Method for producing organopolysiloxane having unsaturated groups

Abstract

The method for producing an organopolysiloxane having an unsaturated group of the present invention comprises, in a first step, reacting a compound represented by the formula (I): R a Q b SiO (4-a-b) / 2 Organopolysiloxane (A) containing units of formula (II): R 2 d (OR 1 ) f SiO (4-d-f) / 2 and optionally an organopolysiloxane (B) containing units of the general formula (III): 3-(e+g) / 2 R 3 e Q 1 g Si-Y(SiR 3 e Q 1 g O 3-(e+g) / 2)c and a basic catalyst (D) selected from the group consisting of alkali metal hydroxides, alkali metal alkoxides, and alkali metal siloxanolates; in a second step, the mixture obtained in the first step is reacted at 80 to 170°C; and in a third step, the reaction mixture obtained in the second step is neutralized with a carboxylic acid derivative (E) having at least 4 carbon atoms.

Description

[Technical field]

[0001] The present invention relates to a method for preparing organopolysiloxanes containing unsaturated groups by base-catalyzed equilibration or condensation. [Background technology]

[0002] The preparation of functional organopolysiloxanes via equilibration with alkali catalysts has been described in many publications and in the prior art. For example, catalysts such as alkali metal, ammonium and phosphonium hydroxides or sil(oxo)anolates are known (Polym. Sci., Part C No. 16, 669-677 (1967); Makromol. Chem., Macromol. Symp. 6, 67-80 (1986); Polym. Prepr. 29 (1), 123-125 (1988), etc.).

[0003] EP 628589 B1 describes the use of strontium or barium hydroxide in combination with sodium borate or sodium phosphate. However, the process described therein has the disadvantage that the metal hydroxides must be neutralized with acid at the end of the reaction in order to be inactivated. This leads to undesirable turbidity and precipitation in the form of salts.

[0004] EP 2055777 describes a multi-step process for preparing organopolysiloxanes comprising aminoalkyl groups, in which a basic catalyst can be deactivated with a long-chain carboxylic acid. Summary of the Invention

[0005] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide an advantageous method for the preparation of unsaturated organopolysiloxanes. That object is achieved by the present invention.

[0006] The present invention relates to In the first step, An organopolysiloxane (A) comprising units of formula (I), R a Q b SiO (4-a-b) / 2 (I) (In the formula, R is the same or different, and is a monovalent saturated hydrocarbon group having 1 to 19 carbon atoms, which is optionally substituted with a fluorine, chlorine or bromine atom; Q is an unsaturated hydrocarbon group, which may be the same or different, and may contain aromatic and / or aliphatic double bonds; a is 0, 1, 2 or 3, preferably 1, 2 or 3; b is 0, 1, 2 or 3, preferably 0 or 1; provided that the sum of a+b is ≦3, and the organopolysiloxane (A) has at least one radical Q. an organopolysiloxane (B) comprising units of formula (II), R 2 d (OR 1 ) f SiO (4-d-f) / 2 (II) (In the formula, R 2 are the same or different, and are monovalent saturated hydrocarbon groups having 1 to 18 carbon atoms, which are optionally substituted with fluorine, chlorine or bromine atoms; R 1 are the same or different alkyl groups having 1 to 4 carbon atoms, which alkyl groups are optionally substituted with hydrogen or oxygen atoms; d is 0, 1, 2 or 3, preferably 2; f is 0, 1, 2 or 3, preferably 0 or 1; However, the sum of d+f is ≦3.) Optionally, an organopolysiloxane compound (C) containing at least one molecular structural unit of general formula (III), and O 3-(e+g) / 2 R 3 e Q1 g Si-Y(SiR 3 e Q 1 g O 3-(e+g) / 2)c (III) (In the formula, R 3 are the same or different, and are monovalent saturated hydrocarbon groups having 1 to 18 carbon atoms, which may be substituted with a fluorine atom, a chlorine atom, or a bromine atom; Q1 are the same or different, unsaturated hydrocarbon groups which may contain aromatic and / or aliphatic double bonds; Y is a divalent to dodecavalent organic group having 1 to 30 carbon atoms, which may contain one or more oxygen atoms; e is 0 or 1; c is an integer from 1 to 11; g is 0 or 1, However, the sum of e+g is ≦2.) A basic catalyst (D) selected from the group consisting of alkali metal hydroxides, alkali metal alkoxides and alkali metal siloxanolates; Mix the In the second step, The mixture obtained in the first step is reacted at 80 to 170°C, In the third step, neutralizing the reaction mixture obtained in the second step with a carboxylic acid derivative (E) having at least 4 carbon atoms; The present invention relates to a method for producing an organopolysiloxane having an unsaturated group. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] In the context of the present invention, the term "organopolysiloxane" is intended to include polymeric, oligomeric, and dimeric siloxanes.

