JPH0643494B2 - Process for producing linear thermotropic copolymer composed of aromatic azomethine type mesogenic unit and polysiloxane spacer - Google Patents

Description

The present invention relates to an essentially linear thermotropic copolymer consisting of aromatic azomethine (CH = N) type mesogen units and diorganopolysiloxane bending spacer (chain) units. The novel copolymer of
Prepared from diorganopolysiloxanes and aromatic primary diamines, each of which is α, ω-disubstituted by a group containing a formylphenyl residue.

PRIOR ART AND PROBLEMS TO BE SOLVED BY THE INVENTION Linear thermotropic copolymers containing mesogenic units separated by flexing spacers are compared to polymers in which mesogenic units are directly linked to each other via a non-mesogenic rigid binding medium. Lower phase transition temperature (especially glass transition temperature Tc and purification where the intermediate phase becomes anisotropic (clarificat
Ion) temperature Tc) is of interest.

Linear thermotropic copolymers are known that contain the following as spacers: Polymethylene groups (A. Roviello et al., J. Polym. Sci., Pol.
ym.Lett.Ed. 13 , 455, (1975)), a diorganopolysiloxane group (IUPA by C. Aguilera et al.
C Macro, Florence Preprints, 3 , 306, 1980)), mixing of aliphatic and polysiloxane groups (BW Jo et al.
Eur. Pol. J., 18 , 223, (1982).

Thermotropic polyesters containing diorganopolysiloxane spacers are of particular interest because they have a significantly lower phase transition temperature compared to thermotropic polymers of the same type in which the spacers are polymethylene groups (C. Aguilera et al. Makromol. Chem. 184 , 253 ( 1983)). However, careful examination of the molecular weights (n) obtained with these thermotropic polyesters of the prior art reveals that they have been treated with low molecular weight (on the order of 3000-4000 g / mol) thermotropic oligomers, such molecular weights It turns out that it is not suitable for use as an engineering plastic.

The applicant company operating in this technical field has 4
Higher molecular weight (more than 000 g / mol, reaching 10,000 g / mol and exceeding 10,000 g / mol (
An essentially linear thermotropic copolymer containing a diorganopoesiloxane spacer having n) has been developed. The above molecular weights make the thermotropic copolymers perfectly compatible for use as engineering plastics.

These thermotropic copolymers have the formula: [In the formula, the symbols A are the same, and each is a single bond or -O-, The symbol B ₁ represents a group of —CH═N— or —N═CH—, while the symbol B ₂ is different from B ₁ and represents a —N═CH— group (B
₁ is -CH = N-) or -CH = N- group (B ₁
Is -N = CH-), and symbol D is a group of the following formula: (In the formula, y is an integer in the range of 0 to 2, and the symbol E is a single bond or -CH = N-, -N = CH when y = 1.
-, Or And when y = 2, a single bond, Or In which R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are the same or different and are monovalent selected from linear or branched alkyl groups containing 1 to 12 carbon atoms. Hydrocarbon groups of (by at least one chlorine, bromine or fluorine atom with respect to these groups or
Optionally substituted by a CN group); at least one alkyl and / or alkoxy group containing 1 to 4 carbon atoms or a phenyl group optionally substituted by at least one chlorine atom, the symbol X being An integer in the range 2 to 8 and the symbol n
Is an integer or a fraction in the range of 0 to 50].

