Depolymerization of silicones obtaining organochlorosilanes

Abstract

The present application relates to a process for preparing organochlorosilanes CS by reacting at least one silicone S with a metal or metalloid chloride CM in the presence of at least one metal salt catalyst SM, the metal or metalloid chloride CM being different from the metal salt SM.

Description

Technical Field

[0001] The present invention generally relates to the reuse of organosilicon polymers. More specifically, the method of the present invention relates to the depolymerization of organosilicon polymers to obtain organochlorosilanes. This method advantageously enables the recycling of used or unused organosilicon polymers for the preparation of organochlorosilanes, which can then be used in polymerization reactions. Background Art

[0002] Recycling of industrial products and used silicone products is an issue that is gaining attention. Recycling of silicone can reduce gaseous (CO, CO2) emissions associated with the silicone industry by 75% and reduce silicone waste by 65%.

[0003] The depolymerization of organopolysiloxanes to fluorosilanes is known and has been described. The reaction is favorable from a thermodynamic point of view, since the Si-F bonds are very strong (about 135 kcal / mol) compared to the Si-O bonds of organopolysiloxanes (about 110 kcal / mol). However, these processes have certain disadvantages, in particular the release of volatile products or the cost of the fluorine source.

[0004] On the other hand, Si—Cl bonds are relatively weak (especially 90 kcal / mol), so depolymerization of organopolysiloxanes to organochlorosilanes is disadvantageous.

[0005] The depolymerization of polydimethylsiloxanes to give chlorosilanes is known from Enthaler et al. (J. Appl. Polym. Sci. 2015). The catalyst used is an iron salt. However, this process requires a large amount of catalyst (7.5% by weight of catalyst relative to the weight of the organopolysiloxane), a corrosive chlorine source of the acid chloride type and high temperatures of about 170-190° C.

[0006] It is therefore of interest to provide an alternative process for the depolymerization of organosilicones to organochlorosilanes. It is particularly interesting to provide a catalytic system which enables this depolymerization to be carried out at lower temperatures, enables the amount of catalyst used to be limited and enables the use of other chloride sources. Summary of the invention

[0007] One object of the present application is therefore to propose a process for depolymerizing organosilicones which is efficient and enables good yields of organochlorosilanes to be obtained.

[0008] Another object of the present application is to provide a catalytic system for implementing this method.

[0009] Yet another object of the present application is to propose a simple and non-hazardous catalytic system compatible with the industrialization of this process.

[0010] Other objects may also appear by reading the following description of the invention.

[0011] These objects are achieved by the present application, which relates to a process for preparing organochlorosilanes CS by reacting at least one organosilicon S with a metal or metalloid chloride CM in the presence of at least one metal salt catalyst SM, the metal or metalloid chloride CM being different from the metal salt SM.

[0012] Silicones, also known as organopolysiloxanes, are polymeric materials containing alternating silicon and oxygen atoms and having various organic groups bonded to the silicon.

[0013] In the context of the present invention, the terms "silicone" or "silicone product" or "silicone polymer" or "organopolysiloxane" are understood to mean polymers comprising a siloxane backbone (Si-O-Si) with alternating silicon and oxygen atoms, with various organic groups bonded to the silicon. These silicone polymers can be liquid or solid, depending on the molecular weight and the degree of crosslinking.

[0014] The silicones S of the invention may be of any type; they may be, for example, linear organopolysiloxanes O, such as oils or gums, or branched organopolysiloxanes O, such as resins.

[0015] The organopolysiloxane O may in particular be an oil or a gum and preferably has a dynamic viscosity of between 50 and 600,000 mPa.s at 25° C. or a consistency expressed in tenths of a millimeter of between 200 and 2000 at 25° C. All viscosities mentioned in this specification correspond to so-called “Newtonian” dynamic viscosity values ​​at 25° C., i.e. dynamic viscosities measured in a manner known per se using a Brookfield viscometer at a sufficiently low shear rate gradient that the viscosity measured is independent of the rate gradient.