[0008] Hydrocarbon groups R, R 2 and R 3Examples of are, each independently, alkyl radicals such as methyl, ethyl, n-propyl, isopropyl, 1-n-butyl, 2-n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl radicals, hexyl radicals such as n-hexyl radical, heptyl radicals such as n-heptyl radical, octyl radicals such as n-octyl radical, isooctyl radicals such as 2,2,4-trimethylpentyl radical, nonyl radicals such as n-nonyl radical, decyl radicals such as n-decyl radical, dodecyl radicals such as n-dodecyl radical, octadecyl radicals such as n-octadecyl radical, and the like; and cycloalkyl radicals such as cyclopentyl, cyclohexyl, cycloheptyl, methylcyclohexyl, and the like.

[0009] Substituted hydrocarbon groups R, R 2 and R 3 Examples of are, each independently, haloalkyl radicals such as the 2,2,2',2',2'-hexafluoroisopropyl radical, the 3,3,3-trifluoro-n-propyl radical, the heptafluoroisopropyl radical, and haloaryl radicals such as o-, m- and p-chlorophenyl radicals.

[0010] Preferably, the groups R, R 2 and R 3 are each independently a monovalent hydrocarbon group having 1 to 6 carbon atoms, and are particularly preferably a methyl group.

[0011] Examples of unsaturated hydrocarbon groups Q and Q1 are each independently alkenyl radicals such as vinyl, allyl, 5-hexen-1-yl, E-4-hexen-1-yl, Z-4-hexen-1-yl, 2-(3-cyclohexenyl)ethyl and cyclododeca-4,8-dienyl radicals.

[0012] The radicals Q and Q1 are each independently preferably a group which contains an aliphatic double bond, particularly preferably a vinyl, allyl or 5-hexen-1-yl radical, in particular a vinyl radical.

[0013] The organopolysiloxane (A) used in the present invention is preferably a substantially linear, branched or cyclic siloxane, and the linear siloxane may have unsaturated groups at the ends and / or in the side chains.

[0014] The organopolysiloxanes (A) used according to the invention are particularly preferably compounds of the formula (IV): Q h R 3-h SiO(R 2 SiO) x (QRSiO) y SiR 3-h Q h (IV) (In the formula, R and Q each have the above definition; h is 0, 1, 2 or 3, preferably 1; x is 0 or an integer from 1 to 500; y is 0 or an integer from 1 to 50, preferably 0; provided that the compound of formula (IV) has at least one radical Q). It is.

[0015] Although not shown in formula (IV), other siloxane units may be present in addition to the units shown in formula (IV) as a result of preparation, such as the siloxane unit -SiO 3 / 2 may be present as an impurity, preferably in an amount of up to 10 mol %.

[0016] Examples of organopolysiloxanes (A) which can be used according to the invention are ViMe2SiO(Me2SiO) 10~200 SiMe2Vi, Allyl(Me2)SiO(Me2SiO) 10~200 Si(Me2)allyl, ViEtSiO(Et2SiO) 10~200 SiEt2Vi, and (5-Hexene-1-yl)Me2SiO(Me2SiO) 10~200 SiMe2(5-hexen-1-yl), Preferably, ViMe2SiO(Me2SiO) 10~100 SiMe2Vi, Allyl(Me2)SiO(Me2SiO) 10~100 Si(Me2)allyl, ViEt2SiO(Et2SiO) 10~100 SiEt2Vi, or (5-Hexen-1-yl)Me2SiO(Me2SiO) 10~100 SiMe2 (5-hexen-1-yl), Particularly preferably, ViMe2SiO(Me2SiO) 10~20 SiMe2Vi, Allyl(Me2)SiO(Me2SiO) 10~20 Si(Me2)allyl, ViEt2SiO(Et2SiO) 10~20 SiEt2Vi, or (5-Hexen-1-yl)Me2SiO(Me2SiO) 10~20 SiMe2 (5-hexen-1-yl). In the above formula, Me is a methyl radical, Et is an ethyl radical, allyl is an allyl group, and Vi is a vinyl group.

