient as the atmospheric gas, but argon or ammonia can also be used. Also,
A mixed gas of nitrogen, ammonia, argon, hydrogen, etc. can also be used.

The firing temperature is generally in the range of 700 to 1900°C. If the firing temperature is too low, the firing takes a long time, and if the firing temperature is too high, it is disadvantageous in terms of energy cost.

The heating rate is generally within the range of 0.1°C/min to 300°C/min. If the heating rate is too slow, firing will take a long time, and if it is too fast, thermal decomposition and shrinkage will occur all at once, causing cracks in the ceramic. Good results can be obtained by controlling the temperature increase rate to 0.5°C/min to 50°C/min in the temperature range of 600°C or lower where the thermal decomposition of polyphosphosilazane mainly occurs.

〔Effect of the invention〕

The polyphosphosilazane of the present invention is soluble in organic solvents and has excellent adhesive properties to various substrates. The polyphosphosilazane of the present invention has excellent coating properties, and a thin film can be easily formed on a substrate by simple coating such as dip coating or spray coating. The polyphosphosilazane thin film thus formed on the base material can be made into a transparent ceramic film by heat treatment. This ceramic film is characterized by excellent adhesion to the substrate, heat resistance, corrosion resistance, and abrasion resistance, as well as a high refractive index.

Therefore, the polyphosphosilazane of the present invention can be used as an optical material such as an antireflection film and a coating material for an optical material, and can also be applied as a new material in fields such as microelectronics, aerospace industry, automobile industry, and building materials. be able to.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.

Reference Example 1 A four-loop flask with an internal volume of IQ was equipped with a gas blowing pipe, a mechanical stirrer, and a dewar condenser. After the inside of the reactor was replaced with deoxygenated dry nitrogen, degassed dry pyridine 490- was placed in a four-bottle flask and cooled on ice. Next, when 51.6 g of dichlorosilane was added, a white solid adduct (SiH2CQ2.2C,H,N) was formed.
was generated. The reaction mixture was ice-cooled, and while stirring, 51.0 g of purified ammonia was blown into the reaction mixture through a sodium hydroxide tube and an activated carbon tube.

After the reaction is completed, the reaction mixture is centrifuged, washed with dry pyridine, and further filtered under a nitrogen atmosphere to obtain a filtrate 8.
I got 50-. The solvent was distilled off from the filtrate 5- under reduced pressure to obtain 0.102 g of resinous solid perhydropolysilazane.

The number average molecular weight of the obtained polymer was 980 as measured by GPC. Also, the IR of this polymer
Examining the (infrared absorption) spectrum (solvent: dry 0-kylene; concentration of perhydropolysilazane: 10.2 g/12), the wave number (cm-'') was 3350 (apparent extinction coefficient ε: 0.557 ug-1 cm- 1 and 1175 NH
Absorption based on SiH of 2170 (ε=3.14); Absorption based on SiH and SiNS1 of 1020 to 820. In addition, the HNMR (proton nuclear magnetic resonance) spectrum (6
When examining the 0 MHz solvent CDC4□/reference material TMS), it was confirmed that both showed broad absorption. i.e. 64.8 and 4.4 (br, SiH); 1.5 (
br.

Absorption of NH) was confirmed.

Reference example 2 The reaction was carried out using the same apparatus as in Reference Example 1.

That is, 450 kg of degassed dry tetrahydrofuran was placed in the four-loaf flask shown in Reference Example 1, and cooled in a dry ice-methanol bath. Next, dichlorosilane 46
．． Added 2g. This solution was cooled, and 44.2 g of anhydrous methylamine was blown into the solution as a mixed gas with nitrogen while stirring.

After the reaction was completed, the reaction mixture was centrifuged, washed with dry tetrahydrofuran, and then filtered under a nitrogen atmosphere to obtain filtrate 820-. When the solvent was distilled off under reduced pressure, 8.4 g of viscous oily N-methylsilazane was obtained. The number average molecular weight of the obtained polymer was 1100 as measured by GPC.

Reference Example 3 A four-roster stirrer with an internal volume of IQ was equipped with a gas blowing pipe, a mechanical stirrer, and a dewar condenser.

After purging the inside of the reactor with deoxygenated dry nitrogen, 300 ml of dry dichloromethane and 24.3 g (0,211 mol) of methyldichlorosilane were placed in a four-bottle flask and cooled on ice. While stirring, 18.1 g of purified ammonia (1,0
6 mol) was injected.