[0016] The term "gum" is used for organopolysiloxane compounds having a viscosity typically greater than 600,000 mPa.s, which corresponds to a molecular weight greater than 260,000 g / mol.

[0017] These organopolysiloxanes O may contain one or more functional units, for example:

[0018] -OH;

[0019] -H;

[0020] -alkenyl, in particular containing 2 to 6 carbon atoms, preferably vinyl;

[0021] -O-Alk, wherein Alk represents an alkyl group containing 1 to 15 carbon atoms, preferably 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, preferably methyl;

[0022] -(O-Alk) x , wherein Alk represents an alkyl group containing 1 to 15 carbon atoms, preferably 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, preferably a methyl group; and x represents an integer between 2 and 200;

[0023] - a linear or branched alkyl group containing 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, which is substituted by at least one fluorine atom, for example 1 to 10 fluorine atoms, for example (C1-C5)alkyl-CF3, which alkyl group is linear or branched;

[0024] - amino groups, in particular (Alk)-NH2 or (Alk)-NH-(Alk)-NH2, wherein Alk represents an alkyl group containing 1 to 5 carbon atoms;

[0025] -Cyclic amines, such as -(CH2) z -O-piperidine, wherein z represents an integer from 1 to 5, preferably 3; and the piperidine may in particular be substituted by one or more alkyl groups containing 1 to 3 carbon atoms, preferably methyl; preferably, the substituted piperidine is a group

[0026] Preferably, the functional unit is selected from:

[0027] -OH;

[0028] -H;

[0029] -alkenyl, in particular containing 2 to 6 carbon atoms, preferably vinyl;

[0030] a linear or branched alkyl group containing 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, which is substituted by at least one fluorine atom, for example 1 to 10 fluorine atoms, such as (C1-C5)alkyl-CF3, the alkyl group being linear or branched.

[0031] Preferably, the organopolysiloxane O may comprise one or more functional units, such as H, OH, alkenyl (preferably vinyl), aryl, cyclic amine, as defined above.

[0032] The organopolysiloxane O of the present invention may be partially crosslinked.

[0033] The organopolysiloxane O according to the invention may in particular be a used organopolysiloxane which has been used, for example, as a heat transfer fluid and is to be recycled, and with the process according to the invention it is thus possible to produce organochlorosilanes which can then be used directly in industrial processes. In the case of using used organopolysiloxanes O, the organopolysiloxane may then contain further components, such as additives, pigments, etc. The inventors have therefore shown that the presence of these further components does not interfere with the depolymerization reaction and the formation of the organochlorosilane CS.

[0034] According to one embodiment of the present invention, the organopolysiloxane O of the present invention comprises:

[0035] - at least 5 siloxy units, preferably at least 10 siloxy units, having the formula R c SiO (4-c) / 2

[0036] in

[0037] R, same or different, means

[0038] Contains 1-15 carbon atoms, preferably 1-12 carbon atoms, preferably 1-10

[0039] An alkyl group of carbon atoms, preferably 1 to 5 carbon atoms, preferably methyl;

[0040] An aryl group containing 6 to 10 carbon atoms, preferably a phenyl group;

[0041] and c = 0, 1, 2 or 3; and

[0042] - Optionally, one or more units having the formula R 1 d R e SiO (4-d-e) / 2

[0043] in:

[0044] R is as defined above

[0045] R 1 , the same or different, means:

[0046] An alkenyl group containing 2 to 6 carbon atoms, preferably a vinyl group;

[0047] Hydroxyl group (OH);

[0048] The group (O-Alk), wherein Alk represents an alkyl group containing 1 to 15 carbon atoms, preferably 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, preferably OCH3 or OC2H5;

[0049] Group (O-Alk)x , wherein Alk represents an alkyl group containing 1 to 15 carbon atoms, preferably 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, preferably a methyl group; and x represents an integer between 2 and 200;

