FR2512824A1 - Organo silicon polymer - is prepd. by adding anhydrous metal halide to poly:silane and heating - Google Patents

Abstract

Organo silicon polymer has a main chain skeleton mainly comprising units of formulae (A), (B), (C), (D), (E) and (F) (where R is CH3 or W) which form chain, branch and cyclic structures. The main chain skeleton contains a polysilane skeleton of (Si)n (where n is 2-10). The organo silicon polymer exhibits absorption in the far infrared region of 450-300 cm power minus 1 in the IR spectra and absorption at 340-370 nm in the UV spectra, and has a number average mol. wt. of 400-5,000. Prepn. comprises adding 0.5-10 wt.% of one or more anhydrous halogenated metals, pref. chlorides and bromides of Gps. II, III, IV (except carbon), Vb, VIb, VIIb and VIII metals, Sb and Bi to a polysilane having a structure.

Description

 The present invention relates to novel organosilicon polymers composed primarily of a carbosilane skeleton and a polysilane backbone, and its preparation.

Polymers whose skeleton is composed of alternating silicon and carbon atoms, an organic group forming a side chain being bonded to a silicon atom, are called polycarbosilanes. Since these polymers are converted to silicon carbide-containing inorganic materials as the main constituent when burned in a non-oxidizing atmosphere, they are suitable as raw materials for the preparation of silicon carbide, and are used in the form of carbide fibers. silicon, sintering aids, impregnating agents, fine powders of silicon carbide etc.
The polycarbosilanes known hitherto include for example that described by Fritz: Angew.

Chem., 79, p. 657 (1967), which is synthetically prepared by thermally decomposing and condensing a monosilane at a temperature of 600 to 8000C in a flow-type reactor, and that described in U.S. No. 4,052,430 issued to Yajima et al. A polycarbosilane having a siloxane linkage can be synthesized by the method described in US Pat. No. 4,220,600, issued to Yajima et al., Which comprises adding a polyborosiloxane having a phenyl group at least partially in a side channel of Si, as an activating agent of the reaction, to a polyorganosilane, and to decompose and thermally condense at a temperature of 250 to 5000C under atmospheric pressure.

These synthetic processes, however, are not industrially advantageous because they require high temperatures and a flow-type device for recycling, or high pressures in a pressure vessel. In addition, when a special reaction activating agent such as a polyborosiloxane is used, the resulting polymer contains a siloxane bond and therefore is unsuitable when it is desired to minimize oxygen in the clogged product. .

 Since these conventional polycarbosilanes can be converted into silicon carbide by combustion in a non-oxidizing atmosphere, they are very useful as raw materials for the preparation of thermally stabilized mineral materials. In addition, since they are soluble in ordinary organic solvents and thermoplastics, they can be converted into molded articles of various shapes. In order to burn these molded articles in their molding forms, they must first be rendered infusible by cooking. For cooking, the best method is to heat the molded articles in the air. For this purpose, it is necessary to heat them gradually to a temperature close to the softening point of the polycarbosilane, or to heat them for a very long time at low temperature. The ordinary polycarbosilanes have the defect that molded articles melt during cooking or cooking is not completely finished and does not touch the interior of the molded articles.

 It is extremely difficult to eliminate these defects.

 The Applicant has carried out extensive studies to eliminate the above defects. These studies led to the discovery of a process for the preparation of a novel organic silicon polymer mainly composed of a carbosilane skeleton and a polysilane backbone, which does not require the use of a special device such as the flow-type device designed for recycling or a pressure vessel, or a special reaction-initiating agent such as a polyborosiloxane. The Applicant has also found that the organic silicon polymer obtained by the above process, which consists mainly of a carbosilane skeleton and a polysilane backbone, can be insolubilized more easily than the polycarbosilanes obtained by ordinary methods, and has a high high residual ratio in combustion in atmosphere.

dans laquelle n est au moins égal à 3, la quantité d'halogénure métallique étant de 0,5 à 10% en poids par rapport au poids du polysilane, et à chauffer le mélange en atmosphère inerte vis-à-vis de la réaction.The invention relates to a process for preparing an organosilicon polymer having a carbosilane backbone and a polysilane backbone, which comprises adding at least one anhydrous metal halide to a polysilane having the following formula

in which n is at least 3, the amount of metal halide being 0.5 to 10% by weight relative to the weight of the polysilane, and heating the mixture in an inert atmosphere vis-à-vis the reaction.

