BE466878A - - Google Patents

Description

       

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  ORGANO-SILICIC POLYMERS OF CHARACTER. RESINOUS AND THEIR APPLICATIONS.



     The invention which will be described below relates to polymerized organo-silicic compounds of resin character and in which the silicon atoms are found isolated from each other in the resin molecule, by other atoms or groups. atoms devoid of silicon. To make it clearer, the invention will first be explained in the case of polymers of methylsilicones. A method of preparing polymerized silicones by dehydration of silicols will then be described. Finally, we will indicate a generalization.



   Until now, methylsilicone could not be prepared. As a result of the invention, it is possible to obtain stable polymers from them, the properties of which make them usable industrially. In the polymers of

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 dimethylsilicone Intervenes the t link
 EMI2.1
 the repetition of which provides High molecular weight materials. The ends of the chain have different constitutions mentioned later.



   In other compositions, certain methyl groups can be replaced by as many oxygen atoms according to the constitution:
 EMI2.2
 links having one and / or the other of these structures can be associated in a single polymer molecule and thus vary the properties of the substances obtained.



   The polymers of methylsilieones are remarkable in that there is no direct bond between carbon atoms. Such polymers are therefore free from the properties which are observed during thermal decomposition when the latter breaks a carbon-carbon bond, in particular the silicones studied by Kippong and his collaborators and described in the "Journal of the Chemical Society" T.95, p.302- t.101. p.2108, 2121, 2125, 2142, 2156-T.107, pt459- T.123. p, 2830, all contained an ethyl, propyl, phenyl, benzyl or tolyl group. All of these silicones have at least one intercarbon bond in their structure.



   For the preparation of polymers of methylsilicones, one can hydrolyze a silicon-methyl halide, for example the chloride, bromide or iodide, and dehydrate the resulting hydroxylated product. Preferably, silicon-methyl chloride is used.



    EXEMPTED f- (A) A 1.75 month ethereal solution of bromide is added slowly. of methylmagnesium, with rapid stirring, to an ethereal solution of one mol of silicon tetrachloride, the initial temperature being less than or equal to -20 C. The addition of solution of the methylagnesium bromide is made in such a way that the temperature of the mixture does not rise above 0 ° C. If necessary, it is cooled. It is preferable that the reaction be carried out at -20 C ov lower.



   Since there is insufficient magnesium bromide to convert all of the silicon tetrachloride to a dimethyl derivative, a mixture of mono chloride and dimethyl silicon is obtained:

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 EMI3.1
 
A lower proportion of trimethylsilicon chloride is probably also formed
CH3MgBr + (CH3) 2SiC12 - (CH3) SiC1 + moral The magnesium salts are separated in the form of a granular mass, leaving the silicon derivatives in solution in ether.



   (B) The magnesium salts can be removed, but this is not necessary. Generally, the mixture resulting from the reaction is poured into a suitable vessel where it is placed (the ice pounded, there is hydrolysis according to the formulas;
 EMI3.2
 
These hydroxy compounds readily polymerize on dehydration, giving initial and intermediate condensation products, soluble in ether and pooling in the ether layer. This solution is washed to remove the acid and then concentrated, resulting in a viscous liquid suitable as an adhesive and as a coating.

   The condensation and polymerization of this viscous liquid can be continued by suitable heating, for example 100-200 to obtain parts having the desired flexibility or hardness. In many cases there is an advantage in continuing the condensation of the liquid. It is heated in situ. that is to say at the very place of his employment
When the reaction product described above is gradually heated to 200 C for more than 24 hours and then kept at 200 C for 48 hours, a clear, colorless, odorless solid having the consistency of horn is obtained. The density is 1.19 and the refractive index is 1.423. On analysis, this polymer gave 23.05% 0, 6.02% H, 38:; lofa Si, and 32.8% 0.

   As a result, there is an average of 1.41 methyl groups per silicon atom. The dielectric constant is 3.7 to 26 and 3.6 to 56 At these same temperatures, the power factor under 60 cycles is 0.008 and 0.0045 *. This substance is insoluble in water, alcohol, glycol, carbon tetrachloride and bromanaphthalene. It is difficult to ignite, crude slowly leaving white silica ash. It can be heated in air at 200 C for several days without obtaining discoloration, melting, or other modifications, except for a slightly greater brittleness.