[0017] The organopolysiloxane (A) used in the present invention preferably has a viscosity at 25°C of 5 to 100,000 mPa·s, and more preferably 10 to 100 mPa·s.

[0018] Component (A) used in the present invention is either commercially available or can be prepared by standard chemical synthesis.

[0019] In the process according to the invention, the organopolysiloxane (A) is preferably used in an amount of 1.0 to 40% by weight, preferably 10 to 30% by weight, in each case based on the total weight of the organosiloxane compounds (A), (B) and optionally (C).

[0020] Hydrocarbon group R, which may be interrupted by oxygen atoms 1 Examples include alkyl radicals such as methyl, ethyl, n-propyl, isopropyl, 1-n-butyl, 2-n-butyl, isobutyl and tert-butyl radicals, as well as methoxyethyl and ethoxyethyl radicals.

[0021] base R 1 is preferably a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms, and particularly preferably a hydrogen atom or a methyl group.

[0022] The organopolysiloxanes (B) used in the process according to the invention may be substantially linear, branched or cyclic, preferably substantially linear or cyclic.

[0023] It is also possible to use mixtures of essentially linear and cyclic organopolysiloxanes as component (B).

[0024] Preferably, the cyclic organopolysiloxane (B) has from 3 to 20 silicon atoms, particularly preferably from 3 to 8 silicon atoms, in particular from 4 to 6 silicon atoms.

[0025] If the organopolysiloxanes (B) used in the process according to the invention are cyclic organopolysiloxanes, they preferably contain the group (OR 1 ), where R 1 has the same definition as above.

[0026] The essentially linear organopolysiloxane (B) is preferably an organopolysiloxane of the general formula (V). (R1 O)R 2 2SiO(R 2 2SiO) z SiR2(OR 1 ) (V) (In the formula, R 2 and R 1 each having the above definition, z is an integer between 20 and 100.

[0027] Although not shown in formula (V), other siloxane units may be present in addition to the units shown in formula (V) as a result of preparation, such as the siloxane unit -SiO 3 / 2 may be present as an impurity, preferably in an amount of up to 10 mol %.

[0028] Examples of organopolysiloxanes (B) which can be used according to the invention are OHMe2SiO(Me2SiO) 10~500 SiMe2OH, OHEt2SiO(Et2Si) 10~500 SiEtOH, and [Si(Me2)O ]3~20 and Preferably, OHMe2SiO(Me2SiO) 10~200 SiMe2OH, OHEt2SiO(Et2Si) 10~200 SiEtOH, or [Si(Me2)O] 3~10 and Particularly preferably, OHMe2SiO(Me2SiO) 10~100 SiMe2OH, OHEt2SiO(Et2Si) 10~100 SiEtOH, or [Si(Me2)O] 3~8 It is. In the above formula, Me is a methyl group and Et is an ethyl group.

[0029] The organopolysiloxane (B) used in the present invention preferably has a viscosity at 25°C of 1 to 100,000 mPa·s, more preferably 1 to 200 mPa·s at 25°C.

[0030] The component (B) used in the present invention is either commercially available or can be prepared by standard chemical synthesis.

[0031] In the process according to the invention, the organopolysiloxane (B) is preferably used in an amount of 30 to 99% by weight, preferably 70 to 95% by weight, in each case based on the total weight of the organosiloxane compounds (A), (B) and optionally (C).

[0032] The number of carbon atoms in the group Y divided by the valence of Y is preferably at most 10, preferably at most 5, particularly preferably at most 3.

[0033] The group Y is preferably a linked organic unit having 1 to 24 carbon atoms between 2 to 12 siloxanyl units (Si atoms). Y is preferably divalent, trivalent or tetravalent, particularly preferably divalent.

[0034] Examples of Y include a methylene group, a methine group, or a tetravalent carbon, a 1,1-ethanediyl group, a 1,2-ethanediyl group, a 1,4-butanediyl group, and a 1,3-butanediyl group.

[0035] When Y contains at least two carbon atoms, Y may be unsaturated, for example a -CH=CH- group (cis or trans), [ka] groups and -C≡C- groups.

[0036] The radical Y is particularly preferably an organic unit having up to 12 carbon atoms, particularly preferably having 2 carbon atoms. Examples of particularly preferred radicals Y are -CH2CH2-, -CH(CH3)-, -CH=CH-, -C(=CH2)- or -C≡C-.