dans lesquels R représente CH3 ou H,
Ces motifs formant des structures linéaires, ramifiées et cycliques et le squelette de la channe principale de ce polymère étant un polysilane répondant à la formule

dans laquelle n est un nombre de 2 à 10. The organosilicon polymer of the invention obtained by the above process consists mainly of the following (A), (B), (C), (D), (E) and (F) units.

in which R represents CH3 or H,
These patterns forming linear, branched and cyclic structures and the skeleton of the principal channe of this polymer being a polysilane corresponding to the formula

in which n is a number from 2 to 10.

 The organosilicon polymer of the invention usually has a far-infrared absorption of -1450 to 300 cm, an absorption limit appearing at 340370 nm in the absorption spectrum W, and a number average molecular weight. from 400 to 5000.

 Figure 1 is an IR absorption spectrum (KBr tablet method) of the organosilicon polymer synthesized by adding 1.50 g of AlCl in Example 1 of the present invention.

Figure 2 is a far infrared absorption spectrum (KI tablet process) of the same organosilicon polymer as in Figure 1; and
Figure 3 is an absorption spectrum W of the same organosilicon polymer as in Figure 1.

 The method of the invention will first be described.

A starting material used in the process of the invention is a polysilane of the formula

It can be linear or cyclic or have a linear - cyclic mixed structure. Linear polysilane (10 # n) is preferred and the terminal group is preferably
OH or CH3. It is also possible to use polysilanes in which the methyl groups are partially replaced by ethyl groups, phenyl groups or by hydrogen. But the use of these polysilanes can lower the product yield, and the polysilanes in which the methyl groups are partially replaced by hydrogen are unstable and flammable.

The polysilanes used in the invention can be synthesized by various methods, for example those described in a Japanese language publication nSynthetic
Reactions Using Organometallic Compounds (Part II) "by
Takeo Saegusa, Yoshihiko Ito and Makoto Kumada, or K. Kumada and
K. Tamao, Advan. Organometal. Chem., 6, 19 tliS}
The linear polysilane is synthesized using the condensation reaction of a methylhalosilane with an alkali metal such as potassium, sodium, a sodium-potassium alloy or lithium.

The other starting material used in the process of the invention is the anhydrous metal halide which may be at least one halide of a Group II metal (alkaline earth metals or zinc group metals), III, IV with the exception of carbon, VIII (iron group), V, VIb or
VIIb of the Periodic Table, antimony or bismuth
The halide may be a fluoride, a chloride, a bromide or an iodide. Chloride and bromide and in particular chloride are preferred. It is preferred to use the anhydrous metal halide. If a hydrated metal halide is used, the reaction may not take place, or oxygen is present in the backbone of the organosilicon polymer formed. As examples of suitable metal halides that can be used, will quote: BeCl2, SrCl2, NdC13,
ThCl4, TiCl4, ZrCl4, HfCl4, VCl3, VCl4, NbCl5, TaCl5, CrCl3,
MnCl2, Fc13, CoCl2, ZnCl2, AlCl3, GaCl3, TlCl, SiCl4,
GeCl4, SnCl41 PbCl2, SbCl5, SbCl3, BiCl3, AlBr3 and GaBr3.

Of these, AlCl3, GaCl3, MnCl2, ZrCl4,
TiCl4, VC13 and CrCl3 are particularly suitable because they increase the molecular weight of the product formed. The reaction of the invention can be carried out using a mixture of at least one of these chlorides and another chloride, in the presence, if desired, of a small amount of a hydrohalic acid.

In this case, the molecular weight distribution of the organosilicon polymer is easily achieved.

(n > 3) et on chauffe le mélange dans une atmosphère inerte vis-àvis de la réaction.In the process of the invention, 0.5 to 10% by weight, based on the weight of the polysilane, of at least one metal halide, is added to the polysilane corresponding to the formula

(n> 3) and the mixture is heated in an inert atmosphere with respect to the reaction.