[0050] a linear or branched alkyl group containing 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, which is substituted by at least one fluorine atom, for example 1 to 10 fluorine atoms, such as (C1-C5)alkyl-CF3, which alkyl group is linear or branched;

[0051] An amino group selected from (Alk)-NH2 or (Alk)-NH-(Alk)-NH2, wherein

[0052] Alk represents an alkyl group containing 1 to 5 carbon atoms;

[0053] Cyclic amines, such as -(CH2) z -O-piperidine, wherein z represents an integer from 1 to 5, preferably 3, and the piperidine may in particular be substituted by one or more alkyl groups containing 1 to 3 carbon atoms, preferably methyl, preferably the substituted piperidine is a group

[0054] ·hydrogen;

[0055] d=1, 2 or 3, preferably d=1 or 2, more preferably d=1; e=0, 1 or 2; and the sum d+e=1, 2 or 3.

[0056] It will be appreciated that in the above formulae, if multiple R groups are present or if multiple R 1 groups, they may be the same as or different from each other.

[0057] Preferably, in the above formula, R 1 , the same or different, means:

[0058] An alkenyl group containing 2 to 6 carbon atoms, preferably a vinyl group;

[0059] Hydroxyl group (OH);

[0060] a linear or branched alkyl group containing 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, which is substituted by at least one fluorine atom, for example 1 to 10 fluorine atoms, such as (C1-C5)alkyl-CF3, which alkyl group is linear or branched;

[0061] ·hydrogen.

[0062] In the present invention:

[0063] -Siloxy unit "M" represents a unit having the formula Y3SiO 1 / 2The siloxy units of

[0064] -Siloxy unit "D" represents a unit having the formula Y2SiO 2 / 2 The siloxy units of

[0065] -Siloxy units "T" represent units having the formula YSiO 3 / 2 The siloxy units of

[0066] -Siloxy unit "Q" represents a unit having the formula SiO 4 / 2 The siloxy units of

[0067] Symbol Y is R or R 1 .

[0068] The organopolysiloxane O may optionally comprise T and Q units.

[0069] According to a preferred embodiment, the organopolysiloxane O of the present invention is preferably selected from compounds having formula (I):

[0070] R 1 a R (3-a) SiO-(SiR2O) n -(SiR 1 RO) m -SiR 1 a R (3-a) (I)

[0071] in:

[0072] R, same or different, means:

[0073] Contains 1-15 carbon atoms, preferably 1-12 carbon atoms, preferably 1-10

[0074] An alkyl group of carbon atoms, preferably 1 to 5 carbon atoms, preferably methyl;

[0075] An aryl group containing 6 to 10 carbon atoms, preferably a phenyl group;

[0076] R 1 , the same or different, means:

[0077] An alkenyl group containing 2 to 6 carbon atoms, preferably a vinyl group;

[0078] Hydroxyl group (OH);

[0079] The group (O-Alk), wherein Alk represents an alkyl group containing 1 to 15 carbon atoms, preferably 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, preferably OCH3 or OC2H5;

[0080] Group (O-Alk) x , wherein Alk represents an alkyl group containing 1 to 15 carbon atoms, preferably 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, preferably a methyl group; and x represents an integer between 2 and 200;

[0081] a linear or branched alkyl group containing 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, which is substituted by at least one fluorine atom, for example 1 to 10 fluorine atoms, such as (C1-C5)alkyl-CF3, which alkyl group is linear or branched;

[0082] An amino group selected from (Alk)-NH2 or (Alk)-NH-(Alk)-NH2, wherein

[0083] Alk represents an alkyl group containing 1 to 5 carbon atoms;

[0084] Cyclic amines, such as -(CH2) z -O-piperidine, wherein z represents an integer from 1 to 5, preferably 3, and the piperidine may in particular be substituted by one or more alkyl groups containing 1 to 3 carbon atoms, preferably methyl, preferably the substituted piperidine is a group

[0085] ·hydrogen;

[0086] a is an integer and represents 0, 1, 2 or 3, preferably 0, 1 or 2, more preferably 0 or 1;

[0087] n represents an integer between 10 and 10,000, preferably between 10 and 5,000, preferably between 50 and 5,000, more preferably between 60 and 5,000, for example between 70 and 1,000;

[0088] m represents an integer between 0 and 100, preferably between 0 and 50, more preferably between 0 and 30, preferably m=0.