[0037] Examples of the optionally used organopolysiloxane compounds (C) are substantially linear, branched, crosslinked or cyclic siloxanes.

[0038] The optionally used organopolysiloxane compound (C) is preferably an organosiloxane of the formula: [ka] [ka] [ka] [ka] [ka] or [ka]

[0039] The organopolysiloxane (C) optionally used in the present invention preferably has a viscosity at 25°C of 1 to 1000 mPa·s, more preferably 1 to 200 mPa·s at 25°C.

[0040] The organopolysiloxane (C) optionally used in the present invention has an iodine value at 25°C of preferably 20 to 200 Pa·s, more preferably 50 to 150 mPa·s.

[0041] The iodine value is the amount of iodine consumed in addition to aliphatic multiple bonds, expressed in grams per 100 g of material analyzed.

[0042] If an organosiloxane compound (C) is used in the process according to the invention, the amount involved is preferably 1 to 20% by weight, more preferably 2 to 10% by weight, in each case based on the total weight of organosiloxane compounds (A), (B) and (C). Component (C) is preferably used in the process according to the invention.

[0043] The optional component (C) used in the present invention is a compound that can be prepared by standard chemical synthesis. For example, European Patent Application Publication No. 1917292 describes a compound of the general formula: 3-a / 2 R a Si-Y(SiR a O 3-a / 2 ) b (wherein R may be the same or different and is a monovalent SiC-bonded organic group having 1 to 30 carbon atoms, Y is a divalent to dodecavalent organic group having 1 to 30 carbon atoms and may contain one or more O atoms, a is 0 or 1, and b is an integer of 1 to 11.)

[0044] Preferred examples of alkali metal hydroxides (D) used in the process according to the invention are potassium hydroxide or sodium hydroxide, preferably potassium hydroxide.

[0045] Preferred examples of alkali metal alkoxides (D) used in the process according to the invention are sodium methoxide, sodium ethoxide, potassium methoxide or potassium ethoxide, particularly preferably sodium methoxide or potassium methoxide.

[0046] Preferred examples of alkali metal siloxanolates (D) used in the process according to the invention are sodium, potassium or lithium siloxanolates, particularly preferably sodium or potassium siloxanolates, in particular Na-O-[Si(Me)2-O]n -Si(Me)2-O-Na, Na-O-[Si(Me)2-O] n -Si(Me)3, KO-[Si(Me)2-O] n -Si(Me)2-OK, and KO-[Si(Me)2-O] n -Si(Me)3, where Me is a methyl group and n is a number from 10 to 500.

[0047] In the process according to the invention, alkali metal hydroxides, in particular potassium hydroxide, are preferably used as catalysts (D).

[0048] In the process according to the invention, the catalyst (D) can be used in pure form or in a mixture with an organic solvent, the latter being preferred.

[0049] Particularly preferably, in the process according to the invention, the catalyst (D) is used in a mixture with an alcohol, preferably methanol, preferably in the case of KOH, a 20% by weight mixture in methanol, preferably in the case of sodium methoxide, a 30% by weight mixture in methanol.

[0050] In the process according to the invention, the catalyst (D) is preferably used in an amount of 1 to 1000 ppm by weight, preferably 10 to 400 ppm by weight and particularly preferably 30 to 200 ppm by weight, in each case calculated as pure substance and calculated based on the total weight of the organosiloxane compounds (A) and (B) and, if desired, (C).

[0051] The basic catalyst (D) is deactivated at the end of the reaction according to the invention by using a neutralizing agent (E) which, together with the basic catalyst (D), preferably forms a neutralization product which is largely soluble in the siloxanes produced at 25° C. and 1013 hPa. In the context of the present invention, largely soluble means that the neutralization product formed is preferably at least 60% by weight, particularly preferably at least 80% by weight, and in particular completely soluble in the organopolysiloxanes produced.

[0052] The carboxylic acid derivatives (E) used according to the invention preferably have at least 8 carbon atoms.

[0053] Examples of such neutralizing agents (E) include long-chain carboxylic acids that are liquid at room temperature and normal pressure, for example, carbonate esters such as n-octanoic acid, 2-ethylhexanoic acid, n-nonanoic acid, 2-butyloctanoic acid, 2-butyldecanoic acid, 2-butyldodecanoic acid, 2-hexyldecanoic acid, 2-heptylundecanoic acid, 2-octyldodecanoic acid, 2-decyltetradecenoic acid, undecenoic acid, oleic acid, and propylene carbonate, and carboxylic acid anhydrides such as octenylsuccinic anhydride.