   At 300, an oxidation occurs in air which breaks up the product in 24 hours,

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 On the other hand, one can heat at 5500 in vacuum for 20 hours without disintegration and with yellow ooloration as the only change. During heating above 200 0 in vacuum there is evolution of vapor d. water, showing that condensation is continuing.



   The polymerized methylsilicone obtained differs from the silicones already described in the literature, not only by its composition, but by its properties. It is set by heat to a degree unknown in other silicones. It becomes infusible on heating and retains its shape even at 550 in vacuum. The solid polymer is clear, colorless, non-sticky, contrasting with the polymerized phenylsilicates, brown in color and the like% glue, which was the only type already known silicones.



   The structure of this horn polymer is not completely known. However, it can be assumed that it comprises a network of silicon-oxygen chains in which the methyl groups are linked to the silicon atoms. Thus, the condensation of dimethylsilicol presumably proceeds as follows t
 EMI4.1
   etc ...



  Such chains of alternating Si and 0 atoms can end, for example, with an OH group, which can continue the reaction, or else with a -Si (CH3) 3 group, preventing the reaction from continuing t
 EMI4.2
 Whenever an Si (OH) 3 group enters the chain, it becomes evident that there may be additional side bonds t
 EMI4.3
 In this way, a network structure can be obtained during the subsequent condensation.
 EMI4.4
 However, it is conceivable that the Si (OH) 3 group can also terminate a chain!
 EMI4.5
 methylsiliconic acid can also terminate a chain.

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   As noted above, the -Si-0 chain network can end in a variety of groups and can ratify by oxygen bridges. The mechanical properties of the solid polymer appear to depend to a large extent on the branches at the main chain and the length of the various chains. These factors can be modified by changing the proportions of the reactants according to the following examples! EXAMPLE II - (A) Molecular proportions of silicon tetrachloride and mangesium-methyl bromide are reacted in the cooled ether solution as described in Example I.

   In this case, the main derivative is methyl silicon trichloride, although small amounts of di- and tri-methylated derivatives are obtained simultaneously by the reactions mentioned in paragraph A of Example I, (B). pour the cold ethereal solution onto crushed ice to hydrolyze the methylsilicon chlorides, as in paragraph B of Example I. The products soluble in ether are separated from water and washed until disappearance of the acid.

   This ethereal solution of hydroxylated and partially condensed compounds can be used as it is as an adhesive or it can be concentrated by evaporating the% ion from the ether at room temperature, (c) The condensation can be continued, if desired, at a temperature of between 20 and 100, On evaporation of the solvent gives up a sticky mass which hardens after a few days giving a hard and brittle solid, At temperatures close to 100, the condensation is rapid and gives after one hour a brittle solid , hard, glassy, infusible and insoluble in water and in usual organic solvents, Analysis indicated 18.55% c, 4.58% H, 40.10% Si and 36.77% 0. The number of methyl groups per silicon atom is 1.08.



   According to the theory developed above, this solid polymer can be composed of a lattice of -SI-0 atoms with on average one methyl group per silicon atom, according to formula!
 EMI5.1
 

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 EXAMPLE III- (A) To a cooled ethereal solution of 1 mol of silicon tetrachloride is slowly added 2 to 2 1/4 mol of methylmagnesium bromide. The procedure is that of the previous example. Mainly silicon-dimethyl dichloride is obtained, together with smaller amounts of mono- and tri-methylated derivatives.



   (B) The hydrolysis of the reaction product is carried out as in the previous examples. The hydroxylated compounds accompanied by their partial condensation products remain dissolved in the ethereal layer which is washed and from which the ether is separated by distillation at 36. An oily liquid remains which loses water on subsequent heating but does not become solid., (0) The oily liquid obtained in B, heated to a raised temperature for a long time, for example 4 hours in air at 120, gives a gummy and soft gel, insoluble in customary organic solvents, infusible and heatable up to 260 * without apparent change. The composition contains 27.30% C; x 6.5% M; 30.98fi Si and 35.22% C.

   So there are on average 2.06 methyl groups per silicon atom.



   Based on the theory of structures developed above, the unitary link of the chain is t
 EMI6.1
 we can get a linear chain such that t
 EMI6.2
 chains which may end with OH groups or with -si (CE'3) 3 groups and there is very little chance that cross-links can be established due to the relative scarcity of groups -Si (However, the analysis shows a considerable excess of oxygen compared to that required for a chain containing only one element (CH3) 2SiO.