 An important advantage of the process of the invention is that it does not require to react the mixture of a special reactor such as a pressure reactor or a flow-type system designed for recycling; the reactor used in the process of the invention may be a reactor, for example a canister-type stainless steel reactor, equipped with an inlet port and an outlet port for a gas inert with respect to of the reaction and a reflux system capable of cooling and refluxing low boiling components during the reaction when the reactor is heated by an oven such as an electric furnace.Another advantage is that no special reaction activating agent is required, and that easy to obtain anhydrous metal halides can be used.

 It is essential in the process of the invention that the reaction be carried out in a gas atmosphere inert to the reaction. If the reaction is carried out in an oxidizing atmosphere such as air, the starting polysilane can oxidize. Examples of inert gases include nitrogen, argon, helium, carbon monoxide, carbon dioxide, hydrogen and hydrocarbons.

 In general, the reaction is preferably carried out at atmospheric pressure. If operated under vacuum or reduced pressure, the low molecular weight components escape by distillation from the reaction system, and the yield of the final product decreases markedly. When the process of the invention is applied, the reaction is preferably carried out by sending a stream of an inert gas into the reaction zone, because by operating in this way, the pressure inside the reactor is maintained equal to atmospheric pressure, and it avoids an increase in temperature or an increase in pressure due to the gases such as hydrogen and methane formed during the reaction.

 The heating temperature used in the process of the invention is lower than in the prior art, and one of the other advantages of the process is that it can usually be operated at 2500 ° C or higher, preferably at room temperature. a temperature of 280 to 400 C.

If the reaction temperature is less than 2500 ° C., the reaction does not progress sufficiently, and at 45 ° C. or more, undesired gelation of the resulting organosilicon polymer occurs.

 In the process of the invention, the reaction time is usually at least 3 hours. When the reaction is carried out for more than 20 hours, no substantial improvement in the organosilicon polymer obtained is generally achieved, although this depends on the type of metal halide used.

 In the process of the invention, the proportion of the anhydrous metal halide is 0.5 to 10% by weight relative to the weight of the polysilane. These limits have been set because if the amount of halide is less than 0.5% by weight, the proportion of the polysilane backbone in the organosilicon polymer obtained is very high relative to the proportion of carbosilane backbone.

As a result, the polymer may become insoluble in ordinary organic solvents, or have a very low residual ratio by combustion in a non-oxidizing atmosphere. On the other hand, if the metal halide is added in a proportion greater than 10% by weight, the product will be gelled. In addition, the use of an anhydrous metal halide not causing gelling of the polymer even when added in a proportion greater than 10% by weight is economically disadvantageous in the production of the organosilicon polymer of the invention. In this case, the use of a mixture of at least two anhydrous metal halides is possible. The preferred proportion of the anhydrous metal halide is from 1.0 to 80 weight percent.

 The organosilicon polymer obtained by the above reaction can be purified by dissolving in a solvent, filtering the solution, hot if necessary, and then removing the solvent by evaporation. If desired, the average molecular weight of the polymer can be increased by removing low molecular weight components at a temperature of 50 to 45 ° C., at atmospheric pressure or under reduced pressure. Examples of suitable solvents are n-hexane, cyclohexane, benzene, toluene, xylene and tetrahydrofuran. Another method for increasing the average molecular weight of the polymer involves selectively precipitating high molecular weight components using a mixture of the above good solvent and a poor solvent such as acetone, methanol or the like. ethanol.

 The novel feature of the process of the invention is that an organosilicon polymer composed mainly of a carbosilane backbone and a polysilane backbone is produced from a mixture of a polysilane and a small amount of anhydrous metal halide.

This feature is considered to have the advantage of not requiring any special reactor and special reaction activating agent and to use relatively low heating temperatures. The mechanism for obtaining this advantage by adding a small proportion of the anhydrous metal halide to the polysilane will be described below. But it is a simple theoretical explanation, in no way limiting the invention.