[0054] The neutralizing agent (E) used in the present invention is preferably 2-ethylhexanoic acid, 2-butyloctanoic acid, 2-hexyldecanoic acid or 2-octyldodecanoic acid, particularly preferably 2-butyloctanoic acid.

[0055] The amount of neutralizing agent (E) required depends on the amount of basic catalyst (D) used and is preferably 1 to 10 equivalents, preferably 1.2 to 5 equivalents, particularly preferably 1.5 to 2.5 equivalents, based on the catalyst (D) in a pure state.

[0056] The process according to the invention can be carried out in the presence or absence of an organic solvent (L), although the use of a solvent (L) is not preferred. Examples of suitable solvents (L) are alcohols such as methanol, ethanol, n-propanol, isopropanol; ethers such as dioxane, tetrahydrofuran, diethyl ether, diethylene glycol dimethyl ether; chlorinated hydrocarbons such as dichloromethane, trichloromethane, tetrachloromethane, 1,2-dichloroethane, trichloroethylene; hydrocarbons such as pentane, n-hexane, hexane isomer mixtures, heptane, octane, petroleum benzine, petroleum ether, benzene, toluene, xylene; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone; carbon disulfide, nitrobenzene, or mixtures thereof.

[0057] The term "solvent" does not imply that all reaction components must be dissolved therein. Reactions according to the invention can also be carried out in a suspension or emulsion of one or more of the reactants.

[0058] The components used in the process according to the invention may be one of each such component or else a mixture of at least two of the respective components.

[0059] In the first step of the process according to the invention, components (A), (B), optionally (C) and the basic catalyst (D) are mixed by any method, such as with a propeller agitator. The order in which the different components are mixed can be varied if desired, it being preferred to add the catalyst (D) to a mixture of components (A), (B) and optionally (C).

[0060] The first step of the method according to the invention is preferably carried out at the pressure of the surrounding atmosphere, ie about 900-1100 hPa.

[0061] The first step of the process according to the invention is preferably carried out at a temperature of 20 to 90°C, particularly preferably 20 to 85°C.

[0062] The first step of the process according to the invention is preferably carried out under a protective gas, such as nitrogen or argon.

[0063] In the second step of the process according to the invention, the temperature is preferably from 90 to 150°C, particularly preferably from 110 to 140°C.

[0064] The second step of the process according to the invention is preferably carried out at a pressure of 20 to 1100 hPa, more preferably 100 to 1013 hPa, particularly preferably with a step of reducing the pressure intermittently or continuously in order to remove volatile compounds and / or air. In a preferred procedure for the second step according to the invention, the pressure is reduced intermittently or continuously to 30 to 500 hPa and then protective gas is introduced. In a further preferred process variant, when cyclic organosiloxanes are used as component (B), the second step is carried out at the pressure of the ambient atmosphere, i.e. 900 to 1100 hPa.

[0065] If a volatile compound is removed in the second step, the volatile compound is preferably water and / or alcohol.

[0066] The second step of the process according to the invention is preferably carried out for 10 to 240 minutes, particularly preferably for 30 to 180 minutes, which depends on the catalyst used, the amount of catalyst, the reaction temperature and the desired degree of equilibration or degree of condensation and can be adjusted according to the procedure.

[0067] After the reaction has taken place, the reaction mixture is further treated in a third step according to the invention by adding a neutralizing agent (E).

[0068] The third step of the process according to the invention is preferably carried out at a temperature of 100 to 160°C, particularly preferably 120 to 150°C.

[0069] The third step of the method according to the invention is preferably carried out at the pressure of the surrounding atmosphere, ie about 1013 hPa.

[0070] The third step of the process according to the invention is preferably carried out under a protective gas, such as nitrogen or argon.

[0071] A preferred variant of the method according to the invention is characterized in that: 1st step: The organopolysiloxane (A), the organopolysiloxane (B) and, if desired, the organopolysiloxane compound (C) are first charged at room temperature, and the catalyst (D) is weighed and mixed at a temperature of 20 to 90°C. Second step: The mixture obtained in the first step is reacted at a temperature of 90 to 150° C. and a pressure of 20 to 1100 hPa, and Third step: The reaction mixture obtained in the second step is neutralized with component (E) at a temperature of 100 to 160°C.

