DE102011086866A1 - Preparing composition containing olefinically functionalized siloxane oligomers, useful e.g. as adhesive, comprises reacting composition containing olefinically functionalized siloxane oligomers having chlorine content with reducing agent - Google Patents

Abstract

Preparing a composition containing olefinically functionalized siloxane oligomers comprises reacting a composition containing olefinically functionalized siloxane oligomers having a chlorine content with a reducing agent.

Description

The invention relates to a process for the preparation of compositions comprising olefinically functionalized siloxane oligomers and mixtures thereof, wherein the compositions are substantially free of chlorine by contacting compositions comprising olefinically functionalized siloxane oligomers containing chlorine with a reducing agent. The present invention relates to a process for the preparation of chloride-free compositions of olefinically functionalized siloxane oligomers derived from olefinically-functionalized alkoxysilanes, which may be present as a mixture of olefinically functionalized siloxane oligomers having at most one olefinic radical per silicon atom and which are substantially chlorine-free.

It has long been known to use mixtures of chain and cyclic siloxane oligomers in the production of thermoplastics and elastomers. In the meantime, however, efforts are increasingly being made to work as low as possible on VOCs, for example in the crosslinking of thermoplastics and elastomers, in particular in the production of cables (VOCs - "Volatile Organic Compounds").

It is also known to react vinyltriethoxysilane, optionally in mixtures with alkyltriethoxysilanes and / or tetraethoxysilane, by acidic HCl-catalyzed hydrolysis and condensation in an alcohol in the presence of a calculated amount of water. Subsequently, alcohol is separated. The acid used remains in the product or, in the case of hydro- or hydrogen chloride (HCl), has to be removed again from the crude products produced after the reaction of the organofunctional alkoxysilanes in order not to contribute to a corrosion of the metallic surfaces of the processing machines. This is done by distillation of Siloxanrohprodukte.

In addition, silane systems are finding increasing interest, which contain fewer and fewer organic solvents and are therefore more environmentally friendly. For this reason, the trend is to provide precondensed VOC poorer silane systems, which then have to be stabilized because they still contain the catalyst or from which the catalyst must be separated consuming.

EP 0 518 057 B1 discloses a process for preparing mixtures of chain and cyclic siloxane oligomers. According to Examples 1 and 6, the respective product mixtures are prepared by hydrolysis and condensation of vinyltrialkoxysilanes or a mixture of vinyl and alkyltrialkoxysilanes, wherein per mole of Si silane used 0.63 mol of water for the hydrolysis and condensation are used. In addition, the HCl catalyst can not be completely separated by the method disclosed therein and a residual corrosive level of from about 50 to about 230 ppm HCl remains even in products that are distilled in accordance with the disclosed process.

Upon access of moisture or by progressive condensation due to the presence of HCl in the oligomer mixture, alcohol may be released. If such a release of alcohol during storage of the oligomer mixture, this usually leads to an undesirable decrease in the flash point. For this reason, a product must be in accordance with EP 0 518 057 B1 are already purified by distillation in the course of work-up in an energy-intensive and expensive manner under vacuum in order to reduce the HCl content. Use said oligomer mixtures as crosslinking agents for thermoplastic polyolefins by grafting and hydrolytic condensation.

CN 100343311 C describes silanoligomers obtained by catalytic hydrolysis and condensation of vinyltrimethoxysilane. The use of metal salt catalysts, such as copper hydroxide, in combination with acids is mandatory. The separation of the catalysts is complex and it is to be expected that catalyst residues or neutralization products remain in the product and adversely affect many applications. Thus, the separation of the acid by neutralization by means of calcium carbonate and filtration of the resulting calcium salt is sought here.

Siloxanes with high molecular weights in the range of 10,000 g / mol are in JP 10-298289 A wherein these are prepared by hydrolysis and precondensation or condensation of a vinyl- or phenyl-functional alkoxysilane in the presence of an acid catalyst and the catalyst is then removed with the aid of an anhydrous anionic ion exchanger from the product mixture. Such high molecular weight material can not be used in most applications due to high viscosities and low reactivity.

Organosiloxane oligomers having a multiplicity of possible functionalities, an average molecular weight in the range Mn = 350 to 2,500 g / mol and a polydispersity (D = Mw / Mn) of 1.0 to 1.3 are disclosed in US Pat JP 2004-099872 described. The preparation is carried out in the presence of a basic catalyst from a very dilute aqueous solution with a very low, economically not desirable space-time yield; thus 1 ml of product was isolated from 1 liter of solution.

It is an object of the present invention to provide a further possibility for producing substantially chlorine-free mixtures of purely olefinic siloxane oligomers, in particular based on alkenylalkoxysilanes, or substantially chlorine-free mixtures of olefinic and alkyl-functionalized siloxane oligomers, in particular based on alkenyl / alkylalkoxysilanes , The aim was also to provide a process that was as economical as possible, but at the same time flexible.

The objects according to the independent claims are solved, preferred embodiments are set forth in detail in the subclaims and in the description.

Surprisingly, it has been found that from compositions of olefinically functionalized siloxane oligomers, in particular mixtures thereof, having a content of chlorine, in particular having a content of Cl of greater than 80 mg / kg, preferably total chloride greater than 80 mg / kg and a content of hydrolyzable chloride of less than 75 mg / kg, in a simple and economical manner by contacting with a reducing agent, preferably with an inorganic reducing agent, compositions of olefinically functionalized siloxane oligomers, in particular mixtures thereof, can be obtained, which are substantially chlorine-free. In addition, the measure according to the invention can also be advantageously and flexibly combined with other process measures for reducing the Cl content in siloxane oligomer-containing compositions. By the method according to the invention in particular compositions of olefinically functionalized siloxane oligomers can be obtained which are substantially chlorine-free, the content of chlorine, in particular total chloride, in the total composition is less than or equal to 70 mg / kg to 0 mg / kg and in particular with hydrolyzable chloride less than or equal to 20 mg / kg.

The chlorine-free compositions according to the invention containing olefinically functionalized siloxane oligomers, in particular vinylsiloxane oligomers or vinyl / alkylsiloxane oligomers, in particular vinyl / propylsiloxane oligomers, require no further workup, unlike the known compositions of these oligomers. You do not have to be distilled consuming, like the products of the prior art. The prepared substantially chloride-free compositions containing olefinically functionalized siloxane oligomers exhibit the same or better performance as known but purified by distillation olefinic siloxane oligomers. It should be particularly emphasized that the process according to the invention is considerably more economical than a distillative purification. In addition, the composition can be isolated in greater yield.

The invention relates to a process for the preparation of compositions comprising olefinically functionalized siloxane oligomers, wherein the compositions are substantially chlorine-free by contacting a composition containing olefinically functionalized siloxane oligomers and having a chlorine content with a reducing agent, in particular with an inorganic reducing agent. Compositions of olefinically functionalized siloxane oligomers are understood as meaning, in particular, compositions of mixtures of these siloxane oligomers or of mixtures comprising olefinically functionalized siloxane oligomers and optionally further siloxane oligomers.

The invention thus provides a process for the preparation of compositions containing olefinically functionalized siloxane oligomers, wherein the compositions are substantially chlorine-free, by bringing a composition comprising olefinically functionalized siloxane oligomers and having a chlorine content in contact with a reducing agent, in particular with an organic and or inorganic reducing agent or with a reducing agent comprising organic and inorganic compounds. It is particularly preferred according to the inventive method, when the olefinically functionalized siloxane oligomers have at most one olefinic radical on the silicon atom, each silicon atom, the siloxane oligomer has at most one olefinic radical. The process according to the invention makes it possible to obtain a substantially chlorine-free composition of olefinically functionalized siloxane oligomers whose content of chlorine, in particular hydrolyzable chloride, in the overall composition is less than or equal to 70 mg / kg to 0 mg / kg.