The polysilane, one of the starting materials used in the invention, gradually decomposes at a heating temperature which is generally at least about 1800C in a non-oxidizing atmosphere. At a temperature above 2800C, most of the polysilane is converted into a monosilane mixture

<tb><SEP> of <SEP> -Si, <SEP> of <SEP> poly
<tb><SEP> t <SEP> I
<tb>Si;<SEP> (2n <SEP>>;<SEP> O)
low molecular weight silane, low molecular weight polysilane and partially converted to carbosilane, and thermal decomposition terminates at about 4000C. These low molecular weight products tend to be released from the reaction system. To perform the polymerization reaction in good yield, the dispersion of the low molecular weight products is avoided in accordance with the prior art, using a special device such as a pressure vessel or flow-type device for recycling low molecular weight constituents in a heated portion at high temperature to progressively increase their molecular weight, or a special reaction activating agent, such as a polyborosiloxane, capable of forming an intermediate product with these low molecular weight components through a siloxane bond and capturing them.

 In contrast, when a mixture of polysiloxane and anhydrous metal halide is used as the starting material in accordance with the process of the invention, the low molecular weight products are converted into an organosilicon polymer composed of a carbosilane backbone and of a polysilane skeleton with a good yield. The mechanism of the transformation can not be deduced in a simple way from the fact that metal halides such as aluminum chloride are used as catalysts in Friedel-Crafts reactions in the broad sense, that is to say alkylation, synthesis ketones, synthesis of carboxylic acids, synthesis of aldehydes, halogenation, isomerization, polymerization, etc. But we can make the following theoretical considerations.

The polysilane used in the invention begins to decompose gradually at a temperature of more than about 1800C to give low molecular weight constituents. This is mainly due to the radical cleavage of the Si-Si bond, the radicals obtained extracting hydrogen from the methyl groups of the polysilane.

Sometimes methyl groups whose hydrogens have been extracted can form a carbo bond
II silane corresponding to the formula -Si - C - Si- by a reaction
II radical transfer represented by the following formula:

 However, since many radicals are formed in the reaction system, recombination of the radicals occurs primarily by giving a monosilane, a polysilane, or low molecular weight products such as partially polysilane carbosilane, which are stable.

If a metal halide is present during thermal decomposition, halogenation of the methyl groups of the polysilane occurs. Although the mechanism of this reaction has not been fully elucidated, it can be assumed that it is due to the presence of traces of hydrogen halide, as shown in the following diagram

The polysilane bearing halogenated methyl groups easily forms a carbosilane linkage in the presence of a catalytic amount of the metal halide graciated with an intramolecular rearrangement represented by the following scheme

 The halogen atoms that have moved to the silicon atoms are extracted by the hydrogens present in the reaction system and the hydrohalic acid is regenerated, so that the halogenation of the methyl groups takes place again. In this way, the polysilane used in the invention is converted into a polymer containing many carbosilane backbones that are not sensitive to heat decomposition, before being decomposed into a stable, low molecular weight product. The catalytic action of the metal halide on the polysilane is also exerted on the intramolecular rearrangement of the linear polysilane to branched polysilane, or on a ring reduction reaction of the cyclic polysilane. Since these reactions generally take place in the direction of the formation of the isomer which has the highest degree of branching and which is the most thermally stable, the organosilicon polymer synthesized by the process of the invention is composed of a carbosilane skeleton and a polysilane backbone.

The organosilicon polymer obtained by the process of the invention has the following characteristics:
The IR spectrum of the organosilicon polymer of the invention has absorptions attributable to
Si-CH 3 at about 830 cm -1 and 1250 cm -1 CH at 141 O, 2900 and 2950 cm -1 Si-H at 2100 cm -1 and Si-CH 2 Si at 1030 and 1355 cm -1, as shown in Figure 1. It also shows a wide range of Absorption ranging from 300 to 450 cm -1, as shown by the infrared absorption spectrum in the region 600 to 250 cm 1 of Figure 2. This absorption originates from an Si-Si bond and has a peak of absorption at 400 cm -1 for (Me 2 Si) 5, 383 cm -1 for (Me 2 Si) 6 and 362 cm -1
for (Me2Si) 7, it is therefore inherent to the cyclic polysilane.

Obviously, the linear polysilane used in the invention has no absorption in the far-infrared region. It has therefore been found that the organosilicon polymer obtained in the invention contains in its backbone a polysilane moiety, such as a 5-, 6- or 7-membered ring.