After the reaction was completed, the reaction mixture was centrifuged, washed with dry dichloromethane, and further filtered under a nitrogen atmosphere. The solvent was distilled off from the filtrate under reduced pressure to obtain 8.81 g of colorless and transparent methyl (hydro)silazane. The number average molecular weight of this product was 380 as measured by GPC.

Reference Example 4 A pyridine solution of the perhydropolysilazane obtained in Reference Example 1 (concentration of perhydropolysilazane: 5°25% by weight)
) was placed in a pressure-resistant reaction vessel with an internal volume of 300III2, and aluminum triisopropoxide 13.
Add Og (0,0636moQ) and heat at 120℃ in a closed system.
The reaction was carried out with stirring for 3 hours. After the reaction was completed, the reaction mixture was filtered to obtain polyaluminosilazane as a filtrate.

Example 1 A four-loop flask with an internal volume of IQ was equipped with a gas blowing pipe, a mechanical stirrer, and a dewar condenser. After purging the inside of the reactor with deoxygenated dry nitrogen, 410 m12 of trimethyl phosphite (3,50+++oΩ) was added.
were placed in a flask, 300% of the pyridine solution of perhydropolysilazane obtained in Reference Example 1 (concentration of perhydropolysilazane = 5.0% by weight) was added, and the mixture was stirred at 80°C for 3 hours under a nitrogen stream. The reaction was carried out. After the reaction was completed, the solvent was replaced with 0-xylene, and the reaction mixture was centrifuged and filtered to obtain a filtrate. The solvent in the filtrate is heated to a pressure of 1
When the residue was distilled off under reduced pressure at 0 mmHg and a temperature of 40°C, a brown powder with no solvent resolubility was obtained.

The number average molecular weight of the reaction product was measured by GPC.
It was 1515. When we analyzed its IR spectrum, we found that the wave number was 3400cm-'' and 1200cm-1.
absorption based on SiH at 2200 cm-', absorption based on Si) I and NSiN from 1020 to 820 cm-', 2950 cm-'', 2850c++-'',
Absorption based on C1 at 1460 cm-1, 108108
Absorption based on SiO was observed in O''.

The above reaction product was heated in ammonia to 1000° C. at a heating rate of 3° C./min and thermally decomposed to obtain a brownish-gray solid at a yield of 77.1% by weight. The values of elemental analysis of this solid are, on a weight basis, Si: 44.2%, N: 21.1%
, O; 28.5%, O; 3.43%.

Example 2 The 0-xylene solution of polyphosphosilazane obtained in Example 1 (polyphosphosilazane concentration: 5.0% by weight) was coated on a silicon substrate in a nitrogen atmosphere using a spin coater. This coating thin film was heated to 800°C in nitrogen.
A transparent Si--N--P ceramic thin film was obtained by heating at a heating rate of 3° C. for 7 minutes.

When the thickness and refractive index of this ceramic thin film were measured using an ellipsometer, the film thickness was 958 mm and the refractive index was 1.9.

Example 3 A four-loop flask with an internal volume of 1001II2 was equipped with a gas blowing tube, a mechanical stirrer, and a dewar condenser. After purging the inside of the reactor with deoxidized dry nitrogen, four 0-xylene solutions of perhydropolysilazane obtained in Reference Example 1 (concentration of perhydropolysilazane = 5.0% by weight) 10- were placed in a flask. Further, hexamethylphosphorustriamide 2d (0.01 moQ) was added, and the reaction was carried out with stirring at 80° C. for 3 hours under a nitrogen stream. After cooling to room temperature, the solvent of the reaction product was reduced to a pressure of 10
When the residue was distilled off under reduced pressure at +imHg and a temperature of 40°C, a brown powder was obtained.

The number average molecular weight of the reaction product was measured by GPC.
It was 2304. Analysis of the IR spectrum revealed that the wave number was 3400cm-'', absorption based on NH at 1200cm-', absorption based on SiH at 2200cm-'', absorption based on SiH and NSiN at 1020-850co+-1, and absorption based on SiH and NSiN at 2900cm-1 and 2800cm-1. 1,1
480cm-", absorption based on CH at 1460cm-1, and absorption based on CN at 1080c+o-1. Furthermore, the "HNNH spectrum (CDCQ, T
MS internal standard) was analyzed and found to be 64.7 ppm+(
br, SiH2), δ4,3ppm (br.

5L)13), δ2.7ppm, δ2.5ppm (C
H, N), 1.3 ppm (br.

Absorption of NH) was observed.