   It is therefore possible that the oxygen was found fixed during the heating of the substance and in a way which has not been clarified, but which gives the product its gummy character,
The compositions obtained according to the above examples are all derivatives of normal dimethylsilicone and of its polymers, the variations being made intentionally, so as to modify the properties of the product and to allow particular applications thereof. The term methylsilicone used in the present description in fact includes all chemical and special compounds.

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 they include condensation products and polymers with various molecular weights but containing silicon, oxygen and at least one methyl group attached directly to silicon.

   There is at least one methyl group attached to certain silicon atoms and, preferably, at least one such group on each of the silicon atoms belonging to the same molecule. Usually, the polymer should contain between about 1 and about 2 methyl groups on average per silicon atom present.



  The products which have the most diverse applications are polymers containing an average of 1.3 to 1.7 methyl groups per silicon atom.



   The methylsilicones according to the invention usually have a resinous character. In their final form, these polymers have the advantage of a thermal stability superior to that of usual organic coatings and binders, and they do not decompose leaving conductive carbon residues. As these new substances are exempt from the limitations presented by purely organic substances, they can be used with advantage with mineral fillers or fibers, or flakes: asbestos, mica, glass wool, etc.



  The resulting insulators can withstand higher temperatures than common organic binders. As a result, electric machines can be heated to higher temperatures.



    Here is an example of isolation by methylsilicones; ; The liquid coating composition comprising a partially polymerized methylsilicone and a volatile solvent which is evaporated by heat can be applied to a metallic conductor, such as a copper wire, which continues or completes the polymerization of the silicone in situ. . In some cases it may be advantageous to cover the conductor with a fibrous material, such as asbestos, glass wool, cotton or paper before carrying out the solution treatment. As another method, one can coat and partially impregnating the fibrous envelope disposed on the conductor with methylsilicone, winding the soled conductor in the form of a coil and then heating the latter to complete the polymerization of the silicone.



   Insulating sheets can be prepared by treating fabrics, inorganic or organic felts, or paper, with methylsilicone. Insulating sheets can also be prepared by bonding mineral flakes with polymerized mtbylsilicone. Some of these silicones wet and adhere to mica and are advantageous for bonding mica flakes and making laminated sheets. Polymerized methylsilicone containing on average

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 about 1 to 1.5 methyl groups per silicon atom are especially suitable for this purpose. Mica sheets agglomerated with methylsilicone have high dielectric strength and extreme heat resistance.

   They still hold at 250-300 C, without swelling or separation of the binder from the mica flakes,
Films or sheets of a clay such as bentonite can be treated with advantage with a polymerized methylsilicon composition. This application has been described in Belgian Patent No. 438,491 / filed by the Applicant Company on March 29, 1940. Glass fibers can be coated with this composite material and sheets similar to those of paper can be prepared, in accordance with the description of this same patent. Insulations of this kind are particularly suitable for use at elevated temperatures.



   In addition to their use as insulators, methylsilicones, in their various forms, can be used as a protective coating, for example for glass ampoules and parts which are exposed to exceptional temperatures or to the action of hot particles in suspension. . With or without the addition of pigments, such as graphite, these substances can be used for the coating of metallic surfaces, for example for the casings of metallic vacuum tubes.

   The high heat resistance of these silicones makes them perfectly suitable for such applications. The silicone compounds according to the invention can be used as components of semiconductor coatings, coatings which include well-defined levels of conductive powder, carbon, silicon carbide, powdered metals, conductive oxides, etc., so that the dried coating achieves a determined ohmic resistance.



   Methylsilicones can be used as a sealing material, for example to make vacuum-tight joints between glass and metal. If a silicone solution is applied around an imperfect seal, and heated to remove the solvent and obtain a solid polymer, all defects in the primitive seal can be removed.



   In certain cases, it may be advantageous to polymerize together mixtures of compounds each having a particular average number of methyl groups per silicon atom. This is achieved, for example, by mixing in suitable proportions the mono-silicon chlorides. and dimethyls. then by hydrolyzing the mixture and dehydrating the final product. In other cases, these products can be hydrolyzed separately, mixed and dehydrated together.