[0072] A particularly preferred variant of the method is characterized in that: 1st step: The organopolysiloxane (A), the cyclosiloxane (B) and, if desired, the organopolysiloxane compound (C) are first charged at room temperature, and the catalyst (D) is weighed and mixed at a temperature of 20 to 90°C. Second step: The mixture obtained in the first step is reacted at a temperature of 90 to 150° C. and a pressure of 20 to 1100 hPa, and Third step: The reaction mixture obtained in the second step is neutralized with component (E) at a temperature of 100 to 160°C.

[0073] A further preferred variant of the method is characterized in that: 1st step: The organopolysiloxane (A), the organopolysiloxane (B) and the organopolysiloxane compound (C) are first charged at room temperature, and the catalyst (D) is weighed at a temperature of 20 to 90°C and mixed; Second step: The mixture obtained in the first step is reacted at a temperature of 90 to 150° C. and a pressure of 20 to 1100 hPa, and Third step: The reaction mixture obtained in the second step is neutralized with component (E) at a temperature of 100 to 160°C.

[0074] The reaction mixture obtained in the third step can be treated by any method known to date, if desired. For example, volatile components, especially cycles, can be removed by distillation. When the reaction mixture is purified by distillation after the completion of the third step, the distillation is preferably carried out at a temperature of 140 to 170 ° C. and a pressure of 1 to 50 hPa.

[0075] The process according to the invention can be carried out batchwise, semi-continuously or fully continuously.

[0076] The process according to the invention advantageously provides a clear liquid at room temperature and ambient pressure that does not need to be filtered because most of the neutralization product of catalyst (D) and component (E) is dissolved in the siloxane matrix. The liquids produced according to the invention are preferably free of component (D).

[0077] The process of the present invention results in unsaturated organopolysiloxanes which may be substantially linear or branched, in which the unsaturated groups may be terminal and / or pendant. The siloxanes produced by the process of the present invention are preferably present as a mixture with the neutralization product of components (D) and (E), and optionally with an excess of component (E).

[0078] The viscosity of the organopolysiloxanes produced by the process according to the invention can vary within a wide range, the viscosity being preferably in the range from 10 to 100,000 mPa·s, particularly preferably from 50 to 1,000 mPa·s.

[0079] The iodine value of the organopolysiloxanes produced by the process according to the invention can vary within a wide range; the iodine value is preferably in the range of 1-100, particularly preferably 2-20.

[0080] The organopolysiloxane produced according to the present invention preferably exhibits a turbidity of 0 to 65 FTU, and particularly preferably 0 to 35 FTU.

[0081] The turbidity measurements in the present invention are based on the DIN EN 27027 standard. The stated turbidity values ​​are based on scattered light measured at an angle of 25 degrees. For the measurements, the sample is filled, preferably bubble-free, into a 250 ml glass flask (diameter: 68 mm, height: 115 mm) and measured at a wavelength of 650 nm using a Sigrist LabScat instrument. The results are given in units of FTU (Formazin Turbidity Units).

[0082] The organopolysiloxanes produced by the process according to the invention can be used for any purpose known to date, and can, if necessary, be mixed with inhibitors such as ethynylcyclohexanol or diallyl maleate or with anti-misting agents.

[0083] The method according to the invention has the advantage that it is very simple to implement.

[0084] The process according to the invention has the advantage that organopolysiloxanes containing unsaturated groups can be reproducibly prepared regardless of the silanol value of the reactants.

[0085] Furthermore, the process according to the invention has the advantage that a transparent product is obtained which is stable over time.

[0086] The process according to the invention has the advantage that by varying the stoichiometry the viscosity and the content of unsaturated groups in the product can be flexibly adjusted in a simple manner.

[0087] The process according to the invention has the advantage that it is economical since the compounds separated by distillation, such as cyclosiloxanes, can be reused. EXAMPLES

[0088] In the following examples, all amounts reported in parts and percentages are by weight unless otherwise specified. Unless otherwise specified, the following examples are carried out at ambient atmospheric pressure, i.e., about 1013 hPa, and at room temperature, i.e., about 23°C, or the temperature that occurs when the reactants are combined at room temperature without additional heating or cooling. All exemplified viscosity data are intended for a temperature of 25°C.