[0089] Particularly preferably, the organopolysiloxane O of the present invention is a compound having the formula (I)

[0090] Where R 1 , the same or different, means:

[0091] An alkenyl group containing 2 to 6 carbon atoms, preferably a vinyl group;

[0092] Hydroxyl group (OH);

[0093] a linear or branched alkyl group containing 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, which is substituted by at least one fluorine atom, for example 1 to 10 fluorine atoms, such as (C1-C5)alkyl-CF3, which alkyl group is linear or branched;

[0094] ·hydrogen.

[0095] Particularly preferably, the organopolysiloxane O of the present invention is a compound having the formula (I)

[0096] Where R 1 , which are the same or different, represent CH3, vinyl, H, (C1-C5)alkyl-CF3 or OH.

[0097] Particularly preferably, the organopolysiloxane O of the present invention is a compound having the formula (I)

[0098] in

[0099] R, identical or different, represents CH3 or phenyl, preferably CH3;

[0100] R 1 , the same or different, means:

[0101] An alkenyl group containing 2 to 6 carbon atoms, preferably a vinyl group;

[0102] Hydroxyl group (OH);

[0103] a linear or branched alkyl group containing 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, which is substituted by at least one fluorine atom, for example 1 to 10 fluorine atoms, such as (C1-C5)alkyl-CF3, which alkyl group is linear or branched;

[0104] ·hydrogen.

[0105] Particularly preferably, the organopolysiloxane O of the present invention is a compound having the formula (I)

[0106] in

[0107] R, identical or different, represents CH3 or phenyl, preferably CH3;

[0108] R 1 , which are the same or different, represent CH3, vinyl, H, (C1-C5)alkyl-CF3 or OH.

[0109] The organosilicon S of the present invention may also be a cross-linked organosilicon material type, such as a gel or an elastomer. The cross-linked organosilicon material may be obtained by polycondensation, free radical polymerization, thermal or UV radiation polyaddition, and the like.

[0110] Silicone products have a wide variety of applications. As an example, they can be found in food applications (e.g. moulds), medical applications and in the pharmaceutical sector, for example in bottle nipples, catheters, implants or tubes for medical applications. In technical industrial applications, silicone is often used as a material for seals or membranes. In the automotive sector, it is used for hoses, cable sheathing or insulation and as a cushioning material.

[0111] Silicone elastomers are cross-linked silicone materials that contain fillers, such as silica, to obtain good mechanical properties.

[0112] By varying silicone oil, fillers and additives as well as crosslinking patterns, silicone elastomers exhibit different properties and colors.

[0113] Silicone elastomers can be divided into three major categories known to those skilled in the art. Heat vulcanized elastomers (EVC or in English "high temperature vulcanisation (HTV)" or "heat cured rubber (HCR)") are silicone elastomers obtained from silicone compositions of very high viscosity containing silicone rubber and fillers. They are vulcanized at high temperatures, typically between 140°C and 200°C. Crosslinking is achieved either by free radical crosslinking catalyzed by peroxides or by addition reactions in which platinum compounds are used as catalysts.

[0114] Liquid silicone rubber (LSR) is a silicone elastomer obtained from a composition containing silicone oil and filler. Crosslinking occurs by addition reaction at temperatures similar to EVC, but usually much faster, by crosslinking the two components mixed just before the start of crosslinking.

[0115] The third category is silicones obtained by crosslinking at ambient temperature silicone compositions crosslinked by polycondensation or polyaddition reactions with silicone oils and fillers as raw materials. These elastomers are called in French “élastomère silicone vulcanisables à froid” (EVF, “room temperature vulcanization (RTV)” in English). These compositions are available in one-component and two-component systems.