   However, in

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 in such cases the components must be mixed before the condensation is very advanced, otherwise the polymers become Incompatible * For other applications it may be advantageous to polymerize each of the silicones in the solid state, then mix and grind them together, to obtain a composite mass. In this way, one can best achieve the desired properties for each application.



   All of the foregoing polymers, individual or polymerized together, or still mixed after polymerization, can be incorporated into other substances to modify their properties. As such substances, mention will be made of natural or synthetic rubbers; tars, asphalts and skate, especially wood tars, petroleum asphalts and vegetable pitches; natural resins, such as rosin, copal, shellac, etc.: synthetic resins such as those based on phenols and aldehydes, ureas and aldehydes, alkyd resins, coumarone resins, vinyl resins, resins of the entire acrylic series, etc ...;

   cellulosic materials such as paper, organic or inorganic esters of cellulose, etc. In some cases, hard and brittle polymers can be ground for use as castings in substances as mentioned above. In other cases, especially if the silicone is compatible with the substance to which it is to be incorporated, it can be taken in the form of a liquid polymer or. relatively soft, low molecular weight before incorporating it into the substance to be modified.



   The low molecular weight polymers described are also soluble or dispersible in oils such as those of flax, Chinese wood, peril, soybean, etc., pure or mixed with solvents, pigments, plastics. - tifiers, siccatives and other constituents of liquids for coatings which, once dried in the oven baked in an oven, have great resistance to heat.



     Laminar products can be produced by superimposing fibrous sheets, organic or inorganic, each coated and impregnated with methylsilicone, then by exerting the action of heat and pressure on the whole. Molded parts and molding compositions are also obtained by means of silicones according to the invention.

   If desired, a filling material, such as asbestos, glass wool, talc, quartz powder, wood flour, etc., can be incorporated before the molding, which is carried out by heat, possibly under pressure, in accordance with plastics technology,

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We will now describe an accelerated process for dehydration of orgenosilicola making it possible to obtain condensed or polymerized materials similar to the adhesives described above.



   To abbreviate the description, it will be appropriate to call "silicol" any material containing both organic radicals and at least one OH group attached to a silicon atom t RxSi (OH) 4-x,. In this formula, R denotes an alkyl, aryl, etc. radical which can unite directly to the silicon atom and x an integer not exceeding 3. R can for example be a methyl group. Broadly speaking, the term silicones will also denote the dehydration products of silicols ot corresponding to the formula RxSiO4-x as well as the polymers of these products, R and x have the same meaning as above.



   The silicols can be prepared, for example, by hydrolyzing the corresponding halides, then condensing or dehydrating them to obtain the corresponding polymerized silicones. We have seen above, for example, that a mixture of CH3Si (OH) 3, (CH3) Si (OH) 2 and (CH3) 3SiOH in the required proportions provides a silicone capable of polymerization and the procedures for this have been indicated. last t after a high initial speed, the condensation slows down more and more as the reactive OH groups disappear.



   When some silicols are condensed by heat to form silicones, it happens that the partially condensed liquids are so volatile that a large part of the silicol evaporates before coniesation and polymerization. This effect is particularly important when the number of organic groups attached to silicon significantly exceeds that of hydroxyl groups.



   According to the invention, this difficulty is avoided and a higher dehydration yield is obtained by carrying out the condensation with the presonce of a desiccant. In the case of dimethylsilicols for example, the desiccant removes the water produced by the reaction
 EMI10.1
 which becomes faster at any given temperature * In formulas, x is an integer greater than 1.



   Any dehydrating agent can be used, for example boric acid esters, i.e. alkyl borates (methyl, ethyl, propyl, isopropyl, butyl, ischutyl, amyl, hexyl, heptyl , etc.), or aryl borates (phenyl, tolyl, xylyl, naphthyl, etc.), or else orthoborates

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 substituted such as phenyl and diethyl, m-tolyl and di-isobutyl, etc.



  The silicols can be dehydrated with antimony halides; trichloride, pentachloride, tribromide, pentabromide, etc .; oxides, halides and oxyhalides of phosphorus pentoxide, trichloride, tribromide, pentachloride, pentabromide, dibromotrichloride, oxychloride, oxybromides, oxybromodichloride; sulfuric acid; boron halides, chlorine and fluoride; Portand cement; certain ethylene diamine amines; diethylene triamine; triethylenetetramine, etc ... activated oxides such as alumina or silica gel;

   eto.,
The level of desiccant can vary between wide limits, in particular as a function of the particular silicol to be dehydrated, the degree of dehydration sought and its speed, the nature of the desiccant, the dehydration temperature, the use reserved for the dehydrator. dehydration product, etc. However, in general, the level of desiccant does not exceed by weight that of the silicol to be dehydrated and can be reduced between 0.1 and 10 or 20% by weight, EXAMPLE IV -
A partially condensed methylsilicol having an average of two methyl groups per silicon atom is mixed with half its volume of ethyl borsa.