[0089] The viscosity measurements according to the present invention are carried out in accordance with DIN 51562 (Ubbelohde) and DIN EN ISO 2555 (Brookfield). Measurements in accordance with DIN 51562 are carried out at 25° C. and are expressed in mm 2 Measurements in accordance with DIN EN ISO 2555 were made with a Brookfield DV2T Extra viscometer at 25 °C and are expressed in mPa s.

[0090] [How to prepare star polymer (C1)] A mixture of 109 g of redistilled 1,2-bis(methyldichlorosilyl)ethane (1.7 eq. Cl) and 820 g of vinyldimethylchlorosilane (6.8 eq. Cl) is cooled to 10 ° C. Simultaneously cooling with stirring, a total of 1.7 L of 5% HCl solution is metered in within about 80 minutes, maintaining the temperature of the reaction mixture at 10-20 ° C. The mixture is then stirred vigorously for 30 minutes and the phases are separated. The siloxane phase is washed 4 times with 1 L of water each time, neutralized with 0.5 l of 5% NaHCO3 solution and washed again with 1 L of water. Volatile hydrolysis products are removed in a vacuum up to 80 ° C (mainly divinyltetramethyldisiloxane). 149.8 g of a clear liquid is obtained as a residue, with a viscosity of 7.2 mm 2 / s (25 °C), the iodine value is 169.6, and there is exactly one C=C double bond per 149.8 g. The product consists of about 90% of the 1,2-bis(methyldichlorosilyl)ethane used in hydrolyzed form.

[0091] [Example 1] From the star polymer (C1) prepared above, having an iodine value of 169.6, a branched vinyl polymer is prepared by equilibration with two linear siloxanes. For this purpose, 32.5 g of star polymer (C1) is mixed with 25 mm 2 177.7 g of an α,ω-divinyl-terminated dimethylpolysiloxane having a viscosity of 70 mm 2 596.9 g of α,ω-dihydroxy-terminated dimethylpolysiloxane with 1.0 g / s and 0.04 g of KOH are mixed, concentrated and equilibrated at 140 °C and 200 hPa pressure. After 2 hours, the catalyst is deactivated with 0.3 g of 2-butyloctanoic acid at a temperature of 140 °C and a pressure of 1013 hPa. The crude product is liberated from the volatile components octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane and dodecamethylcyclohexasiloxane at 140 °C and 10 hPa pressure. This gives a 210 mm viscosity. 2 The resulting product is a colorless, transparent silicone oil with an iodine value of 10.3 and a turbidity of 0.72 FTU.

[0092] [Example 2] From the star polymer (C1) prepared above, having an iodine value of 169.6, a branched vinyl polymer is prepared by equilibration with one linear siloxane and one cyclic siloxane. For this purpose, 32.5 g of star polymer (C1) is mixed with 25 mm 2 177.7 g of α,ω-divinyl-terminated dimethylpolysiloxane with a viscosity of 215 mm / s and an iodine value of 25.0, 596.9 g of a mixture of octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane (weight ratio of D4 to D5 25 to 75) and 0.04 g of KOH are added and equilibrated at 140 °C and a pressure of 1013 hPa. After 2 hours, the catalyst is deactivated with 0.3 g of 2-butyloctanoic acid at a temperature of 140 °C and a pressure of 1013 hPa. The crude product is liberated from the volatile components octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane and dodecamethylcyclohexasiloxane at 140 °C and a pressure of 10 hPa. This gives a viscosity of 215 mm 2The resulting product is a colorless, transparent silicone oil with an iodine value of 10.2 and a turbidity of 1.08 FTU.

[0093] [Example 3] The α,ω-divinyl-terminated dimethylpolysiloxane is prepared from α,ω-divinyl-terminated dimethylpolysiloxane by equilibration with α,ω-dihydroxy-terminated dimethylpolysiloxane. For this purpose, 25 mm 2 56.1 g of an α,ω-divinyl-terminated dimethylpolysiloxane having a viscosity of 1.0 g / s and an iodine value of 25.0 was poured into a 70 mm 2 The mixture is mixed with 165.8 g of α,ω-dihydroxy-terminated dimethylpolysiloxane having a viscosity of 190 mm / s and condensed and equilibrated at 140 °C and a pressure of 200 hPa under catalysis with 0.010 g of KOH. After 2 hours, the catalyst is deactivated with 0.088 g of 2-butyloctanoic acid at a temperature of 140 °C and a pressure of 1013 hPa. The crude product is freed from volatile components at 140 °C and 10 hPa. This gives a viscosity of 190 mm / s. 2 The resulting product is a colorless, transparent silicone oil with an iodine value of 6.9 and a turbidity of 0.98 FTU.