These thermotropic copolymers are new products and were filed by the applicant company on the same day as the present invention (French application 89/07221) and consist of "aromatic azomethine type somogen units and polysiloxane polymer spacer units. It is described and claimed in a French patent application (French application 89/07220) entitled "Linear thermotropic copolymers and methods for their preparation". According to the above parallel application, the thermotropic copolymer comprises a repeating unit of the formula (I) in which B ₁ is —CH═N— and B ₂ is a —N═CH— group in the structure (I) It is obtained by using a method comprising two steps of (a) and (b) below: (a) a method known per se, (i) a bifunctional compound of the following formula: ; (Wherein the symbols x and A have the meanings given above in relation to the formula (I)), and (ii) a diamine compound of the following formula: H ₂ N-D-NH ₂ (IV) (wherein , The symbol D has the meaning given above in relation to formula (I)), and is then obtained from the reaction mixture in a manner known per se by a precursor of the mesogen of formula (II) By separating the body monomers in the pure state, the formula: (Wherein the symbols x, A and D have the meanings given above in relation to formula (I))
-Synthesizing a disubstituted mesogen precursor monomer, and (b) operating under anhydrous conditions in an oxygen-free inert atmosphere and in the presence of a hydrosilyation catalyst, iii) α, ω-bis (hydro) diorganopolysiloxane of the following formula; (Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ and n have the general or preferred meanings given above in relation to formula (I)), and (iv) At the end of step (a), the formula (I
Reacting the mesogen precursor monomer of I), then And / or by carrying out the polyhydrosilylation reaction by separating the desired thermotropic copolymer from the reaction mixture in a manner known per se immediately after the complete disappearance of CH ₂ ═CH—. The thermotropic copolymer of is synthesized.

The present invention finds novel application where these copolymers comprise in their structure recurring units of formula (I) in which B ₁ is —CH═N— and B ₂ is —N═CH—. We have found a manufacturing method, which forms the subject of the invention.

According to this novel process, a diorganopolysiloxane, each α, ω-disubstituted by a group containing a p-formylphenyl residue, is first prepared and then used in a polymerization reaction with an aromatic primary diamine. .

More specifically, the method of the present invention comprises repeating units of the formula: (In the formula, symbols X, A, D, R _{1 to} R ₆ and n represent the above formula (I).
Having the meanings given above in relation to) in their structure, a process for the production of an essentially linear thermotropic copolymer comprising steps (c) and (d)
Is continuously performed.

(c) under anhydrous conditions, in an inert atmosphere containing no oxygen, at a temperature not exceeding 80 ° C. and in the presence of a hydrosilylation catalyst, (1) α, ω-bis ( Hydro) diorganopolysiloxane; (Wherein R _{1 to} R ₆ and n have the meanings given above in relation to formula (I)), and (2) a bifunctional compound of the formula: Where the symbols x and A have the meanings given above in relation to formula (I), and then from the reaction mixture: And / or immediately after the CH ₂ ═CH-functional group has completely disappeared, the siloxane precursor monomer is separated off immediately below so that each α, ω-disubstituted by a group containing a p-formylphenyl residue. The diorganopolysiloxane species of formula: Synthesizing a siloxane precursor monomer containing in the structure, wherein the symbols A, X, R _{1 to} R ₆ and n have the above meanings in relation to formula (I), and (d) By a method known per se, (3) an aromatic diamine compound represented by the following formula; H ₂ N-D-NH ₂ (IV) (wherein the symbol D has the above meaning in relation to the formula (I)) And (4) reacting with the siloxane precursor monomer obtained at the end of step (c), and then immediately after the complete disappearance of the aldehyde and / or NH ₂ -functional group, a method known per se. The polyimination reaction is carried out to synthesize the desired thermotropic copolymer by separating the desired thermotropic copolymer from the reaction mixture according to.

As mentioned above, in step (c), the hydrosilation reaction of the bifunctional reactant (2) of formula (III) can be carried out in a heterogeneous mixture and without solvent.

The operations are preferably carried out in a homogeneous mixture by adding the starting reactants to a solvent or solvent mixture common to the reactants and the desired product. The solvent used must be anhydrous and suitable solvents may in particular include tetrahydrofuran, benzene, chlorobenzene, toluene and acetonitrile.

The hydrosilylation reaction is generally performed at 20 ° C to 12 ° C.
It is carried out at a temperature in the range of 0 ° C, preferably in the range of 60 ° C to 80 ° C. The bifunctional reactant (2) is generally In an amount equal to 2 moles per mole of reactant (1) containing. The amount of reactants (1) and (2) is defined as reactant (2) / reactant
It is not outside the scope of the present invention to use the molar ratio of 1) in the range of 1.9 / 2 to 2.1 / 2, for example.