 FIG. 3 represents an absorption spectrum W of the polymer of the invention. In this spectrum, the absorption limits are at 340-370 nm, and strong absorption exists in the ultraviolet region.

 For comparison, the polysilane used in the invention is reacted in an autoclave at 470 C for 14 hours under a final pressure of 110 kg / cm 2 to produce a polycarbosilane having a number average molecular weight of 1800. absorption of this polycarbosilane is represented by a broken line.

TABLE I
Maximum UV absorption compound
max (nm) &gamma; max (cm-1)
Me3SiSiMe3 193.5 51700
Me (Me2Si) 3Me 216.3 46200
Me (Me2Si) 4Me 235.0 42550
Me (Me2Si) 5Me 250.0 40000 220.0 (sh.)
Me (Me2Si) 6Me 38500
260.0
215.0 (sh.)
Me (Me2Si) 8Me {240.5 36700 272.5
261 38300
(Me 2 Si) 5
272 36700
232 43100 (Me2Si) 6
255 39200
217 46100 217 46100 (Me2 Si) 7
242 41300
sh: shoulder
In many cases, the polysilane has an absorption maximum in the ultraviolet portion, as shown in Table I. The absorption spectrum of FIG. 3 shows that the backbone of the obtained organosilicon polymer contains a linear polysilane portion and / or cyclic
(Si) n (2 # n # 10).

The 1 H NMR and 13 C NMR spectra of the polymer of the invention were also established using tetramethylsilane as a standard substance. The 1 H NMR spectrum shows an absorption peak at 4-5.5 ppm attributable to Si-H, a broad absorption peak attributable to a mixture of SiMe,
SiMe, Si-CH2- and

The 13C NMR spectrum shows only a broad absorption peak at -7 to 20 ppm, and this confirms that SiMe 2, Si-CH 2 -, Si-CH-, and the like are mixed.

The relative proportions of the elements determined by chemical analysis are usually 40 to 55% Si, 30 to 40% C, 0.1 to 3.5% O, and 6.5 to 8.5% Si.
H, based on the weight of the polymer. The proportion of metal element in the polymer attributable to the metal halide is not greater than 0.1% by weight, and usually 0.05% by weight.

 From the results of the above IR, W and NMR spectra and chemical analysis, the following conclusions can be drawn about the structure of the organosilicon polymer of the invention.

The IR spectrum indicates that the elements constituting the organosilicon polymer are as follows

The far-infrared absorption spectrum shows that the polymer has cyclic polysilane moieties such as

 The absorption spectrum W shows that the polymer has a linear polysilane part corresponding to the formula (Si) n (2 # n # 10) in addition to the cyclic polysilane parts.

The 1 H NMR and 13 C NMR spectra show that the polymer has the following

There may also be constituent elements formed of the carbosilane backbone and the polysilane backbone, such as

As a result, the organosilicon polymer of the invention consists to a large extent of the following units (A), (B), (C), (D), (E) and (F).

(R = CH3 or H)
These structural units form linear, branched or cyclic structures, and the main chain of the polymer also has the polysilane backbone -Si (2cnC 10). For example, it can be supposed that the polymer of the invention has the following molecular structure :
see diagram next page

 The organosilicon polymer of the invention has a number average molecular weight, measured by the vapor pressure osmosis method, of 400 to 5000.

 Because it has a polysilane backbone, the organosilicon polymer of the invention is easier to render infusible than the polycarbosilanes prepared by ordinary methods. When heated to low temperature, the polysilane backbone reacts readily with oxygen forming a siloxane bond. It is also very easy to form radicals under the action of ultraviolet rays. As a result, cross-linking occurs and the polymer becomes infusible.

 This is clear from the results in Table II below, which were obtained by comparing (1) an organosilicon polymer of the invention obtained by adding 1.5 g of anhydrous aluminum chloride to 100 g of polysilane. and heating the mixture at 3550C for 16.5 hours, (2) a polycarbosilane obtained by an ordinary method by reacting a polysilane in an autoclave at 470 C for 14 hours under a final pressure of 110 kg / cm 2, and (3) a polycarbosilane containing a siloxane linkage, obtained by an ordinary method by adding 3.2% by weight of polyborodiphenylsiloxane to the polysilane, and reacting them at 350 ° C for 6 hours.