• – die olefinisch funktionalisierten Siloxanoligomere Si-O-vernetzte Strukturelemente aufweisen, die kettenförmige, cyclische, vernetzte und/oder raumvernetzte Strukturen bilden, wobei mindestens eine Struktur in idealisierter Form der allgemeinen Formel I entspricht, (R¹O)[(R¹O)_1-x(R²)_xSi(A)O]_a[Si(Y)₂O]_c[Si(B)(R⁴)_y(OR³)_1-yO]_bR³ (I),
• – wobei die Strukturelemente aus Alkoxysilanen abgeleitet sind und
• – A in dem Strukturelement einem olefinischen Rest und
• – B in dem Strukturelement einem gesättigten Kohlenwasserstoff-Rest entsprechen,
• – Y entspricht OR³ oder in vernetzten und/oder raumvernetzten Strukturen unabhängig voneinander OR³ oder O_1/2,
• – wobei R¹ unabhängig voneinander einem linearen, verzweigten und/oder cyclischen Alkyl-Rest mit 1 bis 4 C-Atomen, und gegebenenfalls H entspricht,
• – R³ jeweils unabhängig voneinander einem linearen, verzweigten und/oder cyclischen Alkyl-Rest mit 1 bis 4 C-Atomen, und gegebenenfalls H entspricht, und R² und/oder R⁴ jeweils unabhängig einem linearen, verzweigten oder cyclischen Alkyl-Rest mit 1 bis 15 C-Atomen entsprechen,
• – a, b, c, x und y unabhängig ganzen Zahlen entsprechen mit 1 ≤ a, 0 ≤ b; 0 ≤ c, insbesondere ist c gleich 0 oder größer gleich 1, und insbesondere ist x unabhängig voneinander 0 oder 1, y ist unabhängig voneinander 0 oder 1, und (a + b + c) ≥ 2, insbesondere ist x gleich 0 oder y gleich 0, besonders bevorzugt sind x = 0 und y = 0.

According to one embodiment of the invention, the subject of the invention is a process for the preparation of essentially chlorine-free compositions containing olefinically functionalized Siloxane oligomers by contacting a composition containing olefinically functionalized siloxane oligomers and having a chlorine content with a reducing agent, the olefinically functionalized siloxane oligomers having at most one olefinic radical on the silicon atom, and wherein

• The olefinically functionalized siloxane oligomers have Si-O-crosslinked structural elements which form chain-like, cyclic, crosslinked and / or spatially crosslinked structures, at least one structure corresponding in an idealized form to the general formula I, (R ¹ O) [(R ¹ O) _1-x (R ²⁾ _x Si (A) O] _a [Si (Y) ₂ O] _c [Si (B) (R ⁴⁾ _y (OR ³⁾ _{1 -YO} ] _b R ³ (I),
• - Wherein the structural elements are derived from alkoxysilanes and
• A in the structural element is an olefinic radical and
• B in the structural element corresponds to a saturated hydrocarbon radical,
• Y is OR ³ or in crosslinked and / or spatially crosslinked structures independently of one another OR ³ or O _1/2 ,
• Wherein R ¹ independently of one another corresponds to a linear, branched and / or cyclic alkyl radical having 1 to 4 C atoms, and if appropriate H,
• - R ^{3 are} each independently a linear, branched and / or cyclic alkyl radical having 1 to 4 carbon atoms, and optionally H corresponds, and R ² and / or R ^{4 are} each independently a linear, branched or cyclic alkyl radical Correspond to 1 to 15 carbon atoms,
• - a, b, c, x and y independently correspond to integers with 1 ≤ a, 0 ≤ b; 0 ≤ c, in particular c is 0 or greater than 1, and in particular x is independently 0 or 1, y is independently 0 or 1, and (a + b + c) ≥ 2, in particular x is 0 or y equal to 0, more preferably x = 0 and y = 0.

• (ii) das in Gegenwart eines Hydrolyse- und/oder Kondensationskatalysators, insbesondere eines sauren Katalysators, besonders bevorzugt mit Chlorwasserstoff, bevorzugt die Alkoxysilane der Formeln II, III und/oder IV in Gegenwart eines sauren Katalysators, zumindest partiell hydrolysiert und kondensiert werden und, gegebenenfalls
• (iii) mit einem Alkoxysilan der Formel III B-Si(R⁴)_y(OR³)_3-y (III), wobei in Formel III B einem gesättigten Kohlenwasserstoff-Rest, R³ jeweils unabhängig voneinander einem linearen, verzweigten und/oder cyclischen Alkyl-Rest mit 1 bis 4 C-Atomen und R⁴ einem linearen, verzweigten oder cyclischen Alkyl-Rest mit 1 bis 15 C-Atomen entsprechen und y gleich 0 oder 1 ist, und/oder gegebenenfalls
• (iv) mit einem Tetraalkoxysilan der Formel IV Si(OR³)₄ (IV), wobei in Formel IV R³ jeweils unabhängig voneinander ein linearer, verzweigter und/oder cyclischer Alkyl-Rest mit 1 bis 4 C-Atomen ist,
• (v) mit einer definierten Menge Wasser, insbesondere von 0,5 bis 1,5 Mol Wasser je Mol Silizium-Atomen der Formeln II, III und/oder IV, gegebenenfalls in Gegenwart eines Lösemittels, vorzugsweise Alkohol, zu den Siloxanoligomeren umgesetzt werden und gegebenenfalls
• (vi) der Hydrolysealkohol und das gegebenenfalls vorliegende Lösemittel im Wesentlichen abgetrennt werden, vorzugsweise wird der Alkohol, insbesondere der Hydrolysealkohol und/oder der als Lösemittel zugesetzte Alkohol, im Wesentlichen vollständig entfernt, und insbesondere erfolgt (vii) ein Inkontaktbringen mit einem Reduktionsmittel, wobei es bevorzugt ist, dass – im olefinisch-funktionalisierten Alkoxysilan der allgemeinen Formel II, A-Si(R²)_x(OR¹)_3-x (II), A eine lineare, verzweigte oder cyclische Alkenyl- oder Cycloalkenyl-alkylen funktionelle Gruppe mit jeweils 2 bis 16 C-Atomen ist, bevorzugt mit 2 bis 8 C-Atomen, besonders bevorzugt eine Vinyl-, Allyl-, Butenyl-, Pentenyl-, Hexenyl-, Ethylhexenyl-, Heptenyl-, Octenyl-, Cyclohexenyl C1 bis C8-alkylen-, vorzugsweise Cyclohexenyl-2 ethylen-, wie 3´-Cyclohexenyl-2-ethylen-; und/oder Cyclohexadienyl-C1 bis C8-alkylen-, besonders vorzugsweise eine Cyclohexadienyl-2-ethylen-Gruppe, insbesondere ist x gleich 0, und R¹ unabhängig ein linearer, verzweigter und/oder cyclischer Alkyl-Rest mit 1 bis 4 C-Atomen, und/oder unabhängig – im Alkoxysilan der Formel III, B-Si(R⁴)_y(OR³)_3-y (III), der unsubstituierte Kohlenwasserstoff-Rest B ein linearer, verzweigter oder cyclischer Alkyl-Rest mit 1 bis 16 C-Atomen ist, bevorzugt mit 1 bis 7 C-Atomen, insbesondere mit x = 0 und y = 0.