The α, ω-bis (hydro) diorganopolysiloxane (1) of the formula (V) used is a well-known product in the silicone industry, and in some cases (fully alkylated compounds): It is commercially available. They are, for example, French patent A1-2,486,952 and French patent A5-.
No. 2,058,988. If these products are not commercially available, they can be converted, for example, into suitable α, ω-
It can be prepared by cationically polymerizing a bishydroxylated diorganopolysiloxane oil followed by a chain transfer reaction, especially with a reagent such as dihydrotetraalkyldisiloxane. In these compounds of formula (V), when n is greater than 1, it is treated as a compound having a polymerizable structure, and a single polymer species (so-called monodisperse structure, in which n is an integer) or It is possible to have any of the mixtures of polymerizable species of the same chemical structure with different numbers of repeating units (so-called polydisperse structures, where n is often a fraction).

The bifunctional reactant (2) of formula (III) comprises known products which can be easily prepared. For example, Is obtained by the condensation reaction of 4-hydroxybenzaldehyde and allyl bromide, Is obtained by the same type of reaction between 4-hydroxybenzaldehyde and acryloyl chloride.

For hydrosilylation catalysts it is possible in particular to use the following compounds, in particular elemental platinum, hexachloroplatinic acid in the hydrated form or else elemental platinum and α, ω-bis (vinyl) diorgano. Complexes based on siloxane type ligands, metal carbonyls such as cobalt carbonyl or nickel carbonyl. The preferred catalysts of the present invention are complexes based on hexachloroplatinic acid or the elemental platinum and 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, usually Kersted.
rsted) catalyst. The amount of catalyst used is the following ratio: Is generally in the range of 0.05 × 10 ^{−4 to} 20 × 10 ⁻⁴ and preferably in the range of 0.2 × 10 ^{−4 to} 5 × 10 ⁻⁴ .

The catalyst may be introduced into the reaction mixture either in its naturally occurring form or in the form of a suitable dilution or solvent suspension or solution. In the case of a preferred catalyst consisting of hexachloroplatinic acid, it is, for example,
It is commonly used in the form of a solution of a saturated aliphatic monoalcohol such as isopropanol. In the case of a preferred catalyst consisting of a complex based on the element platinum, it is, for example, benzene, toluene, cyclohexane or n-.
It is commonly used in the form of a solution of a hydrocarbon such as hexane.

To actually carry out step (c), first charge the reactants (2) and then the solvent of choice to the reactor and heat the reactants with stirring to the temperature adopted within the above temperature range. To do. Then the catalyst is added. Next, bis (hydro)
The siloxane reactant (1) can optionally be introduced into the stirred and heated reactants in the form of a solution of one and / or more solvents that can be used (wherein the reactants are selected It is advantageous to include one of the selected solvents or one of the selected solvents which can be used simultaneously with the starting reactants). This introduction is gradually carried out over a range of, for example, 30 minutes to 15 hours. The introduction of the bis (hydro) siloxane reactant (1) is preferably carried out while at the same time ensuring that dry and oxygen-free nitrogen is dispersed in the reactants.

At the end of the reaction, when the desired siloxane precursor monomer is obtained in solution, it can be precipitated by adding a non-solvent or mixed non-solvent to the reaction mixture and the precipitated copolymer can be isolated. The siloxane precursor monomer can also be obtained by removing the solvent from the reaction mixture by vacuum distillation.

The siloxane precursor monomers thus prepared are obtained, in particular, by spectroscopic studies (infrared absorption and proton and C ¹³ nuclear magnetic resonance), by steric exclusion chromatography and by chemical analysis of the terminal aldehyde functions. It is a new product whose structure is characterized by determination.

We have found that, especially when the reactant (2) has the formula (III) in which the symbol A represents an oxygen bridge, this first step (c) is a siloxane precursor monomer structure in which the unsuitable repeat unit of the formula: ; as well as (In the formula, symbols R _{1 to} R ₆ and n have the above meanings in relation to the formula (I), and R is It is located in the side reaction that produces

It is believed that these unsuitable siloxane species can be obtained as a result of:

・ In the case of the seed of formula (VIII), according to the following formula, But Cleaves to reform the ether bond of reactant (2) by the formation of; In the case of seeds of formula (IX), a monofunctional siloxane of the formula: of O-silylation reaction of the aldehyde function of the precursor monomer according to formula (VII) according to