   The mixture heated to 190 C gives a solid polymer after 10 minutes. In the absence of ethyl borate or other desiccant it would take several hours at 190 C and a large amount of silicol would be lost by evaporation. Analogously, a mixture of the same liquid methylsilicol with 20% of its volume of ethyl borate provides a polymer on heating for 30 minutes at 170 ° C at this temperature and without desiccant, it would be necessary to heat for several days to obtain a solid polymer. .



   By heating a methylsilicol with 1.6 methyl groups per silicon atom to 150 ° C., a very gradual increase in viscosity is observed. In other words, the product is solid after 15 minutes at this temperature by addition of 10% of its volume of ethyl borate.



   The dehydration with boric esters is carried out in accordance with the following reactions;
 EMI11.1
 Boric acid or intermediate product remains dissolved in silicone

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   polymeric, while the ethyl alcohol liberated evaporates at the condensation temperature, In the case of the higher alkyl and aryl borates, all the non-volatile products of the reaction remain dissolved or dispersed in the solid sili- oone, EXAMPLE V -
By heating for 15 days at 175 ° C., the viscosity of the liquid methylsilicol is slightly increased, containing an average of 1.6 methyl groups per silicon atom.

   On the other hand, by adding 1 to 5% by weight of one of the desiccants below, solid condensation products are obtained under the following conditions: t 1 - antimony pentachloride gives an uncolored solid. Immediately at room temperature,
2 - Sulfuric aoide reacts in the same way at ordinary temperature and gives a slightly colored solid.



   3 '- Ethylene diamine gives a solid polymer by heating for one hour at 120 C,
In the examples below the dehydration of methyl silicols has been shown, but any other silicol may be dehydrated partially or substantially all by mixing with a desiccant. Aryihalogenated silicols can be dehydrated in the same way, such as chlorophenyl silicols, methylarylsilicols, in particular methylphenylsilicols, arylsoxysilicols, and more especially aryloxyarylsilicols, in particular phenoxyphenylsilicols, and mixtures of which are derived from such earlier silicols. known.



   It is obvious that the invention is not limited to the specific dehydrating agents mentioned above and that any dehydration catalyst can be used, for example any of those mentioned in the description above. desiccant can be homogeneous, that is to say that, both in its initial state and in the form of a hydrolysis product, it does not separate as a distinct phase from the silicol or the silicone. An example is ethyl borate, as well as all boric acid esters.

   The desiccant can also be heterogeneous, for example portand cement or sulfuric acid, which, both in its normal state and after reaction, separates from the silicol or the silicone. Preferably, a homogeneous desiccant will be used. and especially some of the esters of boric acid, In some cases *

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 it may be advantageous to use an alsoyl borate to dehydrate an alkylsilicol, and an aryl borate to dehydrate and condense an arylsilicol.



   The above description shows that partial or complete dehydration can be carried out quickly and economically and thus prepare the condensation of the silicol in polymerized silicone. The novel materials thus obtained may comprise silicols (such as methylsilicol). in which a desiccant is incorporated. Novel and useful products can also be obtained in this way from a mixture of silicols and a desiccant, such as an ester of boric acid, for example ethyl borate. Once dehydration has been obtained, these new dehydration products, added or called modifying agents, can be used in industry, and in particular for producing electrical insulating compositions.



   By way of particular but important example, organic silicon compounds in which the bivalent organic radicals are each bonded to two different silicon atoms will now be described.



   We already know compounds of silicon, oxygen and bivalent organic radicals, such as, for example, pentamethylésilicone ((CR2) 5SiO) x by hydrolysis () of the corresponding dichloride followed by dehydration of the silicol obtained, (Bygden "" Berichte ", volume 48 , page 1238, 1915 and the thesis Upsala, 1916 p.105 to 107) * The substance obtained is a derivative of substitution of silicon oxide It is solid and polymerizes along the chain -Si-C-Si-C In penta-methylenesilicone gas, the group of atoms is as follows:
 EMI13.1
 As can be seen from the formula, each pentametbylene divalent radical is attached to a single silicon atom.