According to an alternative or preceding embodiment of the invention, the invention provides a process for the preparation of compositions comprising olefinically functionalized siloxane oligomers, wherein the compositions are substantially chlorine-free, and a composition obtainable by this process, comprising a composition containing olefinically functionalized siloxane oligomers and containing is brought into contact with chlorine with a reducing agent, wherein the olefinically functionalized siloxane oligomers and / or olefinically functionalized siloxane oligomers of the formula I are derived from (i) at least one olefinically-functionalized alkoxysilane of the general formula II, A-Si (R ² ) _x (OR ¹ ) _3-x (II), wherein in formula II A is an olefinic radical, R ^{2 is} independently a linear, branched or cyclic alkyl radical having 1 to 15 C atoms and x is 0 or 1 and R ^{1 is} independently a linear, branched and / or cyclic alkyl radical Correspond to 1 to 4 carbon atoms,

• (ii) in the presence of a hydrolysis and / or condensation catalyst, in particular an acidic catalyst, particularly preferably with hydrogen chloride, preferably the alkoxysilanes of the formulas II, III and / or IV in the presence of an acidic catalyst, are at least partially hydrolyzed and condensed, and possibly
• (iii) with an alkoxysilane of formula III B-Si (R ⁴ ) _y (OR ³ ) _3-y (III), wherein in formula III B a saturated hydrocarbon radical, R ^{3 are} each independently a linear, branched and / or cyclic alkyl radical having 1 to 4 C-atoms and R ^{4 is} a linear, branched or cyclic alkyl radical having 1 to 15 C atoms correspond and y is 0 or 1, and / or optionally
• (iv) with a tetraalkoxysilane of formula IV Si (OR ³ ) ₄ (IV), in formula IV, R ³ is, independently of one another, a linear, branched and / or cyclic alkyl radical having 1 to 4 C atoms,
• (V) with a defined amount of water, in particular from 0.5 to 1.5 moles of water per mole of silicon atoms of the formulas II, III and / or IV, optionally in the presence of a solvent, preferably alcohol, are reacted to the siloxane oligomers, and possibly
• (vi) the hydrolysis alcohol and the optionally present solvent are essentially removed, preferably the alcohol, in particular the hydrolysis alcohol and / or the alcohol added as solvent, is substantially completely removed, and in particular (vii) contacting takes place with a reducing agent, it being preferred that: in the olefinically-functionalized alkoxysilane of the general formula II, A-Si (R ² ) _x (OR ¹ ) _3-x (II), A is a linear, branched or cyclic alkenyl or cycloalkenyl-alkylene functional group having in each case 2 to 16 C atoms, preferably having 2 to 8 C atoms, particularly preferably a vinyl, allyl, butenyl, pentenyl, hexenyl -, ethylhexenyl, heptenyl, octenyl, cyclohexenyl C1 to C8 alkylene, preferably cyclohexenyl-2 ethylene, such as 3'-cyclohexenyl-2-ethylene-; and / or cyclohexadienyl-C1 to C8-alkylene, particularly preferably a cyclohexadienyl-2-ethylene group, in particular x is 0, and R ^{1 is} independently a linear, branched and / or cyclic alkyl radical having 1 to 4 C- Atoms, and / or independently - in the alkoxysilane of the formula III, B-Si (R ⁴ ) _y (OR ³ ) _3-y (III), the unsubstituted hydrocarbon radical B is a linear, branched or cyclic alkyl radical having 1 to 16 C atoms, preferably having 1 to 7 C atoms, in particular having x = 0 and y = 0.

According to a preferred process variant, the alkoxysilanes of the formulas II, III and / or IV are at least partially hydrolyzed and condensed in the presence of an acidic catalyst, in particular with hydrogen chloride, and, preferably, the alcohol is substantially completely removed. Other suitable hydrolysis and / or condensation catalysts are customary acidic catalysts such as formic acid, acetic acid and other carboxylic acids or mineral acids known to those skilled in the art.

The invention particularly preferably relates to a process according to which a composition containing olefinically functionalized siloxane oligomers is obtained, which is substantially chlorine-free, preferably its content of chlorine, preferably hydrolyzable chloride, in particular in the total composition, less than or equal to 70 mg / kg to 0 mg / kg. According to an alternative, the content of chlorine with respect to the total composition, preferably total chloride, is preferably less than or equal to 70 mg / kg, optionally up to 0 mg / kg, in particular less than or equal to 60 mg / kg, preferably less than or equal to 50 mg / kg. more preferably less than or equal to 45 mg / kg, more preferably less than or equal to 40 mg / kg, preferably less than or equal to 35 mg / kg, further less than or equal to 20 mg / kg, more preferably less than or equal to 10 mg / kg, also preferably less than or equal to 5 mg / kg to 0.001 mg / kg, wherein in particular at the same time or alternatively, the content of hydrolyzable chloride is less than or equal to 40 mg / kg to 0.001 mg / kg, in particular less than or equal to 15 mg / kg, preferably less than or equal to 12 mg / kg, preferably less than or equal to 10 mg / kg; particularly preferably less than 8 mg / kg up to the detection limit or less than or equal to 3 mg / kg to 0 mg / kg, in particular in the composition.

The content of chlorine in the composition treated according to the invention in a substantially chlorine-free composition with respect to the total composition as hydrolyzable chloride may preferably be less than or equal to 60 mg / kg to 0 mg / kg, in particular less than or equal to 50 mg / kg, preferably less than or equal to 30 mg / kg, more preferably less than or equal to 15 mg / kg to 0 mg / kg, preferably less than or equal to 12 mg / kg, preferably less than or equal to 10 mg / kg, more preferably less than 4 mg / kg up to the detection limit or less than or equal to 3 mg / kg ,

The invention likewise provides a process in which a composition comprising olefinically functionalized siloxane oligomers and having a content of chlorine has a content of not completely alkoxylated siloxanes, in particular the composition has a content of olefinic siloxane oligomers, in particular of the formula I, with Si-Cl Residues, for example unreacted Si-Cl residues and / or free chlorides. Residues of Si-Cl may result from incompletely reacted chlorosilanes in the synthesis of the alkoxysilanes which are converted to siloxane oligomers.

It is particularly preferred if in the compositions olefinically functionalized siloxane oligomers siloxane oligomers have at most one olefinic radical per silicon atom.

All alkyl radicals; such as R ¹ , R ² , R ³ , R ⁴ ; with 1 to 4 C atoms, in particular of the formulas I, II, III and / or IV, in each case independently of one another, preferably methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl and / or 2-methylbutyl. The alkyl radicals R ² and / or R ^{4 may} each independently correspond to a linear, branched or cyclic alkyl radical having 1 to 15 C atoms.

According to particularly preferred embodiments, the olefinic radical A in formulas I and / or II corresponds to a nonhydrolyzable olefinic radical, in particular a linear, branched or cyclic, alkenyl- or cycloalkenyl-alkylene-functional group having in each case 2 to 16 C atoms, preferably 2 to 8 C atoms, preferably a vinyl, allyl, butenyl, such as 3-butenyl, pentenyl, hexenyl, ethylhexenyl, heptenyl, octenyl, cyclohexenyl-C1 to C8-alkylene, preferably cyclohexenyl-2 -ethylene, such as 3'-cyclohexenyl-2-ethylene and / or cyclohexadienyl-C1 to C8-alkylene, preferably cyclohexadienyl-2-ethylene group.

Also preferably, the unsubstituted hydrocarbon radical B can independently of formula I and / or III correspond to a linear, branched or cyclic alkyl radical having 1 to 16 C atoms, in particular a methyl, ethyl, propyl, i-butyl , Octyl, or hexadecyl group.

According to the process of the invention, a composition containing olefinic siloxane oligomers and containing chlorine, in particular hydrolyzable chloride, is contacted with a reducing agent, in particular an alkali metal, alkaline earth metal, aluminum or a metal hydride, to reduce the chloride content of the composition. In addition, one suffers lower yield losses. With a distillation, a separation of the siloxane oligomers would inevitably occur in light, medium and high boiler (bottoms). Due to the use according to the invention of the reducing agent, in particular if the contact times and moderate temperatures are not too long, the degree of oligomerization of the siloxane oligomers remains essentially the same and the chloride content of the composition can be significantly reduced.

By contacting it with a reducing agent, the chloride content or the content of chlorine in ppm by weight of the composition containing olefinically functionalized siloxane oligomers may preferably be at least 80% with respect to the composition containing olefinically functionalized siloxane oligomers containing chlorine be reduced. More preferably, the content of chlorine in ppm by weight of the composition containing olefinic siloxane oligomers is reduced by at least 85%, preferably by at least 90%, more preferably by at least 92%, advantageously by at least 95%, and further by the feed composition preferably at least 98%. Depending on the composition containing olefinically functionalized siloxane oligomers, also depending on the olefinic functionalization, and depending on the initial concentration of chlorine, in particular hydrolyzable chloride, the concentration of the reducing agent, the reducing power, the temperature and the contact time with the reducing agent, the content of chlorine, especially hydrolyzable chloride, in the composition preferably reduced to less than or equal to 30 mg / kg, preferably to less than or equal to 20 mg / kg, more preferably less than or equal to 5 mg / kg, particularly preferably less than or equal to 3 mg / kg to 0 mg / kg or to the detection limit.