As is usual, the maximum amount of unsuitable siloxane species of formula (VIII) and formula (IX), when formed, is
Not more than 12 mol% (species (VIII) species) and 7 mol% (formula (IX)), based on the sum of the conforming species of I) plus the unsuitable species of formula (VIII) and formula (IX). Any of the above unsuitable siloxane species, when formed, will result in unsuitable repeat units of the following formula in the structure of the desired thermotropic copolymer: When the species of formula (VIII) is the initiator ; Where the symbols x, R _{1 to} R ₆ and n have the meanings given above in relation to formula (I); when an initiator of the species of formula (IX); Inappropriate units of formula (X) and formula (XI) are based on the sum of the conforming species of formula (XI) + the unsuitable species of formula (X) and formula (XI), whichever it is formed. 12 mol% [Formula (X)
Seed] and 7 mol% [formula (XI)].

Regarding the step (d) in which the polyimination reaction takes place, this is carried out in bulk, under atmospheric pressure and then optionally under reduced pressure, generally with 1 mol of the diamine (3) and 1 mol of the siloxane precursor monomer (4). It can be carried out by heating and the operation is carried out, for example, at a temperature between 50 ° C. and 200 ° C., for example for 20 minutes to 15 hours. Reactant
The molar ratio of (3) / reactant (4) is, for example, 0.90 / 1 to 1.1 / 1.
It is not outside the scope of the invention to use an amount of reactants in the range.

The polyimination reaction is preferably carried out in the presence of a solvent or solvent mixture common to the reactants and the desired copolymer, depending on the solubility of the reactants, expressed as g of reactants per 100 cm ^{3 of} solvent, depending on the solubility of the reactants. Note that the concentration should be greater than 5% and exactly 6-30% or higher. Suitable solvents are, in particular, benzene, chlorobenzene, toluene and xylene. With respect to the amount of reactants selected, the amounts given above for use in bulk form. With regard to the reaction temperature, in this case also 50-15
It is present in the range 0 ° C., in which case it is advantageous to correspond to the boiling point of the solvent used. In practice, the polyimination reaction is carried out by continuously removing the polyimination water by azeotropic distillation. This azeotropic distillation is carried out slowly over a period of time, for example in the range 3 to 20 hours. To carry out this distillation under suitable conditions, the amount of solvent utilized to produce this azeotropic distillation is kept constant in the reaction group by continuously introducing an amount of solvent equivalent to the solvent to be evaporated. It is advantageous to do It should be known that the reaction mixture can be introduced with a particular solvent such as acetonitrile or methylsulfoxide if it is necessary to increase the solubility of the reactants and products in the reaction medium. At the end of the reaction,
The desired copolymer can be obtained in the form of a solution and the copolymer can be precipitated by adding a non-solvent or mixed non-solvent to the reaction mixture. It is also possible to obtain the copolymer by removing the solvent from the reaction mixture by distillation under reduced pressure.

As a thermotropic copolymer which is a preferred representative example of the compound produced according to the method of the present invention, a compound of formula (VI)
In the above, the symbols A are the same, and each is a single bond or -O-, And the symbol D is a group of the following formula: (In the formula, y is an integer in the range of 0 to 2, and the symbol E is a single bond or -CH = N-, -N = CH when y = 1.
-, Or And when y = 2, a single bond, Or In which R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are the same or different and are selected from linear or branched alkyl groups containing 1 to 6 carbon atoms. Where the symbol X is an integer equal to 2 or 3 and the symbol n is an integer or fraction in the range 1 to 30 which may include copolymers in the structure of the repeating unit of formula (VI).

More preferred specific thermotropic copolymers prepared according to the method of the invention may include those in the structure of which repeat units of formula (VI) satisfy the following conditions: A is And D has the above meaning in relation to formula (I), R _{1 to} R ₆ are the same or different and each represents a linear alkyl group containing 1 to 3 carbon atoms or a phenyl group, x is 2
And n is in the range 1-30; A is -O-, D has the above meaning in relation to formula (I), R _{1 to} R ₆ are the same or different and each is a linear alkyl group containing 1 to 3 carbon atoms. Or a phenyl group, x is 3 and n is in the range 1-30.