[0116] In the process of the present application, the term "organosilicon S" is also understood to mean a silicone-based material, for example a material comprising at least 0.1% by weight of silicone relative to the total weight of the silicone-based material. The silicone-based material may comprise up to 100% by weight of silicone, preferably up to 99.9% by weight of silicone relative to the total weight of the silicone-based material. These silicone-based materials may also contain additives or fillers, such as colorants, silicon dioxide, calcium carbonate, calcium oxide, celite, quartz, titanium oxide, cerium hydroxide, magnesium oxide, mica, etc.

[0117] In the process of the invention, the metal or metalloid chloride CM comprises in particular metalloid chlorides, transition metal chlorides, alkaline earth metal chlorides, alone or as a mixture.

[0118] Preferably, the metal or metalloid chloride CM is selected from metal chlorides of the formula M'Clz, wherein

[0119] M' represents B, Al, Ti, Zr, Mg, Zn, Ca, Sb, Ge, Si or Cu, preferably B, Al, Ti, Zr, Mg, Ca, Zn, preferably B, Al, Mg, Zn, Ca, preferably B, Al;

[0120] z represents an integer depending on the valence of the metal M′, for example z represents 3, 4 or 5.

[0121] The metal or metalloid chloride CM is preferably selected from BCl3, AlCl3, TiCl4, ZrCl4, MgCl2, ZnCl2, CuCl2, CaCl2, SiCl4, GeCl4, SbCl5, alone or as a mixture, preferably BCl3, AlCl3, MgCl2, ZnCl2, CaCl2, more preferably AlCl3, BCl3, preferably BCl3.

[0122] The metal or metalloid chloride CM may be in the form of a solution in a solvent. This is particularly advantageous in the case of solid or gaseous metal or metalloid chlorides, so as to dissolve these chlorides in the reaction medium. The solvent may in particular be an organic solvent of the alkane, halogenated alkane or aromatic hydrocarbon type. Preferably, the solvent is selected from dichloromethane, n-hexane, n-heptane, toluene, xylene, 1,3,5-trimethylbenzene.

[0123] Preferably, the amount of metal or metalloid chloride CM used in the process of the invention is at least 50 mol %, preferably 50-800 mol %, preferably 50-300 mol %, for example 50-200 mol %, relative to the moles of Si—O.

[0124] Within the scope of the present invention, the number of moles of Si—O is understood to mean the number of moles of Si—O bonds of the organosilicon S.

[0125] In cases where the chemical formula of the starting silicone S is unknown, in particular in the case of formulated commercial products, the number of moles of Si-O can be estimated. In practice, for formulated products, the skilled person knows that the amount of filler is between 20 and 40% by mass, so by estimating the amount of filler as an average of 30% by mass, 70% by mass of silicone is obtained, which enables the calculation of the number of moles of Si-O bonds from the average molar mass of the repeating units.

[0126] The metal salt SM used as catalyst in the process of the invention is preferably selected from salts of elements of group 13 of the periodic table and transition metals. The metal salt SM is preferably a metal salt containing at least one halogen atom, preferably Cl, Br, I, F, for example of the formula MX m of metal halides, wherein:

[0127] M represents Ga, Ge, Al, In or Fe, preferably Ga, Al or Fe,

[0128] X represents Cl, Br, I, F, OTf, BF4, SbF6

[0129] m represents an integer depending on the metal M, and preferably, m represents 2, 3 or 4.

[0130] Preferably, the metal salt SM is selected from GaCl3, FeCl2, FeCl3, InCl3, AlCl3, GeCl4, preferably FeCl3, FeCl2, AlCl3, GaCl3, InCl3.

[0131] Depending on the properties of the metal salt, it can be dissolved in a solvent. The solvent can be an organic solvent of the alkane, halogenated alkane, aromatic hydrocarbon type. Preferably, the solvent is selected from dichloromethane, n-hexane, n-heptane, toluene, xylene, 1,3,5-trimethylbenzene.