TABLE II

Polycarboailane <SEP> Pre- <SEP> Polycarbosilane <SEP> Con <SEP> Polymer <SEP> Organoparate <SEP> by <SEP> the <SEP> prooede <SEP> holding <SEP> a <SEP> binding <SEP> silicon <SEP> from <SEP> the inordinaire <SEP> under <SEP> pras <SEP> siloxane <SEP> prepared <SEP> by <SEP> vention
<tb><SEP><SEP> ordinary <SEP> process
<tb> Mass <SEP> molecular <SEP> average
<tb> in <SEP> number <SEP> 1750 <SEP> 1860 <SEP> 1600
<tb> Temperature <SEP> of <SEP> start <SEP> of
<tb> oxidation <SEP> (C) <SEP> when <SEP> 180 <SEP> 110 <SEP> 80
<tb> that <SEP> heats <SEP> to <SEP> 5 C / min.
<Tb>

in <SEP> the air
<tb><SEP> fraction insoluble <SEP> in
<tb><SEP> cyclohexane <SEP> (%) <SEP> 20 <SEP> h
<tb> after <SEP> irradiation <SEP> with <SEP> of <SEP><1<SEP> 15 <SEP> 65
<tb> the <SEP> light <SEP> UV <SEP> to <SEP> 254 <SEP> nm
<tb> Residual <SEP> Report <SEP> (%)
<tb> after <SEP> combustion <SEP> in <SEP> now <SEP> the <SEP> polymer, <SEP> subject
<tb> to <SEP> iradiation <SEP> UV <SEP> ci- <SEP> 55.3 <SEP> 62.5 <SEP> 79.8
<tb> above. <SEP> to <SEP> a <SEP> heating <SEP> in
<tb> argon <SEP> during <SEP> 1 <SEP> h. <SEP> to
<tb> 1300 C
<Tb>
As shown in Table II, the organosilicon polymer of the invention has the advantage of having a high residual ratio to combustion, and of being easy to convert into molded articles of various shapes. The organosilicon of the invention may be obtained in various forms ranging from a viscous liquid at room temperature to a thermoplastic solid melting at 3000 ° C. and is soluble in various solvents such as n-hexane, cyclohexane, benzene, toluene, xylene and tetrahydrofuran. .

 As a result, it can be transformed into molded articles of various shapes. It is advantageous to render the organosilicon polymer infusible and heat it to a temperature of at least 8000 in non-oxidizing atmospheres, thereby transforming it into a molded article composed mainly of SiC while retaining its shape.

Examples of such molded articles include continuous fibers, films and silicon carbide coatings.

 The following nonlimiting examples are given by way of illustration of the invention.

EXAMPLE 1
In a 3-necked flask, 2.5 liters of anhydrous xylene and 400 g of sodium are introduced and heated in a stream of nitrogen to the boiling point of xylene. With stirring, 1 liter of dimethyldichlorosiloxane is added dropwise over 45 minutes. After the addition, the mixture is refluxed for 10 hours to form a precipitate. The precipitate is filtered, washed with methanol and then with water, dried and further washed with acetone and benzene, yielding 380 g of a polysilane of formula.

 (n) 10) in the form of a white powder.

 AlCl3 is added at a rate of 1.00, 1.25, 1.50 or 1.60 g to 100 g of the polysilane obtained. The mixture is heated for 8 hours or 16.5 hours in a stream of nitrogen in a 10 liter quartz tube equipped with a reflux tube. After the reaction, the reaction mixture is dissolved in xylene and filtered to remove impurities.

The filtrate is distilled in a nitrogen atmosphere by heating at 3200C to remove xylene and low-boiling components, thereby forming an organosilicon polymer according to the invention. The results are given in Table III. The reaction temperatures below are all the final reaction temperatures.