According to the invention, a defined amount of a reducing agent, in particular an inorganic reducing agent, more preferably a metallic reducing agent or metal-containing reducing agent or an organic reducing agent having hydroxyl groups, in particular alkali metal, alkaline earth metal, metal, in particular a CAS group I to VIIIB and IIIA of the PSE , preferably the main group IIIA PSE, with boron and aluminum; or a metal hydride used in the process to lower the chlorine (id) content of the composition. Preference is given to sodium, magnesium, calcium, aluminum, lithium aluminum hydride, aluminum hydride, NaH, calcium hydride, sodium borohydride (NaBH ₄ ), ascorbic acid, dihydroxyfumaric acid, phenol, derivative of phenol, hydroxy-functionalized aromatics, and / or sodium triethoxyaluminum hydride [Na (Al (OC ₂ H ₅ ) ₃ H)]. It is preferred if the composition comprising olefinically functionalized siloxane oligomers and containing chlorine is brought into contact with the reducing agent in the presence of an alcohol.

According to the invention, preference is given to the inorganic reducing agents, in particular the metallic reducing agents, which can form sparingly soluble precipitates with the hydrogen chloride or a chloride.

More preferably, in the process according to the invention, a defined amount of reducing agent can be added to the composition containing chlorine-containing olefinically functionalized siloxane oligomers, in particular 0.2 moles of reducing agent to 2 moles of reducing agent in relation to the content of chlorine in moles with respect to the total composition Content of chlorine containing olefinically functionalized siloxanes, preferably the content of chlorine, in particular in relation to the determined content of total chloride, more preferably hydrolyzable chloride, determined after performing step vi and then the reducing agent, in particular an inorganic reducing agent, preferably a metallic reducing agent added selected from alkali metal, alkaline earth metal, metal, in particular a CAS group I to VIIIB and IIIA of the PSE, preferably the main group IIIA PSE, with boron and aluminum; and metal hydride.

It is further preferred if a defined amount of reducing agent is added to the composition and filtered or decanted after a defined reaction time. According to the invention, a defined amount of reducing agent is added from 0.2 mol to 2 mol of reducing agent in relation to the content of hydrolyzable chloride in the overall composition.

In the method according to the invention, a defined amount of reducing agent may in particular be added at least once after the implementation of step vi or in step vi or subsequently. Preferred reducing agents are metallic reducing agents, which are preferably added after step vi in a defined amount, and optionally formed solids are separated, in particular by filtration and / or decantation, solids are preferably precipitates, such as NaCl, aluminum chloride, optionally volatile components are separated, such as solvents, in particular alcohol, preferably under reduced pressure and elevated temperature. For example, after the removal of the hydrolysis alcohol, a defined amount of reducing agent is preferably added. Reducing agents particularly suitable for the process should, in a reaction with the catalyst, for example HCl, or with organically bonded chlorine, such as Cl-Si; do not form any water.

According to the invention, it is preferred that after the performance of step vi, ie after separation of the hydrolysis alcohol and the optionally present solvent, the content of chlorine is determined and then a reducing agent is added. As a defined amount in moles of reducing agent are added in relation to the specific amount of moles of chlorine, in particular the specific amount of hydrolyzable chloride in moles, from 0.4 to 1.4 moles of base. Preferably, a ratio of moles of chlorine atoms to moles of reducing agent is from 1: 0.1 to 1: 2, preferably from 1: 0.4 to 1: 0.8, preferably from 1: 0.5 to 1: 0.7 , discontinued. The reducing agent may preferably react at a temperature of 0 to 80 ° C for a defined time, and formed solids may subsequently be separated. Preferably, in terms of the determined content of hydrolyzable chloride in moles, a substoichiometric amount of a reducing agent in moles is added. It is particularly preferred for 1 to 180 minutes at a temperature of 0 to 60 ° C, preferably from 0 to 50 ° C, more preferably less than or equal to 45 ° C to room temperature, reacted, preferably with thorough mixing, preferably stirred.

The reaction in step (v) preferably takes place in the presence of a defined amount of water of greater than 0.60 to 1.48 moles of water per mole of silicon atoms of the alkoxysilanes of the formula II and / or III used and optionally of the formula IV. The water is preferably demineralized. In particular, 0.70 to 1.45 mol of water are used, preferably greater than 0.75 to 1.43 mol of water, more preferably greater than or equal to 1.2 to 1.43 mol of water, preferably of from 1.25 to 1.4 mol, in particular also 1.3 to 1.35 moles of water per mole of silicon atoms of the alkoxysilanes of the formula II and / or III used, in particular each having x = 0 and y = 0, and optionally of the formula IV. Also, all in the disclosed Area included numerical values of moles of water as disclosed, in particular up to the second decimal place, such as 0.61, 0.62; 0.63; 0.64; 0.65; 0.66; 0.67; 0.68; 0.69; 0.70 to 1.05 as well as the intervening numerical values 1.06; 1.07; 1.08, 1.09, 1.11; 1.12; 1.13; 1.14; 1.15; 1.16; 1.17; 1,18, 1,19; 1; 21; 1.22; 1.23; 1.24; 1.26, 1.27, 1.28; 1.29; 1.30; 1.31; 1.32; 1.33; 1.34; 1.35; 1.36; 1.37; 1.38; 1.39; 1.40; 1.41; 1.42; 1.43, 1.44; 1.45; 1.46; 1.47. It is clear to the person skilled in the art that the water can be added to the process both initially, in portions, continuously or together with one or all of the silanes. Preferably, the water is dosed continuously or with at least one interruption over a period of less than 1 minute to 100 minutes and the reaction of the alkoxysilanes preferably at reaction temperatures in the range preferably 40 ° C to 80 ° C, more preferably in the range of 50 to 80 ° C. , in particular at a pH less than 7 performed.

In the process according to the invention, at least once in step v and / or during step vi or subsequently a defined amount of alcohol can be added, preferably the corresponding alcohol of the alkoxysilane is used. Depending on the method, it is also possible to add 1 to 6, in particular 2 to 6, times a defined amount of alcohol; in particular 0.001 to 5.0 volume units of alcohol are added per volume unit of alkoxysilane, preferably 0.01 to 3, particularly preferably 0.25 added to 1 and separated again, in particular, the alcohol is removed by distillation. For this purpose, distilled under reduced pressure and elevated temperature, in particular at a pressure of less than 300 mbar, preferably less than 180 mbar, more preferably less than 120 mbar, wherein the pressure is preferably adjusted so that the temperature load of the bottom product at around 90 ° C or lower temperature lies. The solvent used and / or the alcohol used are anhydrous, in particular the solvent or the alcohol used with a water content of less than 1 ppm by weight. For solvents containing water, this water content must be taken into account during the reaction.

The alcohol already present and / or produced during the reaction is essentially, preferably completely, removed from the reaction mixture in all process variants according to the invention. The distillative removal of the alcohol is preferably carried out under reduced pressure. The distillative removal of the alcohol is preferably carried out until a temperature is reached in the top of the column, the boiling point of water or preferably until a vacuum of 100 mbar, in particular less than or equal to 100 mbar equal to 0.01 mbar, permanently set can be. As a rule, the resulting composition according to the invention is then essentially solvent-free, in particular alcohol-free. The composition thus obtained preferably corresponds directly to the composition according to the invention, and preferably does not itself have to be further purified.