[0132] Preferably, the amount of metal salt SM used in the process of the invention is 0.01-10% by weight, preferably 0.1-5% by weight, for example 0.1-2% by weight, relative to the weight of the organosilicon S.

[0133] Preferably, the amount of the metal salt SM used in the process of the present invention is 0.01-10 mol %, preferably 0.01-5 mol %, for example 0.1-2 mol %, relative to the molar number of Si—O.

[0134] Preferably, the Cl / Si—O molar ratio is from 1 to 3, preferably from 2 to 3, for example from 2 to 2.5, for example 2, wherein the amount of chlorine is the amount of chlorine originating from the metal or metalloid chloride CM and the number of moles of Si—O corresponds to the number of moles of Si—O bonds in the organosilicon S.

[0135] Advantageously and preferably, the reaction is carried out at a temperature of 0-200°C, preferably 0-150°C, preferably 20-130°C, more preferably 30-110°C.

[0136] The duration of the reaction can be from a few minutes to a few hours.

[0137] Those skilled in the art will know how to adjust the temperature and duration of the reaction depending on the reagents and reactor used.

[0138] The process of the invention advantageously makes it possible to obtain a mass yield of organochlorosilane SC of greater than 80%, preferably greater than 90%, preferably greater than 95%.

[0139] In the context of the present invention, the term "organochlorosilane" is understood to mean a compound of the following formula (A), (B) or (C):

[0140] R2SiCl2(A) R3SiCl(B) RSiCl3(C)

[0141] Wherein R, the same or different, is selected from:

[0142] -H,

[0143] - a linear or branched alkyl group containing 1 to 15 carbon atoms, preferably 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, preferably a methyl group;

[0144] - an aryl group containing 6 to 10 carbon atoms, preferably a phenyl group

[0145] -OH;

[0146] -alkenyl, in particular containing 2 to 6 carbon atoms, preferably vinyl;

[0147] - a linear or branched alkyl group containing 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, which is substituted by at least one fluorine atom, for example 1 to 10 fluorine atoms, for example (C1-C5)alkyl-CF3, which alkyl group is linear or branched;

[0148] -O-Alk, wherein Alk represents an alkyl group containing 1 to 15 carbon atoms, preferably 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, preferably methyl;

[0149] -(O-Alk) x , wherein Alk represents an alkyl group containing 1 to 15 carbon atoms, preferably 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, preferably a methyl group; and x represents an integer between 2 and 200;

[0150] - amino groups, in particular (Alk)-NH2 or (Alk)-NH-(Alk)-NH2, wherein Alk represents an alkyl group containing 1 to 5 carbon atoms;

[0151] -Cyclic amines, such as -(CH2) z -O-piperidine, wherein z represents an integer from 1 to 5, preferably 3; and the piperidine may in particular be substituted by one or more alkyl groups containing 1 to 3 carbon atoms, preferably methyl; preferably, the substituted piperidine is a group

[0152] Preferably, the organochlorosilanes of the present invention contain at most one hydrogen atom.

[0153] Preferably, in formula (A), (B) and (C), R, being the same or different, is selected from:

[0154] -H,

[0155] - a linear or branched alkyl group containing 1 to 15 carbon atoms, preferably 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, preferably a methyl group;

[0156] - an aryl group containing 6 to 10 carbon atoms, preferably a phenyl group

[0157] -OH;

[0158] -alkenyl, in particular containing 2 to 6 carbon atoms, preferably vinyl;

[0159] - a linear or branched alkyl group containing 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, which is substituted by at least one fluorine atom, for example 1 to 10 fluorine atoms, for example (C1-C5)alkyl-CF3, which alkyl group is linear or branched;

[0160] Preferably, the organochlorosilanes of the present invention contain at most one hydrogen atom.

[0161] Preferably, the preferred organochlorosilanes of the present invention are those of formula (I) or (II).