   The new compounds which are the subject of the invention are polymers in which a large number of silicon atoms are found linked to each other by divalent organic radicals according to formula (A).
 EMI13.2
 
In this formula, to show the constitution clearly, we have doubled the structural unit (B);

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 EMI14.1
 R, represents an organic radical which could connect per its valences two
 EMI14.2
 silicon atoms separated in the molecule for example, in the :: 'ormu1e (A), R represents a phenyljie radical, and the polymers poss3J;

  .iE structure it.
 EMI14.3
 we can abbreviate the formula (0) in the form (D) t
 EMI14.4
 
 EMI14.5
 By analogy, when R of formula (A) represents a radical m ± th = 11.ne, or polymethylene, for example the polymers object of Itinventicn have the structure (E) s
 EMI14.6
 
 EMI14.7
 lorms examples of radicals R which may exist in formulas A and B, we will indicate dimethylene ¯ (.2) 2, trimethylene - (CI: t-) 3-t tetrameth "rlene - (riû) 4- le pontamêthylène - (#) 5¯, hexaméùy.lene ¯ (rl2) 6- or, in general, any straight aliphatic chain of the general type - (CH2) x- x being an integer which can be understood for example between 1 and 20 or more.

   As other examples of divalent radicals) R can be p. pt-diphenylene or an ali- radical
 EMI14.8
 phatic ratified as methylmeth; elene 1 or dim6ethylmethylene -V (C &) 2 or "Cfr3 CH or 2,3-dimethyltetramethylene -CH -1i-C [{-Cn2; alkyl-substituted aryl radicals, such as those for example of the general type - c6Irnt-, where R 'de-
 EMI14.9
 sign an alkyl or aralkyl radical, or aryl radicals sbtitués by alkyl radicals belonging to the general type) in which R "denotes -CH-
 EMI14.10
 an aryl or alkylaryl radical.

   Specific examples of the radicals R1 and R "will be described in the following,
In the polymers represented by formula (A), the bivalent organic radicals indicated by R can be similar or different. For example, one R radical can be methylene and another R a branched radical, such as
 EMI14.11
 methylmethylene; or else a substituted or unsubstituted phenylene radical, a poly-methylene radical, etc.

   As a specific example of this type of compound, one will describe one

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 of them which contains substantially equal numbers of pentamethylene and phenylene radicals. In such polymers, the silicon atoms and the divalent organic radicals are found randomly linked according to formula (F);
 EMI15.1
 
Thanks to the introduction of different bivalent organic radicals into the organ-silicic compounds of the invention, the properties of the polymer can be modified at will,
Organo-silicic compounds comprising several organic radicals with valence 1 and 2, attached to silicon atoms can also be manufactured according to the invention.

   Such compounds differ from those represented by formulas (A) and (B), in that the divalent organic radicals R of the formulas have been replaced by univalent organic radicals, such as alkyls, aryls, alkylaryls, aralkyls, etc.,. Polymers of this type contain the skeleton (G)
 EMI15.2
 In this formula, R represents the same divalent organic radical or several such different radicals and A one or more different univalent radicals.



   According to this formula, we see that if we replace the bivalent radicals by twice their number of univalent radicals, we obtain a product having the structure (H):
 EMI15.3
 In this case, the linear polymer cannot provide a three-dimensional network.



  In those silicon compounds with univalent and bivalent organic radicals, the average number of univalent radicals should not exceed twice the average number of divalent radicals, and preferably should be less than this number. By proportioning the reactants such that the average number of univalent radicals remains less than twice the average number of bivalent radicals, crosslinks can be made during polymerization resulting in a more rigid structure.

   As univalent radicals represented

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 by A in the above formulas, we will indicate the methyl, ethyl, propyl, isopropyl, butyl, isobutyl, amyl, hexyl, heptyl to octadecyl radicals, and the upper radicals of the aliphatic series; halogenated or non-halogenated aryl radicals, such as phenyl, mono- or polyalkylated phenyl, naphthyl, alkyl-naphthyl or tetra hydronaphthyl; anthracyl, benzyl, etc.