Specific examples of particularly representative thermotropic copolymers produced according to the method of the present invention include, for example:
Mention may be made, in the structure, of which the repeating unit of formula (VI) fulfills the following conditions: A is -O- and D is _3. R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , and R ₆ are methyl groups, x is 3 and n is in the range 1-20; A is -O- and D is _4. R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , and R ₆ are methyl groups, x is 3 and n is in the range 1-20; A is -O- and D is And R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , and R ₆ are methyl groups, x is 3 and n is in the range 1-20.

The thermotropic copolymers prepared according to the invention have a high molecular weight of more than 4000 g / mol, for example 10,000-20.
Copolymers with such a molecular weight having a number average molecular weight n that can reach values as high as the range of 000 g / mol exhibit mechanical properties that can be used in the field of engineering plastics.

Another characteristic of the copolymers prepared according to the invention is that they show liquid crystals (mesophases) at an average temperature of, for example, 50 ° C. to 270 ° C., depending on the structure of the copolymer, without showing the risk of thermal decomposition. To form a phase. Cycle temperature (23
The temperature with respect to the configuration and the anisotropy region with respect to (.degree. C.) (the range which can be indicated by the difference of Tc-Tg in the case of amorphous copolymers) can be conveniently adjusted especially by the following various structural parameters.

The attribute of the symbol D shown in formula (VI); For example, it is observed that an increase in the number of phenyl groups leads to an increase in the injection of the phase transition temperature.

Length n of the flexible polysiloxane spacer shown in formula (VI); for example, increasing n value is observed to result in decreasing phase transition temperature value.

Siloxane spacer dispersity (see below for method of making copolymers according to the invention): For example, polydispersity can lower the value of the phase transition temperature relative to the phase transition temperature produced by the use of monodisperse siloxane spacers. Is observed.

The following examples illustrate how the invention can be carried out, but they do not limit the invention in any way.

In these examples, thermotropic copolymers prepared according to the method of the invention were identified, inter alia, by spectroscopic studies (infrared absorption and proton and C ¹³ nuclear magnetic resonance). The molecular weight of these copolymers;
It was determined using various consistent calibrations (including tetrahydrofuran solvent, polystyrene). The thermotropic property is linked to the 9900 central processing unit
It was measured by differential thermal analysis (DSC) on a DuPont instrument containing the C910 module. It was observed by means of a polarizing microscope equipped with a heating stage with which the existing phase properties can be identified and examined by means of X-ray diffraction.

Examples Four thermotropic copolymers containing repeating units of the formula below in their structure are described in these examples: (In the formula, in the first three polymer groups, D is And n is 1, 4 and 15 (Examples 4, 5 and 6), and in the fourth polymer, D is And n is 1 (Example 7)).

These copolymers are obtainable using the process according to the invention by starting with the appropriate combination of reactants (3) and (4) below.

The reaction product (3) is represented by the following expression M1; And M2; (D is When) M1: And M2: Two aromatic diamine compounds H ₂ N-D represented by
It encompasses the -NH _2.

The reaction product (4) has the following formula: Where n corresponds to the values n = 1, n = 4 and n = 15) of the diorganooligosiloxane species (depending on the CHO group α,
ω-difunctionalized) containing three siloxane precursor monomers. In the following, each siloxane precursor monomer (4) is designated by the symbol In and n has the value of the symbol n in formula (XIII). Therefore, the siloxane precursor monomers I1, I4 and I15 are used.

Also, in the following, the four copolymers produced are:
It is represented by the following expression; Examples 4, 5 and 6: M1I.
1, M1I4 and M1I15 and Example 7: M2I
1. Examples 1-3 Preparation of siloxane precursor monomers I1, I4 and I15 according to the operating method of step (c) of the method of the present invention.

1. Equipment: Operation is 100 cm ³ equipped with heating system with heat transfer medium, magnetic stirring system, dropping funnel, reflux condenser and system for dispersing dry nitrogen without oxygen.
In the reactor of.