Claims

1. A method for producing an organopolysiloxane having an unsaturated group, comprising: In the first step, An organopolysiloxane (A) containing units of formula (I), R ａ Q ｂ SiO （４－ａ－ｂ）／２ (I) (wherein, R is a monovalent saturated hydrocarbon group having 1 to 19 carbon atoms, which may be the same or different, and the saturated hydrocarbon group may optionally be substituted with a fluorine, chlorine or bromine atom, Q is an unsaturated hydrocarbon group which may be the same or different and may contain an aromatic and / or aliphatic double bond, a is 0, 1, 2 or 3, b is 0, 1, 2 or 3, provided that the sum of a + b is ≦ 3, and the organopolysiloxane (A) has at least one radical Q.) An organopolysiloxane (B) containing units of formula (II), R ２ ｄ (OR １ ) ｆ SiO （４－ｄ－ｆ）／２ (II) (wherein, R ２ is a monovalent saturated hydrocarbon group having 1 to 18 carbon atoms, which may be the same or different, and the saturated hydrocarbon group may optionally be substituted with fluorine, chlorine or bromine atoms. R １ which may be the same or different and is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, d is 0, 1, 2 or 3, f is 0, 1, 2 or 3, provided that the sum of d + f is ≦ 3.) An organopolysiloxane compound (C) containing at least one molecular structural unit of general formula (III), O ３－（ｅ＋ｇ）／２ R ３ ｅ Q １ ｇ Si - Y(SiR ３ ｅ Q １ ｇ O ３－（ｅ＋ｇ）／２ ) ｃ (III) (wherein, R ３ is a monovalent saturated hydrocarbon group having 1 to 18 carbon atoms, which may be the same or different, and the saturated hydrocarbon group may be substituted with a fluorine atom, a chlorine atom or a bromine atom. Q １ is an unsaturated hydrocarbon group which may be the same or different and may contain aromatic and / or aliphatic double bonds, Y is a divalent to dodecavalent organic group having 1 to 30 carbon atoms, and the organic group may contain one or more oxygen atoms, e is 0 or 1, c is an integer from 1 to 11, g is 0 or 1, provided that the sum of e + g is ≦ 2.), and A basic catalyst (D) selected from the group consisting of alkali metal hydroxides, alkali metal alkoxides and alkali metal siloxanolates, are mixed, In the second step, The mixture obtained in the first step is reacted at 80 to 170 °C, In the third step, The reaction mixture obtained in the second step is neutralized with a carboxylic acid derivative (E) having at least 4 carbon atoms, method.

2. The method according to claim 1, wherein the organopolysiloxane (A) is used in an amount of 1.0 to 40% by weight based on the total weight of the organopolysiloxane compounds (A), (B) and (C).

3. The method according to claim 1 or 2, wherein the organopolysiloxane (B) is used in an amount of 30 to 99% by weight based on the total weight of the organopolysiloxane compounds (A), (B) and (C).

4. The method according to any one of claims 1 to 3, wherein an alkali metal hydroxide is used as the catalyst (D).

5. The method according to any one of claims 1 to 4, wherein the carboxylic acid derivative (E) used has at least 8 carbon atoms.

6. The method according to any one of claims 1 to 5, wherein the second step is carried out at a pressure of 20 to 1100 hPa.

7. In the first step, organopolysiloxane (A), organopolysiloxane (B) and organopolysiloxane compound (C) are initially charged at room temperature, and the catalyst (D) is weighed and mixed at a temperature of 20 to 90 °C. In the second step, the mixture obtained in the first step is reacted at a temperature of 90 to 150 °C and a pressure of 20 to 1100 hPa, and In the third step, the reaction mixture obtained in the second step is neutralized with component (E) at a temperature of 100 to 160 °C. The method according to any one of claims 1 to 6.

8. The reaction mixture after completion of the third step is worked up by distillation, and the distillation is carried out at a temperature of 140 to 170 °C and a pressure of 1 to 50 hPa. The method according to any one of claims 1 to 7.

9. The method according to any one of claims 1 to 8, wherein the resulting product has a turbidity of 0 to 65 FTU.

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