[0162] Without wishing to be bound by any theory:

[0163] The organopolysiloxane of formula (I) is derived from the D unit of organosilicon S, so R of formula (I) depends on the D unit of organosilicon S;

[0164] The organopolysiloxane of formula (II) is derived from the M unit of the organosilicon S, so that R of formula (II) depends on the M unit of the organosilicon S;

[0165] The organopolysiloxane of formula (III) is derived from the T units of organosilicon S, so R of formula (III) depends on the T units of organosilicon S.

[0166] Particularly advantageously, the organochlorosilanes obtained by the process of the invention can be used directly in other industrial processes as a source of raw materials and then hydrolyzed and condensed to produce new oils, resins or gums.

[0167] The present application also relates to the use of the organochlorosilane obtained by the process of the present invention for preparing silicones, for example for preparing silicone oils, resins or glues.

[0168] The present application also relates to a method for preparing silicone, in particular oil, resin or glue, comprising the following steps:

[0169] 1) implementing the method for preparing organochlorosilane according to the present invention;

[0170] 2) Preparation of organosilicon, in particular oil and resin or gum, from the organochlorosilane obtained in step 1).

[0171] Step 2) can be carried out in particular by condensation hydrolysis. DETAILED DESCRIPTION

[0172] The present application will now be described with the aid of the following examples.

[0173] Example :

[0174] Silicone used in the examples :

[0175] In the following, Me = methyl, Vi = vinyl

[0176] Silicone S1: Viscosity: 100mPa.s Silicone S2: Viscosity: 1000mPa.s Silicone S3: Viscosity: 100mPa.s Silicone S4: Viscosity: 1500mPa.s Silicone S5: Viscosity: 10 000mPa.s Silicone S6: Viscosity: 100mPa.s Silicone S7: Viscosity: 14000mPa.s Silicone S8:

[0177] Silicone S9: Viscosity: 60 000mPa.s

[0178] Silicone S10:

[0179] Silicone S11: Silicone rubber

[0180]

[0181] Silicone S12: Silicone nipple pad (commercially available product, composition unknown)

[0182] Silicone S13: Silicone cake mold (commercially available product, composition unknown)

[0183] Silicone S14: Silicone sheet (commercially available product, composition unknown)

[0184] Silicone S15: Silicone tube (commercially available product, composition unknown)

[0185] Silicone S16: EVC A

[0186] Silicone S17: EVC B

[0187] Silicone S18: RTV1

[0188] Silicone S19: RTV2

[0189] Silicone S20: Fluorinated silicone oil (Mn=14000) (CAS 63148-56-1)

[0190]

[0191] Example 1: General solution for discontinuous mode

[0192] In a flask (10 mL) introduce organosilicon S and metal chloride CM. Add metal salt SM or metal salt solution and heat the reaction medium (temperature 40 ° C) for 30 minutes. Cool the reaction medium to ambient temperature (about 25 ° C) and introduce 1,3,5-trimethylbenzene (240 mg) (1,3,5-trimethylbenzene is an internal standard for detecting the amount of organochlorosilane in the desired product). Take a sample and pass it 1 HNMR and 29 The analysis was performed by Si NMR. The molar yields of the compound of formula (I) and the compound of formula (II) were determined relative to the number of moles of the units D and M of the organosilicon S, respectively.

[0193] Example 2: Effect of Catalyst on the Method of the Invention

[0194] Organosilicon S1 (300 mg, 4 mmol Me2SiO units) and BCl3 were prepared in 1 M (3 mL, 9 mmol Cl2) dichloromethane.- , 350 mg BCl3) as metal chloride was used to carry out the protocol of Example 1. The metal salts (SM), temperature and duration of the reaction are mentioned in Table 1 below.

[0195]

[0196]

[0197] The process according to the invention can be carried out using different metal salts while providing good yields.

[0198] Example 3: Effect of chlorine source on the method of the present invention

[0199] The protocol of Example 1 was carried out using organosilicon S1 (300 mg, 4 mmol SiMe2O units) and GaCl3 as metal salt (4 mg, 0.5 mol % relative to the moles of Si-O). The metal chlorides, temperature and duration of the reaction are mentioned in Table 2 below.