Preferred alcohols correspond to the hydrolysis alcohol which is formed by the at least partial hydrolysis and / or condensation. These include ethanol or methanol. It will be understood by those skilled in the art that the reaction may also be in the presence of another conventional solvent, with those which are easily and preferably completely distilled off being preferred, but may not be, for example, ethers, ketones, hydrocarbons or esters. However, suitable solvents may also be ethyl acetate, THF, ketones, ethers or hydrocarbons. It is clear to the person skilled in the art that, for economic and economic reasons, the solvent used is an alcohol which also forms as a hydrolysis alcohol. Mixtures of alcohols can therefore also be used in principle. In all process variants, the solvent and the alcohol formed during the reaction are preferably removed by distillation from the reaction mixture.

Likewise, in the process according to the invention, a composition containing olefinically functionalized siloxane oligomers containing chlorine can additionally be brought into contact with a base, such as an amine, alkoxide and / or alkali metal alkylate, preferably selected from ammonia, LDA (Li-diisopropylamide), Li Isopropylhexylamide, potassium hexamethylsilazane, hexamethyldisilazane, alkali metal alcoholate, in particular sodium or potassium methoxide, sodium or potassium ethoxide, alkali metal alkylate, in particular an alkali metal alkylate having an alkyl group having 1 to 4 carbon atoms, preferably butyl Li. Preferably, the bases form sparingly soluble compounds with chlorine and can then be filtered off or separated by decantation.

Furthermore, the subject matter of the process according to the invention is that a composition which has been brought into contact with a reducing agent can subsequently be further reduced in the chloride content by treatment with an ion exchanger. The product thus obtained preferably contains less than 40 ppm by weight, preferably less than 5 ppm by weight of hydrolyzable chloride, more preferably less than 3 ppm by weight.

In the process according to the invention, the anion exchanger preferably has a carrier polymer with quaternary alkylammonium groups and / or with tertiary dialkylamino groups, the quaternary alkylammonium groups in particular having hydroxide ions as counterions and / or the tertiary dialkylamino groups in the form of free base present. It is particularly preferred if the basic anion exchanger is a styrene-divinylbenzene copolymer having trialkylammonium groups, in particular in the OH form, and / or a styrene-divinylbenzene copolymer having dialkylamino groups in the form of the free base. When using basic anion exchangers with a styrene-divinylbenzene copolymer having trialkylammonium groups in the chloride form, the chlorides are converted to the OH form before use, for example with an alkali hydroxide solution. The alkali metal hydroxide solutions used are preferably aqueous solutions of potassium hydroxide, sodium hydroxide or other bases soluble in water or water-alcohol, such as ammonia, or alkali metal carbonates, such as Na ₂ CO ₃ . In this case, after the conversion of the anion exchanger into the OH form, before being brought into contact with the composition comprising olefinic siloxane oligomers, the anion exchanger is rinsed with an alcohol in order to displace in particular excess water. The alcohol used is preferably the alcohol which would be formed by hydrolysis of the respective alkoxy groups. For methoxy groups, methanol or ethanol for ethoxy groups in the alkoxysilane.

Quaternary ammonium groups are both alkylammonium and N-alkylimine functional groups such as N-alkyl-pyridinium groups. Suitable alkyl groups contain 1 to 20 carbon atoms, preferably having 1 to 4 carbon atoms, and are preferably methyl or ethyl groups. According to the invention, weakly basic anion exchangers are loaded with hydroxide ions and, in particular, they have nitrogen-containing groups.

It is also preferred that the compositions containing olefinically functionalized siloxane oligomers be contacted with the anion exchanger in an ion exchange column at a flow rate of 0.01 m / h to 15 m / h and substantially chlorine free compositions containing olefinically functionalized siloxane oligomers are obtained the ion exchange column in particular has an inner diameter of 3 cm and preferably has a height of 15 cm. It will be understood by those skilled in the art that the dimension of the ion exchange column can be varied depending on the flow rate, the viscosity of the composition, the particle size of the ion exchanger supports, and the desired amount of product flow.

The invention also provides the use of a reducing agent for the substitution of Si-Cl for Si-O-, such as Si-OH or Si-OR with R equal organic radical, in compositions containing olefinically functionalized siloxane oligomers and having a content of chlorine and / or for the separation of hydrolysis and / or condensation catalysts in the form of acids and / or for the separation of hydrogen chloride from compositions containing olefinically functionalized siloxane oligomers.

According to the invention, compositions containing olefinically functionalized siloxane oligomers with a chlorine or chlorine content content if they have more than 70 mg / kg of chlorine, preferably with a content of greater than or equal to 80 mg / kg of total chloride or greater than 75 mg / kg of hydrolyzable chloride.

According to the invention, compositions comprising olefinically functionalized siloxane oligomers with a chlorine or chlorine content content which preferably have a molecular weight in the range from 200 to 3,000 g / mol are considered. The molecular weight can be measured by the GPC method known to those skilled in the art. The molecular weight (determination by GPC) is preferably in the range from 200 to 3,000, particularly preferably the average molecular weight is from 500 to 1,300, furthermore preferably from 500 to 1,000, and also preferably from 600 to 800 g / mol. It is clear to the person skilled in the art that if the molar masses are too high, the viscosity can be too high and a satisfactory flow rate can be set only when diluted with a solvent.

It has surprisingly been found that the compositions of olefinically functionalized siloxane oligomers obtained by the process according to the invention due to the further reduction of the content of chlorine are significantly more stable to hydrolysis, although they are no longer distilled consuming than before. As a result, the compositions of the siloxane oligomers prepared according to the invention prove to be significantly more stable than known oligomers.

According to one alternative, the olefinically functionalized siloxane oligomers in the composition, in particular of the formula I, preferably have a ratio of silicon atoms with A and B radicals with the proviso that a greater than 1, b greater than or equal to 0 and c greater than or equal Is 0, and (a + b + c) is greater than or equal to 2, from Si to (A + B residues) from 1 to 1 to about 1.22 to 1, preferably from 1: 1 to 1.15: 1.

In addition or as an alternative to one or more of the aforementioned features, the composition preferably has a molar ratio of A residues to B residues of from 1: 0 to 1: 8, preferably from about 1: 0 to 1: 4, more preferably a ratio of 1: 0 to 1: 2, preferably 1: 0 to 1: 1, more preferably 1: 1.

A particular advantage of the compositions according to the invention containing olefinically-functionalized siloxane oligomers is that the reduced content of chlorine directly improves the stability as well as the processability of the siloxane oligomers with polymers, for example in kneading or compounding. Specifically, the corrosion of ferrous machinery decreases, since the chloride content could be further reduced.

It may be preferred that the composition and / or the siloxane oligomer also contain trialkylsilane groups, such as trimethylsilane or triethylsilane groups, for example by the addition of alkoxytrialkylsilane to adjust the degree of oligomerization.

According to the process of the invention, it is possible to provide essentially chlorine-free compositions of mixtures of olefinic siloxane oligomers in which in particular more than 20% by weight of the siloxane oligomers have a degree of oligomerization of greater than 8, the number of silicon atoms (n) per oligomer is greater than 8 ( n> 8), wherein at the same time the viscosity is preferably less than or equal to <3,000 mPas, in particular less than 1,000 mPas and preferably greater than 5 mPas, especially preferably less than or equal to 500 mPas, and in particular greater than or equal to 10 mPas. Alternatively, it is preferred if the viscosity of the substantially chlorine-free composition containing olefinically functionalized siloxanes is less than or equal to 3,000 mPas and greater than 7 mPas, preferably less than 2,500, in particular less than 500 mPas and greater than 10 mPas, alternatively preferably less than or equal to 1,000 mPas, in particular less equal to 500 mPas and greater than 12 mPas. Such compositions are excellent for compounding with elastomers or thermoplastics and have the better properties mentioned above.

A particular advantage of the composition according to the invention is that it has a very low chlorine content due to its manufacture and thus leads to a considerable improvement in the fire protection properties when processed in cable compositions.