This reaction product is heated to 1000°C in ammonia at a temperature increase rate of 3°C/min to thermally decompose the black solid to 9
Obtained with a yield of 2.6% by weight. The values of elemental analysis of the obtained selacs are based on weight: Si: 58%, N: 24°4
%, C: 4.3%, 0: 9.22%, P: 4%.

In addition, a 0-xylene solution of this reaction product (polyphosphosilazane concentration: 5.0% by weight) was coated on a silicon substrate using a spin coater in the same manner as in Example 2, and heated to 800°C at a heating rate of 3°C/min. As a result, the thickness of the obtained ceramic thin film was 940 mm, and the refractive index was 1.8.

Example 4 A four-bottle flask with an internal volume of 200 cm was equipped with a gas blowing pipe,
Equipped with mechanical stirrer and dewar condenser. After replacing the inside of the reactor with deoxygenated dry nitrogen, the concentration of the pyridine solution of perhydropolysilazane (perhydropolysilazane) obtained in Reference Example 1: 5.0% by weight)3
0d was placed in a flask, 21.7 nm of a pyridine solution of phosphonitric chloride trimer (concentration of phosphonitric chloride trimer: 3.70% by weight) was added, and the reaction was stirred at room temperature for 25 hours under a nitrogen stream. went. After the reaction was completed, the solvent was replaced with 0-xylene and filtered to obtain a filtrate.

The number average molecular weight of polyphosphosilazane in the filtrate was measured by GPC and found to be 1299. When the IR spectrum of the phosphosilazane was analyzed, the wave number was 3400 cm.
-'', 1200cl-' absorption based on N) I, 220
Absorption based on 0 cm SiH, 102102O-820”
Absorption based on SiH and NSiN, 1220 cm
Absorption based on PN was observed.

Example 5 The 0-xylene solution of polyphosphosilazane obtained in Example 4 (concentration of polyphosphosilazane: 10% by weight) was coated on a glass substrate by dip coating. This coated thin film was heated to 200℃ in nitrogen at a rate of 3.
Heating was performed at a rate of °C/min to obtain a transparent Si-N-P film.

The thickness and refractive index of this ceramic thin film were 5600 and 1.6.

Example 6 A four-bottle flask with an internal volume of 100 mm was equipped in the same manner as in Example 1, and the inside of the reactor was purged with dry nitrogen. A γ-picoline solution of N-methylpolysilazane obtained in Reference Example 2 (N
- Four 30 d of methylpolysilazane (concentration 10.0% by weight) were placed in a Lough flask, and 1.2+all (0.01 mon) of trimethyl phosphite was added, and the reaction was carried out with stirring at 80°C for 3 hours under a nitrogen stream. . The produced brown precipitate was centrifuged, the upper channel was filtered, and the solvent of the filtrate was distilled off under reduced pressure in the same manner as in Example 1, to obtain a dark brown rubbery solid.

In addition, a γ-picoline solution of this reaction product (polyphosphosilazane with a concentration of 5.0% by weight) was coated on a silicon substrate using a spin coater in the same manner as in Example 2, and heated to 800°C at a heating rate of 3°C/min. The thickness of the obtained ceramic thin film was 876 mm, and the refractive index was 1.8.

Example 7 100 - of the 0-xylene solution of methylhydropolysilazane obtained in Reference Example 3 (concentration of methylhydropolysilazane 6.0% by weight) was placed in a pressure-resistant reaction vessel with an internal volume of 300ml, and 4.2g of phosphorus pentachloride ( 0.02mol12) was added thereto, and the reaction was carried out in a closed system at 120°C with stirring for 3 hours.

The white precipitate was filtered off, and the solvent of the filtrate was distilled off under reduced pressure in the same manner as in Example 1, to obtain 4.8 g of a colorless and transparent rubbery solid.

Example 8 The 0-xylene solution of polyphosphosilazane obtained in Example 7 (concentration of polyphosphosilazane 10% by weight) was coated on a silicon substrate by brushing under a nitrogen atmosphere. This coated thin film was heated in nitrogen to 800°C at a heating rate of 30°C/min to obtain a transparent Si-N-P thin film. The thickness and refractive index of this ceramic thin film are 95
00 people and 1.8.

Example 9 A four-hole flask having an internal volume of 100 d was equipped in the same manner as in Example 1, and the inside of one reactor was purged with dry nitrogen.