2. General procedure: First, 16.2 g (0.1 mol) of p-allyloxybenzaldehyde and 65 cm ³ of anhydrous toluene are charged to the reactor. Turn on the stirrer and heat the reactants to 75 ° C.
Heat to the temperature of. Then the catalyst is added. The catalyst is a Karstedt catalyst, which is an n-hexane solution having a concentration of 10.1% (expressed in terms of weight g of elemental platinum based on the volume cm ³ of the solution). 6.2 microliters of this solution are injected with a syringe (ratio: number of gram atoms of the element Pt / mol of α, ω-bis (hydro) oligosiloxane equal to 0.32 × 10 ⁻⁴ ).

Dry oxygen free nitrogen was dispersed in the reactants and 0.05 mol of α, ω-bis (hydro) of the formula
Oligosiloxane; (Where n is 1 (Example 1), 4 (Example 2) and 15
(Example 3) and a solution containing 20 cm ³ of anhydrous toluene is continuously poured into the stirred material. The introduction of bis (hydro) oligosiloxane is carried out for 2 hours while maintaining the temperature at 75 ° C. At the end of this time, the disappearance of the -Si-H functional group is confirmed by infrared absorption, and the desired siloxane precursor monomer In is removed by distillation to recover the toluene.

3. Results for Examples 1-3: Obtained siloxane precursor monomers I1, I4 and I1.
5 is a slightly colored solid. The structures of these products, confirmed by spectroscopic studies (infrared absorption and proton and C ₁₃ nuclear magnetic resonance), by steric exclusion chromatography and by chemical determination of the terminal aldehyde functional groups, are n = 1,4 above. And 15 in agreement with the essential representation of the species of formula (XIII).

It can be seen that the siloxane monomer I1 contains 17 mol% of unsuitable species, the n of which is equal to 556.5 g / mol. It can be seen that the siloxane monomer I4 contains less than 5 mol% of unsuitable species and its n is equal to 770 g / mol. For the siloxane monomer I15, it is found that it contains less than 5 mol% of unsuitable species, the n of which is equal to 1640 g / mol.

The molar yields of precursor monomers I1, I4 and I15 are 95
%taller than.

Examples 4 to 7 Thermotropic copolymers M1I1, M1I according to the operating method of step (d) (polyimination reaction) of the method of the present invention.
Production of 15 and M2I1.

1. Equipment: No. 1: The operation is carried out in a 100 cm ^{3 three-} neck round bottom glass flask equipped with a heating system using a heat transfer fluid, a magnetic stirring system, a dropping funnel and a distillation column with a downstream condenser and a receiver.

No. 2: The operation is carried out in a 100 cm ³ cylindrical glass reactor equipped with a heating system using a heat transfer fluid, a mechanical stirring system and a system providing vacuum.

2. General procedure: Embodiment No. 1: polyimination reaction is carried out in solvent using instrument No. 1. Charge 0.01 mole of aromatic diamine compound M (reactant (3)), 0.01 mole of siloxane precursor monomer In and 60 cm ³ of toluene to the reactor. Switch on the stirrer and apply heat, making sure that the toluene distills slowly and slowly. As soon as the distillation starts, fresh anhydrous toluene is introduced into the reaction mixture so that the volume of solvent in the reactor stabilizes at 20 cm ³ .
Distillation is continued under these conditions for 12 hours. At the end of this time, the desired copolymer is recovered by complete removal of the toluene by vacuum distillation.

Aspect No. 2: The polyimination reaction is carried out in bulk using instrument No. 2. 0.01 mol of diamine compound M (reactant
(3)) and 0.01 mol of the siloxane precursor monomer In is charged to the reactor. Switch on the stirrer and heat the reactants to an average temperature of 150 ° C. Stirring and heating were continued under atmospheric pressure for 2 hours, then a vacuum of 1 Pa was progressively achieved, and the reaction was continued under these conditions for a further 10 hours.

3. Results of Examples 4-7 The polymers produced are generally in the form of orange colored solid products.

In Table 1 below, the amounts of reactants and products and various parameters given by steric exclusion chromatography are reported for each copolymer prepared.

In Table 2 below, the value of the phase transition temperature measured by DSC and the nature of the existing phase observed using a polarization microscope are reported for each copolymer prepared.