In general, the siloxane oligomers may be linear and / or cyclic oligomers having M, D structures and T structure. Only when tetraalkoxysilane is added during the preparation or before the oligomers are processed are siloxane oligomers with M, D, Q and optionally T structures formed. According to the invention used composition containing chloride, and the prepared, substantially chlorine-free compositions have siloxane oligomers, in particular of formula I, in which the sum of (a + b) is an integer greater than or equal to 2, in particular from 4 to 30, and from 6 to 30, preferably from 8 to 25, and c is optionally greater than or equal to 1, such as 1 to 20, especially 2 to 15. If the degrees of oligomerization are too high, the composition should preferably form with the corresponding alcohol formed by hydrolysis of the alkoxy groups would be diluted. These are preferably methanol or ethanol.

Compositions used in the process according to the invention may have at least 20% by weight of siloxane oligomers, in particular of the formula I, in which the degree of oligomerization of olefinically functionalized siloxane oligomers is greater than 4, in particular greater than 6, particularly preferably greater than 8. It is further preferred if at least 20% by weight of the siloxane oligomers, in particular of the formula I, a and / or b, are each independently an integer greater than 4, in particular greater than 6, preferably greater than 8, with a greater than or equal to 1 and b equal to 0 or greater is 1, preferably each a and b are independently greater than 4, in particular independently greater than 6, and optionally with c in (a + b + c) greater than or equal to 1.

According to an alternative, essentially chlorine-free compositions of purely olefinically substituted siloxane oligomers are prepared, in particular of the formula I where a is an integer greater than or equal to 2, preferably greater than or equal to 8. Preferred olefinic groups are linear, branched or cyclic, alkenyl, cycloalkenyl alkylene-functional groups each having 2 to 16 carbon atoms, preferably a vinyl, allyl, butenyl, such as 3-butenyl, pentenyl, hexenyl, ethylhexenyl, heptenyl, octenyl, cyclohexenyl C1 to C8 alkylene, preferably cyclohexenyl-2-ethylene, such as 3'-cyclohexenyl-2-ethylene and / or cyclohexadienyl-C1 to C8-alkylene, preferably cyclohexadienyl-2-ethylene group. Particularly preferred is vinyl. Optionally, the composition may be based on a siloxane oligomer prepared in the presence of tetraalkoxysilane.

According to a second preferred alternative, substantially chlorine-free compositions of olefinic- and alkyl-substituted siloxane oligomers are prepared, in particular of the formula I with a greater than or equal to 1 and b greater than or equal to 1. In these compositions, it is further preferred if the molar ratio of A radicals to B residues is 1: 0 to 1: 8, in particular the ratio of a: b is 1: 0 to 1: 8, in particular 1: 0 or 1: 1 to 1: 8. Optionally, the composition may be based on a siloxane oligomer prepared in the presence of tetraalkoxysilane. Preferred alkyl radicals have 1 to 6 C atoms.

According to a further preferred alternative, substantially chlorine-free compositions of vinyl- and alkyl-substituted siloxane oligomers are prepared with a molar ratio of A radicals to B radicals 1: 0 to 1: 8, in particular of a: b equal to 1: 0 to 1: 8, in particular 1: 0 or 1: 1 to 1: 8. Optionally, the compositions may be based on a siloxane oligomer prepared in the presence of tetraalkoxysilane. Preferred alkyl radicals have 1 to 6 C atoms.

A structural element - a monomeric siloxane unit - is understood to mean the individual structural unit M, D, T or Q, ie the structural unit derived from an alkoxy-substituted silane, which is characterized by at least partial hydrolysis to optionally complete hydrolysis and at least partial condensation in a condensate forms. According to the invention, in particular the siloxane oligomers may form with the following structural elements, such as preferably:
(R ¹ O) [(R ¹ O) _1-x (R ²⁾ _x Si (A) O] _a R ^1; (R ¹ O) [(R ¹ O) _1-x (R ²⁾ _x Si (A) O] _a; [(R ¹ O) _1-x (R ²⁾ _x Si (A) O] _a; [(R ¹ O) _1-x (R ²⁾ _x Si (A) O] _a R ^1; (R ³ O) [Si (Y) ₂ O] _c ; [Si (Y) ₂ O] _c R ³ , (R ³ O) [Si (Y) ₂ O] _c R ³ ; [Si (Y) ₂ O] _c ; (R ³ O) [Si (B) (R ⁴ ) _y (OR ³ ) _1-y O] _b R ³ ; [Si (B) (R ⁴ ) _y (OR ³ ) _1-y O] _b R ³ , [Si (B) (R ⁴ ) _y (OR ³ ) _1-y O] _b ; (R ³ O) [Si (B) (R ⁴ ) _y (OR ³ ) _1-y O] _b R ^{3 can form} the chain-like, cyclic and / or crosslinked structures and in the presence of tetraalkoxysilanes or their hydrolysis and / or condensation products Spatially networked structures can also be formed. The structural elements with free valencies on the Si atom are covalently saturated via -O-Si and the free valencies on the O atom with -Si bridged bonds of other structural elements, alkyl or possibly hydrogen. The structural elements can assume a random or even statistical arrangement in the condensates, which, as one skilled in the art knows, can also be controlled by the order of addition and the hydrolysis and / or condensation conditions. The general formula I does not reflect the actual structure or composition. It corresponds to an idealized representation.

The content of M, D, T or Q structures is generally determined by a method known per se to the person skilled in the art, preferably by means of ²⁹ Si NMR.

The definition for M, D, T and Q structures usually refers to the number of bound oxygens:

One could also speak of T0, T1, T2 and T3, which in practice, however, is rather uncommon: R-Si (OEt) 3 T0 R-Si (OEt) 2 (OSi) T1 R-Si (OEt) (OSi) 2 T2 R-Si (OSi) 3 T3

Thus, in order to be able to describe silicones and siloxanes or silanoligomers more clearly, it is also possible to resort to the so-called M, D, T and Q structures instead of an idealized formulaic description. For a more detailed nomenclature of the naming of such siloxane structures, reference should be made to the "Römpp Chemielexikon" - keyword: silicones. For example, from units M only dimers can be formed with M ₂ . For building chains, compositions of units D and M are required, so that trimers (M ₂ D), tetramers (M ₂ D ₂ ) and so on can be built up to linear oligomers with M ₂ D _n . For the formation of cyclic oligomers units D are needed. In this way, for example, rings with D ₃ , D ₄ , D ₅ or higher can be constructed. Branched or crosslinked structural elements, which also include spiro compounds, are obtained if structural units T and / or Q are present together. Conceivable crosslinked structures can be described as T _n (n ≥ 4); D _n T _m (m <n); D _n T _m (n >>m); D ₃ T ₂ ; M ₄ Q; D ₄ Q and so on, to name only a few possible options. Building units M are also referred to as stoppers or regulators, while D units are referred to as chain or ring formers and the T and optionally also the Q units as network formers. Thus, the use of tetraalkoxysilanes due to the four hydrolyzable groups and access of water or moisture units Q and thus the formation of a network (space-crosslinked) effect. In contrast, fully hydrolyzed trialkoxysilanes can cause branching, T units [-Si (-O-) _3/2 ], in one structural element, for example MD ₃ TM ₂ for an oligomer with a degree of oligomerization of n = 7, in which structural representations the respective Functionalities are to be defined at the free valences of the silyloxy units.

• – „Strukturuntersuchungen von oligomeren und polymeren Siloxanen durch hochauflösende 29Si-Kernresonanz“, H.-G. Horn, H. Ch. Marsmann, Die Markromolekulare Chemie 162 (1972), 255–267 ;
• – „Über die 1H-, 13C- und 29Si-NMR chemischen Verschiebungen einiger linearer, verzweigter und cyclischer Methyl-Siloxan-Verbindungen“, G. Engelhardt, H. Jancke; J. Organometal. Chem. 28 (1971), 293–300 ;
• – „Chapter 8 – NMR spectroscopy of organosilicon compounds“, Elizabeth A. Williams, The Chemistry of Organic Silicon Compounds, 1989 John Wiley & Sons Ltd, 511–533 .