0-xylene solution of polyaluminosilazane obtained in Reference Example 4 (concentration of polyaluminosilazane 5.0% by weight) 4
0- into a flask, and then add 4.0 Ilil of hexamethylphosphorustriamide! (0.02moΩ)
was added, and the reaction was carried out with stirring at 80° C. for 3 hours under a nitrogen stream. When the reaction product was filtered and the solvent of the obtained filtrate was distilled off under reduced pressure in the same manner as in Example 1, 1.5 g of yellow solid was obtained.
was gotten.

An 0-xylene solution of this reaction product (polyphosphoaluminosilazane concentration: 5.0% by weight) was coated on a silicon substrate using a spin coater in the same manner as in Example 2.
When heated to a temperature of 3° C./min, the resulting ceramic thin film had a thickness of 960 mm and a refractive index of 1.8.

Comparative example 1 of the perhydropolysilazane obtained in Reference Example I.

- A xylene solution (concentration of perhydropolysilazane: 5.0% by weight) was coated on a silicon substrate using a spin coater under a nitrogen atmosphere. This coating film was heated in nitrogen at a heating rate of 3°C/min to goo°C to obtain a transparent silicon nitride thin film. When the film thickness and refractive index of this ceramic thin film were measured using an ellipse meter, the film thickness was 91.
0 people, and the refractive index was 1.6.

Comparative example 2 of perhydropolysilazane obtained in Reference Example 1.

-Xylene solution (concentration of perhydropolysilazane: 10
00% by weight) was coated on a glass substrate by dip coating. This coated thin film was coated in nitrogen for 20 minutes.
A transparent silicon nitride thin film was obtained by heating to 0° C. at a heating rate of 3° C./min. The thickness and refractive index of this ceramic thin film were 6100 and 1.3, respectively.

Comparative Example 2 0-xylene solution of methylhydropolysilazane obtained in Reference Example 3 (concentration of methylhydropolysilazane: 6.0
% by weight) was coated onto a silicon substrate by brushing under a nitrogen atmosphere. This coated thin film was heated in nitrogen to 800° C. at a heating rate of 3° C./min to obtain a transparent silicon nitride thin film. The thickness and refractive index of this ceramic thin film were 9130 and 1.6.

Claims (5)

[Claims] (1) In polysilazane, the following general formulas (i) to (i
v) contains at least one type of crosslinking bond represented by
A polyphosphosilazane having a phosphorus/silicon atomic ratio in the range of 0.01 to 5 and a number average molecular weight of about 200 to 500,000. (i)▲There are mathematical formulas, chemical formulas, tables, etc.▼; (ii)▲
There are mathematical formulas, chemical formulas, tables, etc. ▼; (iii) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼; (iV
) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, R^6 is a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group, a cycloalkyl group, an aryl group, an alkoxy group, It is an alkylamino group, hydroxyl group, or amino group, and R^7 is a residue bonded to the nitrogen atom of a group having a nitrogen atom among R^6) (2) A polysilazane having at least a SiH bond or a SiNH bond in the molecule and having a number average molecular weight of about 100 to 50,000 is reacted with a phosphorus compound represented by the following general formulas (I) to (V) to produce phosphorus/ Silicon atomic ratio is 0.0
within the range of 1 to 5, and the number average molecular weight is 200 to 5
A method for producing polyphosphosilazane, characterized by obtaining polyphosphosilazane having a molecular weight of 0.00,000. (I)P(R^4)_3 (II)((R^4)_2PN)_n (III)P(R^4)_5 (IV)P_2O_5 (V)OP(R^4)_3 (These formulas In the formula, R^4 may be the same or different, and is a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group, a cycloalkyl group, an aryl group, an alkoxy group, an alkylamino group, a hydroxyl group. or an amino group, n is an integer of 2 or more) (3) The polysilazane mainly has the general formula (VI): ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (VI) (In the formula, R^1, R^2, R^3 are hydrogen atoms, alkyl groups, alkenyl group, cycloalkyl group, aryl group, or a group other than these groups in which the group directly bonded to silicon is carbon,
It represents an alkylsilyl group, an alkylamino group, or an alkoxy group, in which at least one of R^1, R^2, and R^3 is a hydrogen atom) and has a number average molecular weight of approximately 3. The method of claim 2, wherein the polysilazane has a molecular weight of 100 to 50,000. (4) Ceramics containing at least silicon, nitrogen and phosphorus and having a phosphorus/silicon atomic ratio in the range of 0.01 to 5, the ceramics having the formula Si-0-P, Si-
A phosphorus-containing ceramic characterized by having a bond represented by P or PN. (5) The phosphorus-containing ceramic according to claim 3, wherein the ceramic is a transparent thin film having a refractive index of at least 1.6.