TABLE III

Quantity <SEP> of <SEP> Temperature <SEP> Time <SEP> of <SEP> Yield <SEP> Mass <SEP> mo
<tb> AlCl3 <SEP> Added <SEP> of <SEP> reaction <SEP> reaction <SEP> lecular
<tb> @@@@@@@@
<tb><SEP> (g) <SEP> (C) <SEP><SEP> (hours) <SEP> (g) <SEP> mean
<tb><SEP> (s) <SEP> Notbre
<tb><SEP> 1.00 <SEP> 330 <SEP> 8.0 <SEP> 58.0 <SEP> 650
<tb><SEP> 1.00 <SEP> 335 <SEP> 16.5 <SEP> 62.0 <SEP> | <SEP> 1000
<tb><SEP> 1.25 <SEP> 340 <SEP> 16.5 <SEP> 66.0 <SEP> 1270
<tb><SEP> 1.50 <SEP> 355 <SEP> 16.5 <SEP> | <SEP> 59.5 <SEP> 1600
<tb><SEP> 1.60 <SEP> 370 <SEP> 8.0 <SEP> 50.5 <SEQ> 4100
<Tb>
EXAMPLE 2
Anhydrous zirconium chloride, ZrCl4, is added at 1.96, 2.50, 3.00 or 5.00 g to 100 g of the polysilane synthesized in Example 1, and the mixture is reacted for 16.5 hours in the same manner as in Example 1, this mistletoe gives an organosilicon polymer of the invention. The results are given in Table IV.

TABLE IV

<SEP> Quantity <SEP> of <SEP> Temperature <SEP> Yield <SEP> Mass <SEP> mo- <SEP>
<tb><SEP> ZrCl4 <SEP> Added <SEP> of <SEP> reaction <SEP> lecular
<tb> average
<tb><SEP> (g) <SEP> (C) <SEP> (g)
<tb><SEP> in <SEP> number
<tb><SEP> 1.96 <SEP> 340 <SEP> 67.0 <SE> 570
<tb><SEP> 2.50 <SEP> 350 <SEP> 56.5 <SEP> 1100
<tb><SEP> 3.00 <SEP> 355 <SEP> 56.0 <SEP> 1260
<tb><SEP> 5.00 <SEP> 370 <SEP> 55.5 <SEP> 3900
<Tb>
EXAMPLE 3
MnCl 2, CrCl 3, VCl 3, TiCl 4 or GaCl 3 are added to 100 g of the polysilane prepared by synthesis in Example 1, and the mixture is reacted for 16.5 hours in the same manner as in Example 1, for obtain an organosilicon polymer of the invention. The results are given in Table V.

TABLE V

<tb> Halide <SEP> Quantity <SEP> Tompater <SEP> Yield <SEP> Mass <SEP> Molecule
<tb> metal <SEP> (g) <SEP> of <SEP> reaction <SEP> (g) <SEP> mean <SEP> average
<tb><SEP> (C) <SEP> in <SEP> number
<tb><SEP> MnCl2 <SEP> 5.00 <SEP> 365 <SEP> 58.0 <SEP> 1800
<tb><SEP> CrCl3 <SEP> 5.00 <SEP> 350 <SEP> 62.0 <SEP> 1150
<tb><SEP> VCl3 <SEP> 5.00 <SEP> 370 <SEP> 55.4 <SEP> 2850
<tb><SEP> TiCl4 <SEP> 2.50 <SEP> 340 <SEP> 68.3 <SEP> 960
<tb><SEP> TiCl4 <SEP> 3.00 <SEP> 355 <SEP> 70.0 <SEP> 1100
<tb><SEP> TiCl4 <SEP> 5.00 <SEP> 368 <SEP> 58.0 <SEP> 1710
<tb><SEP> GaCl3 <SEP> 3.00 <SEP> 360 <SEP> 58.5 <SEP> 2050
<tb> EMPLE 4
CoCl2, pbCl2, BiCl3, ZnCl2, SiCl4,
TlCl ;; TaC15, FeC13, SnCl4 or SrC12 at 100 g of the polysilane prepared by synthesis in Example 1, and the mixture is reacted for 16.5 hours in the same manner as in Example 1, to obtain a polymer organosilicon according to the invention.

The results are given in Table VI.