   Organosilicon compounds can be produced with bivalent organic radicals, joining silicon atoms according to any of Schemes (A) to (H) above, but some of these ra- organic dicals with oxygen atoms, provided that the number of these atoms is not greater on average than 1 for two silicon atoms. Polymers of this type have, for example, one of the structures. (1), (J), (K):
 EMI16.1
 formulas, in which A and R have the same meaning as above,
These different substances can be prepared by the known means of organic chemistry.

   For example, one can react a silicon halide, such as tetrachloride, tetrabromide, etc., with at least two molar equivalents of the: dimagnesium derivative of a dihalide of an organic radical, for example. dichloride, dibromide or diiodare.



  EXAMPLE VI -
The preparation of a polymer of the type represented by the formula (F) of the type (A) will first be described.



   1 - 1.65 moles of p-dibromobenzene are reacted in ethereal solution over 3.45 months of magnesium, from which results a two-phase system containing 1.32 mols of phenylene dimanesium dibromide:
 EMI16.2
 2 - Slowly add the magnesian solution, while stirring, to a solution

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 ethereal concentration of 1.32 mols of silicon tetrachloride. The mixture is heated under reflux for 30 minutes, and a polymer of phenylene silicon dichloride is obtained.
 EMI17.1
 
3 - 1.32 mols of the dimagnesium derivative of a mixture of isomeric dichloropentanes dissolved in ether are then added, with stirring,

   to the mixture obtained under @ - then the resulting mass is heated under reflux for two hours
 EMI17.2
 
4) The organo-silicic compound is isolated by pouring all the product into water, dissolving the magnesium salts. After evaporation of most of the ether, a yellow resin is obtained, extremely viscous, soluble in benzene.

   Once the ether has completely evaporated, the yellow rbsin becomes solid, clear and has a non-sticky surface,
The product obtained in this example can be defined as resulting from the reaction of a silicon halide (here SI, 01 4), with two molecular equivalents of dimagnesium derivative and two organic dihalides (here a dichloride and a dibromide), EXAMPLE VII -
Next, the production of a substance represented by formula (H) will be described. First, the first two steps described in Example VI under N ′ and 2 are carried out.



   3) Is added slowly, with stirring, to the product resulting from step 2 an ethereal solution of methylmagnesium bromide containing 2.1 mols per mol of phenylsilicon dichloride. the reaction is
 EMI17.3
 
4) Methylphenylmesilicon chloride is hydrolyzed by pouring the reaction product onto crushed lace. The reaction is;
 EMI17.4
 The ethereal layer contains the product of hydrolysis. We separate it and wash it; after evaporation of the ether, there is a yellow resin, soft and sticky.

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   5 - The product obtained under 4 - is condensed (dehydrated), gradually heating it to 110. After two hours at this temperature, the product is still liquid, but solidifies if heated an hour longer at 1208. The substance is brown, soft, it dissolves in benzene, toluene and l 'acetone.



  It is made infusible by prolonging the heating. The setting and dehydration can also be sccéldrer by incorporating a catalyst, such as ethyl borate, as described above.



   The resin obtained can be defined as a dehydrated product before hydrolysis of the substance obtained by reaction of more than one and less than two molar equivalents of the magnesium of an organic monohalide (here 1.26 mol of bromide of methylmagnesion) on the reaction product of a silicon halide with a molar equivalent of the dimagnesium derivative of an organic dihalide (here phenyledenedimagnesium bromide).



   Of course, the invention is not limited to the specific methods mentioned in the examples above, nor to the specific reagents, nor to the proportions chosen *
In general, the invention makes it possible to produce chemical compositions for which univalent and polyvalent organic radicals are attached to them silicon atoms.

   These compositions are obtained by reacting, for example, a solution of a pure silicon halide with a solution containing one molar equivalent of the dimagnesium chloride of a crganic halide, then reacting the resulting solution with a solution containing two molar equivalents of the magnesium. of an organic mouchalogenide, finally, by isolating the organic silicic compound obtained from the reaction mass,
According to a method suitable for example for the preparation of a silicon cxxopsé with divalent organic radicals and oxygen, the reaction is carried out between a silicon halide and more than 1,

  5 but less than two dimagnesium molar equivalents of an organic dihalide, then the resulting product is hydrolyzed and the hydrolyzate dehydrated in the presence or absence of a dehydrating agent.