Further details on the understanding of nomenclature of M-, D-, T- and Q-structures as well as related investigation methods are:

• - "Structural investigations of oligomeric and polymeric siloxanes by high-resolution 29Si nuclear resonance", H.-G. Horn, H.C. Marsmann, The Markromolecular Chemistry 162 (1972), 255-267 ;
• - "About the 1H, 13C, and 29Si NMR chemical shifts of some linear, branched, and cyclic methyl siloxane compounds", G. Engelhardt, H. Jancke; J. Organometal. Chem. 28 (1971), 293-300 ;
• - "Chapter 8 - NMR spectroscopy of organosilicone compounds", Elizabeth A. Williams, The Chemistry of Organic Silicon Compounds, 1989 John Wiley & Sons Ltd, 511-533 ,

A composition preferably contains siloxane oligomers which are obtained by random and / or random homo- or co-hydrolysis and / or homo- or co-condensation and / or block condensation of said structural elements, based on the alkoxysilanes of the formulas substituted according to the invention with A or B radicals II, III and / or IV, arise and / or form under the selected experimental conditions. The substitution pattern of the structural elements applies correspondingly also to the non-idealized chain-form, cyclic, crosslinked and / or spatially crosslinked siloxane oligomers in the composition, wherein the silyl groups of the siloxane oligomers may independently be substituted as follows: Y is an OR ³ or crosslinked and / or spatially crosslinked structures independently of one another OR ³ or O _1/2 - in a siloxane bond, with radicals A and / or B as defined, R ³ in the siloxane oligomers essentially corresponds to an alkyl radical as defined for R ³ , wherein in cross-linked and / or space-crosslinked structures, it is also possible independently of each other to form siloxane bonds with O _1/2 from the radicals OR ³ , or these radicals can be present independently of one another as O _1/2 and optionally independently with R ² and / or R ⁴ and which as defined correspond to an alkyl radical having 1 to 15 carbon atoms, with -OR ¹ , R ¹ can also be defined as an alkyl Radical with 1 to 4 carbon atoms.

After carrying out the process according to the invention, the substantially chlorine-free composition comprising olefinically functionalized siloxane oligomers, in particular at least one siloxane oligomer according to the idealized formula I, which are added as further components: at least one organic solvent, an organic polymer, water, salt, filler, additive, Pigment or a mixture of at least two of said components.

Essentially chlorine-free compositions of olefinically functionalized siloxane oligomers prepared according to the invention have a content of alcohol with respect to the total composition, preferably of free alcohol, of less than or equal to 2% by weight to 0.0001% by weight, in particular less than or equal to 1.8 Wt .-%, preferably less than or equal to 1.5 wt .-%, more preferably less than or equal 1.0 wt .-%, particularly preferably from 0.5 wt .-% to 0.001 wt .-%, in particular up to the detection limit. In this case, a composition has this low content of alcohol, preferably free alcohol, over at least 3 months, preferably over a period of 6 months. These low levels of VOC can be ensured by the process according to the invention, which provides especially chlorine-poor siloxanes with a low alkoxy content.

Compounds of the formula II which can be used according to the invention are vinyltriethoxysilane, vinyltrimethoxysilane, allyltriethoxysilane, allyltrimethoxysilane, butenyltriethoxysilane, butenyltrimethoxysilane, cyclohexenylalkylenetrimethoxysilane, in particular cyclohexenyl-2-ethylenetrimethoxysilane, cyclohexenyl-2-ethylenetriethoxysilane, more preferably 3'-cyclohexenyl- 2-ethylene-triethoxysilane and / or 3'-cyclohexenyl-2-ethylene-trimethoxysilane; Cyclohexenedienyl-alklyltriethoxysilane, hexenyltriethoxysilane, hexenyltrimethoxysilane, ethylhexenyltrimethoxysilane, ethylhexenyltriethoxysilane, octenyltriethoxysilane, octenyltrimethoxysilane, with the methoxy-substituted ones being particularly preferred.

Preferred alkylalkoxysilane compounds of the formula III are:
Compounds of the formula III where y = 0 or 1, where B is a linear or branched alkyl radical having 1 to 18 C atoms, in particular having 1 to 8 C atoms, preferably a methyl, ethyl, particularly preferably n-propyl -, iso-propyl, butyl, pentyl, hexyl, heptyl, octyl, hexadecyl or octadecyl radical, R ^{4 is} a linear, branched or cyclic alkyl radical having 1 to 15 carbon atoms, in particular with 1 to 8 C atoms, preferably a methyl, ethyl, particularly preferably n-propyl, iso-propyl and / or octyl radical, R ^{3 is} a linear and / or branched alkyl radical having 1 to 3 C atoms , particularly preferably a methyl, ethyl and / or iso-propyl or n-propyl radical. B is particularly preferably a methyl, ethyl, propyl, octyl, hexadecyl or octadecyl radical and R ^{4 is} a methyl or ethyl radical and R ^{1 is} a methyl or ethyl radical, the methoxy-substituted radicals being especially are preferred.

Preferred exemplified compounds of the formula III are: methyltrimethoxysilane, methyltriethoxysilane (MTES), propyltrimethoxysilane (PTMO), dimethyldimethoxysilane (DMDMO), dimethyldiethoxysilane, propylmethyldimethoxysilane, propylmethyldiethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-octylmethyldimethoxysilane, n- Hexylmethyldimethoxysilane, n-hexylmethyldiethoxysilane, propylmethyldiethoxysilane, propylmethyldiethoxysilane, propytriethoxysilane, butyltrimethoxysilane, i-butyltrimethoxysilane, i-butyltriethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, i-octyltrimethoxysilane, i-octyltriethoxysilane, n-hexyl triethoxysilane, cyclohexyltriethoxysilane, n-propyl-tri-n-butoxysilane, n-propyl trimethoxysilane, n-propyl triethoxy silane, hexadecyltriethoxysilane, hexadecyltrimethoxysilane, octadecyltriethoxysilane, octadecyltrimethoxysilane, Octadecylmethyldiethoxysilan, octadecylmethyldimethoxysilane, Hexadecylmethyldimethox ysilane and / or hexadecylmethyldiethoxysilane and mixtures of these silanes or a mixture comprising at least two of the silanes.

Particularly preferred combinations of compounds of the formulas II, III and / or IV for the preparation of the olefinically functionalized siloxane oligomers or the olefinically functionalized siloxane oligomers obtainable therefrom are:
Vinyltriethoxysilane and tetraethoxysilane; Vinyltrimethoxysilane and tetramethoxysilane; Vinyltriethoxysilane and methyltriethoxysilane; Vinyltriethoxysilane, methyltriethoxysilane and tetraethoxysilane; Vinyltrimethoxysilane and methyltrimethoxysilane; Vinyltrimethoxysilane, methyltrimethoxysilane and tetraethoxysilane or tetramethoxysilane; Vinyltriethoxysilane and ethyltriethoxysilane; Vinyltriethoxysilane, ethyltriethoxysilane and tetraethoxysilane; Vinyltrimethoxysilane and ethyltrimethoxysilane; Vinyltrimethoxysilane, ethyltrimethoxysilane and tetraethoxysilane or tetramethoxysilane; Vinyltriethoxysilane and propyltriethoxysilane; Vinyltriethoxysilane, propyltriethoxysilane and tetraethoxysilane; Vinyltrimethoxysilane and propyltrimethoxysilane; Vinyltrimethoxysilane, propyltrimethoxysilane and tetraethoxysilane or tetramethoxysilane; Vinyltriethoxysilane and iso-butyltriethoxysilane; Vinyltriethoxysilane, isobutyltriethoxysilane and tetraethoxysilane; Vinyltrimethoxysilane and iso-butyltrimethoxysilane; Vinyltrimethoxysilane, isobutyltrimethoxysilane and tetramethoxysilane; Vinyltriethoxysilane and octyltriethoxysilane; Vinyltriethoxysilane, octyltriethoxysilane and tetraethoxysilane; in particular with vinyltriethoxysilane and tetraethoxysilane in the ratio of 1: 0.20 to 1: 0; Vinyltrimethoxysilane and octyltrimethoxysilane; Vinyltrimethoxysilane, octyltrimethoxysilane and tetramethoxysilane; in particular with vinyltrimethoxysilane and tetramethoxysilane in a ratio of 1: 0.20 to 1: 0.