Claims (11)

[Claims] 1. A formula: [In the formula, the symbols A are the same, and each is a single bond or -O-, And the symbol D is a group of the following formula: (In the formula, y is an integer in the range of 0 to 2, and the symbol E is a single bond or -CH = N-, -N = CH when y = 1.
-, Or And when y = 2, a single bond, Or In which R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are the same or different and are monovalent selected from linear or branched alkyl groups containing 1 to 12 carbon atoms. A hydrocarbon group which can be substituted by at least one chlorine, bromine or fluorine atom or by a -CN group; or at least one alkyl and / or alkoxy group containing 1 to 4 carbon atoms or at least A phenyl group optionally substituted by one chlorine atom, the symbol X being an integer ranging from 2 to 8 and the symbol n
Is a whole number or fraction in the range of 0 to 50], and a method for producing an essentially linear thermotropic copolymer containing in the structure repeating units, comprising steps (c) and (d): ) Under anhydrous conditions, operating under an inert atmosphere containing no oxygen at a temperature not exceeding 80 ° C. and in the presence of a hydrosilylation catalyst, (1) α, ω-bis (hydro) of the following formula: Diorganopolysiloxane; (Wherein R _{1 to} R ₆ and n have the meanings given above), and (2) a bifunctional compound of the following formula: Where the symbols x and A have the meanings given above, and then from the reaction mixture: And / or immediately after the CH ₂ ═CH-functional group has completely disappeared, by separating the siloxane precursor monomer immediately below, each α, ω-disubstituted by a group containing a p-formylphenyl residue. Diorganopolysiloxane species of the formula; By synthesizing a siloxane precursor monomer containing in the structure, and (d) a method known per se, (3) an aromatic diamine compound of the following formula: H ₂ N-D-NH ₂ (IV) (formula (Wherein the symbol D has the above meaning) and (4) the siloxane precursor monomer obtained at the end of the step (c) is reacted, and then the aldehyde and / or NH ₂ -functional group is completely eliminated. Immediately after which the polyimination reaction is carried out continuously by synthesizing the desired thermotropic copolymer by separating the desired thermotropic copolymer from the reaction mixture by a method known per se. And the above method. 2. The process of claim 1 wherein the first step (c) is carried out in a homogeneous medium by adding to the starting reactants a solvent or solvent mixture common to the reactants and the desired product. 3. The method according to claim 1, wherein the first step (c) is carried out at a temperature in the range of 20 ° C. to 80 ° C. 4. A bifunctional reactant (2) 4. The process according to any one of claims 1 to 3, which is used in an amount equal to 2 mol per mol of the reactant (1) containing. 5. In carrying out the first step (c), first the reactor with the reactant (2) is charged and then the catalyst is added, after which the bis- (hydro) siloxane reactant (1) is stirred. And gradually introducing into the heated and heated reactants.
4. The method according to any one of 4 to 4. 6. The process according to claim 1, wherein the second step (d) is carried out in bulk by heating the reactants under atmospheric pressure and then optionally under reduced pressure. 7. The second step of (d), the weight of the reactants and the concentration of the solvent 100 cm ³ per reactant embodiment was and the reaction in the presence of a common solvent or solvent mixture to the desired copolymer g
6. The method of any one of claims 1 to 5, wherein the method is represented as at least 5%. 8. The method according to claim 6, wherein the second step (d) is carried out at a temperature in the range of 50 ° C. to 200 ° C. 9. A process according to any one of claims 6 to 8 wherein the diamine reactant (3) is used in an amount equal to 1 mole per mole of siloxane precursor monomer reactant (4). 10. The method of any one of claims 6 to 9, wherein in the second step (d), the polyimination reaction is carried out by azeotropic distillation while continuously and slowly removing water for polyimination. Method. 11. A novel industrial product which can be used particularly when the method according to any one of claims 1 to 10 is used, wherein α and ω are each a group containing a p-formphenyl residue.
A disubstituted diorganopolysiloxane of the formula: (Wherein the symbols A, x, R _{1 to} R ₆ and n have the same meanings as described above in relation to the formula (VI)) in the structure.