TABLE VI

<tb> Halide <SEP> Quantity <SEP> Temperature <SEP> Yield <SEP> Mass <SEP> Molecule
<tb> metallic <SEP> | <SEP> (g) <SEP> | <SEP> of <SEP> reaction <SEP> (g) <SEP> mean <SEP> average
<tb><SEP> (C) <SEP> in <SEP> number
<tb> Cocl2 <SEP> 3.00 <SEP> 290 <SEP> 75.0 <SEP> 450
<tb> PhCl2 <SEP> 3.50 <SEP> 310 <SEP> 72.0 <SEP> 600
<tb> BiC13 <SEP> 6.00 <SEP> 300 <SEP> 74.0 <SEP> 580
<tb> ZnCl2 <SEP> 5.00 <SEP> 330 <SEP> 48.0 <SEP> 500
<tb> SiCl4 <SEP> 3.00 <SEP> 345 <SEP> 67.0 <SEP> 740
<tb> TlCl <SEP> 5.00 <SEP> 308 <SEP> 74.0 <SEP> 660
<tb> TaC15 <SEP> 5.00 <SEP> 350 <SEP> 60.0 <SEP> 820
<tb> FeCl3 <SEP> 5.00 <SEP> 320 <SEP> 70.0 <SEP> 670
<tb> SnCl4 <SEP> 5.00 <SEP> 320 <SEP> 73.5 <SEP> 580
<tb> SrCl2 <SEP> 5.00 <SEP> 300 <SEP> 73.0 <SEP> 550
<Tb>
EXAMPLE 5
3.00 g of CoCl 2 PbCl 2 or SiC 14 and 1.00 g of AlCl 3 are added to 100 g of the polysilane prepared by synthesis in Example 1, and the mixture is reacted for 8 hours in the same manner as in Example 1, to obtain an organosilicon polymer of the invention. The results are given in Table VII.

TABLE VII

<tb><SEP> Halide <SEP> Temperature <SEP> Yield <SEP> Mass <SEP> Molecule
<tb><SEP> metal <SEP> of <SEP> reaction <SEP> mean <SEP> average
<tb><SEP> (C) <SEP> (g) <SEP> in <SEP> number
<tb> CoCl2 <SEP> + <SEP> AlCl3 <SEP> 340 <SEP> 74.0 <SEP> 950
<tb> PbCl2 <SEP> + <SEP> AlCl3 <SEP> 345 <SEP> 69.8 <SEP> 1110
<tb> SiCl2 <SEP> + <SEP> AlCl3 <SEP> 360 <SEP> 65.0 <SEP> 1270
<Tb>
Comparison of the results obtained in this example with those of Example 1 shows that when the number-average molecular weight of the organosilicon polymer is to be progressively modified, it is advantageous to use these mixed halides.

Claims (6)

 1. Organosilicon polymer, characterized in that the skeleton of the main channe is composed mainly of the following patterns (A), (B), (C), (D), (E) and (F):

 where R represents CH3 or H, these structural units forming linear, branched and cyclic structures, and this skeleton of the principal channe further having a polysilane backbone

 (2 # n # 10).  2. Organosilicon polymer according to claim 1, characterized in that it has an absorption of 450 to 300 cm 1 in the far infrared region of the IR absorption spectrum, an absorption limit at 340-370 nm in the spectrum W, and a number average molecular weight of 400 to 5000.  3. A process for preparing an organosilicon polymer according to claim 1, characterized in that one or more anhydrous metal halides are added to a polysilane corresponding to the formula

 the amount of metal halide being from 0.5 to 10% by weight relative to the polysilane, and the mixture is heated in an inert atmosphere with respect to the reaction.  4. A process according to claim 3, characterized in that the metal halide is at least one compound selected from the group II metal halides (alkaline earth metals and zinc group metals), III, IV (to except for carbon), VIII (iron group metals), Vb, VIb and VIIb, antimony halides and bismuth halide.  5. Process according to claim 4, characterized in that the metal halide is chosen from BeCl2 SrCl2, NdCl3, ThCl4, TiCl4, ZrCl4, HfCl4, VCl3, VCl4, NbCl5, TaCl5, CrCl3, MnCl2, FeCl3, Cocl2, ZnCl2, AlCl3, GaCl3, TlCl, SiCl4, GeCl4, SnCl4, PbCl2, SbCl5, SbCl3, BiCl3, AlBr3 and GaBr3.  6. A process according to claim 3, characterized in that the heating temperature is between 250 and 4500C.