   Here is an example of application of these resins new in the industry!
A metallic conductor, for example a copper wire, is coated with a liquid comprising a volatile solvent and a resinous polymer which is liquid or solid but soluble and curable by heat. The coated wire is heated to evaporate the solvent and harden the solvent. polymer. In this way, the polymerization is continued or completed in situ.

   For the manufacture of certain electric cables

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 it can also be advantageous to wrap the conductor with an organic or mineral fibrous material, such as asbestos, glass, cotton, paper, before carrying out the treatment with the liquid resin. coating the conductor with the fibrous material, then impregnating it, at least in part, with the liquid resin, winding the conductor properly and heating the coil to solidify it. resin,
Laminar insulators can be obtained by treating fabrics, felts or papers with resinous compositions as described.

   Inorganic flake substances can also be incorporated into these new resins and sheet insulation can be prepared, for example by means of mica and these resins. can also combine with these sheets clays, such as bentonite, in accordance with the aforementioned Belgian patent 438,491, filed by the applicant company.



   Another application of these resins is the coating of glass parts, such as bulbs, or of metals such as iron, steel, copper, etc.! or even the setting of seals. as indicated above,
In certain cases, it may be advantageous to mix the various polymers obtained according to the invention. At other times, non-condensed or non-dehydrated products can be mixed in order to effect their intercondensation with possible dehydration of the sucoeptible products to be so. that they remain compatible with each other.

   It is also possible to mix the solid resins after having grinded them, or to grind them together to obtain a composite mass,
It is also possible to incorporate into these resins polymerizable products based on silicon, such as polymerized methylsilicones, polymerized alkylsilicones, polymerized arylsilicones, polymerized haloarylsilicones, etc. The resulting non-totally polymerized mixtures can be intercondensed with dehydration in the presence or in the absence of homogeneous or inhomogeneous dehydrating catalysts, as has been explained. In these semi-solid or solid liquids, polymerized individually or together at any stage of polymerization, modifying substances can be incorporated such as pitches, asphalts, tars,

   natural resins, synthetic resins, cellulose derivatives, etc. According to the methods described above, when the silio resin is compatible with the substance, this resin can be used in the liquid state or at low molecular weight before producing the resin. association sought.



   The new siliceous resins described can, on the other hand, be treated.

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 EMI20.1
 teas firing in the manner known in the plastics industry, for example by incorporating liquid substances, plasticizers, interior lubricants, etc.



   The low molecular weight polymers obtained according to the invention can be dissolved or dispersed in fatty oils, either alone or with solvents, pigments, siccatives and plasticizers, etc., as has been indicated,
Finally, it is possible to produce agglomerates with a laminar structure with these complex resins, as has been described above. Powdered or fibrous fillers or fillers in the form of pellets can be incorporated into these laminar materials.
 EMI20.2
 



  PES li il E -t- ¯, ¯, ¯; ¯; ¯; ¯; ¯ī il New resinous substances, liquids, gels, in gel or solid obtained by dehydration of one or more silio18 contain on average more of a group or and less than three per silicon atom present.



  II - Methods of preparation consisting in intercondensing and dehydrating organoeiliclques compounds corresponding to the simple formulas Si (d3) 2 (OH) 2i S1 (CI-3) 3 (OH), 5i (oW) (orr) 5, sian <ori> 4-n, ... Ri-Si (ARt) ^ Ro-wsi (AR) -9 -g, -xià2- -R'Sià2-, in which R denotes a univalent radical (alkyl, aryl, etc.) , R ′ an atom or divalent radical (Ot p-phenylene, l n8, etc.) and A a univalent radical, The different R, R ′ or A of the same polymer may be similar or different.
 EMI20.3
 



  The preparation is made from silicon halides in solution in an incogellable solvent, at low or very low temperature, and one or more Grignard magnesians, the role of which is to incorporate the groups A, R into the resin. or R 'chosen, then by hydrolysis at O' of the product obtained; after washing and vaporization of the solvent, the resinous material remains in a state of condensation which depends on the thermal history of this product.



   III- Catalysis of dehydration of silicols to obtain the resin, by addition of dehydrating agents, preferably boron esters.

** ATTENTION ** end of DESC field can contain start of CLMS **.


    

Claims (1)

IV - New industrial products consisting of organosilicon resins, moldings, coatings, insulators, etc. based on these resins and as described, ** CAUTION ** end of field CLMS may contain start of DESC **.