[0200]

[0201] The process of the present invention can be carried out using different chlorine sources while providing good yields.

[0202] Example 4: Effect of silicone on the method of the present invention

[0203] The protocol of Example 1 was carried out using different organosilicones mentioned in Table 3 below, GaCl3 as metal salt (0.5 mol%, 4 mg), BCl3 as metal chloride in toluene or dichloromethane solvent 1M (3 mL, except for S10: 6 ml). The process was carried out at 40°C.

[0204] The silicones, temperature and duration of the reaction are mentioned in Table 3 below.

[0205]

[0206] The results in Table 3 show that the method of the present invention is general and can be used for all types of silicones, including silicone blends as well as silicones containing fillers and even used silicones.

Claims

1. Process for preparing organochlorosilanes CS by reacting at least one organosilicon S with a metal or metalloid chloride CM in the presence of at least one metal salt catalyst SM, the metal or metalloid chloride CM being different from the metal salt SM.

2. The process according to claim 1, wherein the metal or metalloid chloride CM is selected from metalloid chlorides, transition metal chlorides, alkaline earth metal chlorides, alone or as a mixture.

3. The process according to claim 1 or 2, wherein the metal or metalloid chloride CM is selected from metal chlorides of the formula M'Clz, wherein M' represents B, Al, Ti, Zr, Mg, Zn, Ca, Sb, Ge, Si or Cu, preferably B, Al, Ti, Zr, Mg, Ca, Zn, preferably B, Al, Mg, Zn, Ca, preferably B, Al; z represents an integer depending on the valence of the metal M′, for example z represents 3, 4 or 5.

4. The process according to any one of claims 1 to 3, wherein the metal or metalloid chloride CM is preferably selected from BCl3, AlCl3, TiCl4, ZrCl4, MgCl2, ZnCl2, CuCl2, CaCl2, GeCl4, SiCl4, SbCl5, alone or as a mixture, preferably BCl3, AlCl3, MgCl2, ZnCl2, CaCl2, more preferably AlCl3, BCl3, preferably BCl3.

5. The method according to any one of claims 1 to 4, wherein the metal salt is selected from the group consisting of: m A compound wherein: M represents Ga, Ge, Al, In or Fe, preferably Ga, Al or Fe, X represents Cl, Br, I, F, OTf, BF4, SbF6 m represents an integer depending on the metal M, and preferably, m represents 2, 3 or 4.

6. The method according to any one of claims 1 to 5, wherein the metal salt is selected from GaCl3, FeCl2, FeCl3, InCl3, AlCl3, GeCl4, preferably FeCl3, FeCl2, AlCl3, GaCl3, InCl3.

7. The process according to any one of claims 1 to 6, wherein the amount of metal salt SM used in the process of the invention is 0.01-10 mol %, preferably 0.01-5 mol %, for example 0.1-2 mol %, relative to the molar number of Si-O.

8. The process according to any one of claims 1 to 7, wherein the reaction is carried out at a temperature of 0-200°C, preferably 0-150°C, preferably 20-130°C, more preferably 30-110°C.

9. The process according to any one of claims 1 to 8, wherein the Cl / Si—O molar ratio is between 1 and 3, preferably between 2 and 3, such as between 2 and 2.5, such as 2.

10. The process according to any one of claims 1 to 9, wherein the amount of metal or metalloid chloride CM used in the process is at least 50 mol %, preferably 50-800 mol %, preferably 50-300 mol %, for example 50-200 mol %, relative to the moles of Si—O.

11. A method for preparing silicone, in particular silicone oil, resin or glue, comprising the following steps: 1) Implementing the method for preparing organochlorosilane according to any one of claims 1 to 10; 2) Preparing organic silicon, especially organic silicon oil, resin or glue, from the organic chlorosilane obtained in step 1).

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