In addition or as an alternative to one of the abovementioned features, the process may also employ as processing aid at least one silicone oil, such as polydimethylsiloxane, paraffin, paraffin oil or a mixture containing one of these processing aids. A particularly preferred processing aid is polydimethylsiloxane, preferably having a viscosity of about 150 to 400 mm ² / s, particularly preferred alternatives have a kinematic viscosity of about 200 mm ² / s or 350 mm ² / s.

It will be understood by those skilled in the art that the substantially chloride-free compositions containing olefinically functionalized siloxane oligomers treated by the process of the present invention are diluted with a diluent, as desired, or with a polymer such as a thermoplastic base polymer such as PE, PP, or an elastomer such as EVA. can be added or compounded. Other thermoplastic base polymers and elastomers are mentioned below by way of example, the person skilled in the art knows that generally all thermoplastic base polymers or polymers or elastomers are suitable.

The person skilled in the usual diluents for alkoxysiloxanes are known, for example, alcohols, ethers, ketones, hydrocarbons, or mixtures thereof are mentioned here. The compositions of the olefinically functionalized siloxane oligomers can thus be prepared depending on the desired application as a concentrate or else as a dilute composition of from 99.9 to 0.001% by weight and all intermediate values of functional siloxane oligomers in the overall composition. Preferred dilutions contain from 10 to 90% by weight of functional siloxane oligomers, more preferably from 20 to 80% by weight, more preferably from 30 to 70% by weight.

In particular, acrylonitrile-butadiene-styrene (ABS), polyamides (PA), polymethyl methacrylate (PMMA), polycarbonate (PC), polyethylene (PE), such as LDPE, LLD-PE, m-PE, polypropylene are used as thermoplastic base polymers in the context of the invention (PP), polystyrene (PS), polyvinyl chloride (PVC), chloroprene, as well as the ethylene-based polymers ethylene-vinyl acetate copolymers (EVA), EPDM or EPM and / or celluloid or silane-co-polymerized polymers understood and, for example unsaturated functional monomers including silanes such as VTMO, VTEO, and monomers such as ethylene and other olefins prepared base polymers, monomers and / or prepolymers precursors of these base polymers such as ethylene, propylene. Further preferred elastomers can be selected from the series ethylene-propylene Rubber (EPR), ethylene-propylene-diene rubber (EPDM), styrene-butadiene rubber (SBR), natural rubber (NR), acrylate copolymer rubber (ACM), acrylonitrile-butadiene rubber (NBR) and / or polybutadiene rubber ( BR).

The invention also provides the use of the substantially chloride-free composition according to the invention as an adhesive, as a crosslinking agent by graft polymerization and / or hydrolytic condensation in a conventional manner, for the preparation of olefinically functionalized siloxane oligomers grafted polymers, prepolymers and / or mineral filled polymers (compounds), in particular in the production of thermoplastics or elastomers, preferably of mineral-filled thermoplastics, elastomers or prepolymers thereof, for grafting or in the polymerization of thermoplastic polyolefins, as drying agents, in particular as water scavengers for silicone sealants, in crosslinkable polymers for the production of cables, for the preparation of crosslinkable polymers, as an oil phase in an emulsion and / or together with organosilanes or organopolysiloxanes, for filler modification (filler coating), resin modification (Ad as a component in coating systems (in particular sol-gel systems or hybrid systems), for modifying cathodes and anode materials in batteries, as an electrolyte fluid, as an additive in electrolyte fluids, for the modification of fibers, in particular glass fibers and Natural fibers, as well as for the modification of textiles, for modifying fillers for the artificial stone industry, as building protection or component in building preservatives, as an additive for mineral hardening materials, for the modification of wood, wood fibers and cellulose.

For the joint use of the composition with organosilanes or organosiloxanes according to the invention is fully based on the disclosure of EP 1 205 481 B1 In particular, the disclosure of paragraph [0039] and the list of organosilanes and organosiloxanes disclosed therein.

Thus, an olefinically functionalized siloxane oligomer composition prepared in an alternative, flexible and simultaneously economical manner can be used to advantage.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0518057 B1 [0005, 0006]
• CN 100343311 C [0007]
• JP 10-298289A [0008]
• JP 2004-099872 [0009]
• EP 1205481 B1 [0076]

Cited non-patent literature

• "Structural investigations of oligomeric and polymeric siloxanes by high-resolution 29Si nuclear resonance", H.-G. Horn, H.C. Marsmann, The Markromolecular Chemistry 162 (1972), 255-267 [0063]
• "About the 1H, 13C, and 29Si NMR chemical shifts of some linear, branched, and cyclic methyl siloxane compounds", G. Engelhardt, H. Jancke; J. Organometal. Chem. 28 (1971), 293-300 [0063]
• "Chapter 8 - NMR spectroscopy of organosilicone compounds", Elizabeth A. Williams, The Chemistry of Organic Silicon Compounds, 1989 John Wiley & Sons Ltd, 511-533 [0063]

Claims (16)

A process for preparing a composition containing olefinically functionalized siloxane oligomers, which composition is substantially chlorine free, by contacting a composition containing olefinically functionalized siloxane oligomers and containing chlorine with a reducing agent. A method according to claim 1, characterized in that the reducing agent is an organic or inorganic reducing agent or a reducing agent comprising organic and inorganic compounds. Process according to Claim 1 or 2, characterized in that the olefinically functionalized siloxane oligomers have at most one olefinic radical on the silicon atom (per Si). Method according to one of claims 1 to 3, characterized in that the olefinically functionalized siloxane oligomers have at most one olefinic radical on the silicon atom, and in that - the olefinically functionalized siloxane oligomers Si-O-crosslinked structural elements, the chain-like, cyclic, crosslinked and / or form space-crosslinked structures, wherein at least one structure in idealized form corresponds to the general formula I, (R ¹ O) [(R ¹ O) _1-x (R ²⁾ _x Si (A) O] _a [Si (Y) ₂ O] _c [Si (B) (R ⁴⁾ _y (OR ³⁾ _{1 -y} O] _b R ³ (I) - wherein the structural elements are derived from alkoxysilanes and - A in the structural element corresponds to an olefinic radical and - B in the structural element corresponds to a saturated hydrocarbon radical, - Y corresponds to OR ³ or in crosslinked and / or spatially crosslinked structures independently of one another OR ³ or O _1/2, - wherein R ¹ is independently a linear, branched and / or cyclic alkyl radical having 1 to 4 carbon atoms, and optionally H, - R ³ are each independently a linear, branched and / or cyclic alkyl Radical having 1 to 4 C atoms, and optionally H, and R ² and / or R ⁴ each independently correspond to a linear, branched or cyclic alkyl radical having 1 to 15 C atoms, - a, b, c, x and y are independently integers corresponding to 1 ≤ a, 0 ≤ b, 0 ≤ c, x is independently 0 or 1, y is independently 0 or 1, and (a + b + c) ≥ 2, specifically, x is 0 and / or y gl oak 0. A method according to claim 4, characterized in that c is 0 or greater than 1. Method according to one of claims 1 to 4, characterized in that the olefinically functionalized siloxane oligomers and / or the formula I are derived from (i) at least one olefinically-functionalized alkoxysilane of the general formula II, A-Si (R ² ) _x (OR ¹ ) _3-x (II), wherein in formula II A is an olefinic radical, R ^{2 is} independently a linear, branched or cyclic alkyl radical having 1 to 15 C atoms and x is 0 or 1 and R ^{1 is} independently a linear, branched and / or cyclic alkyl radical 1 to 4 carbon atoms correspond, (ii) in the presence of a hydrolysis and / or condensation catalyst optionally (iii) with an alkoxysilane of the formula III B-Si (R ⁴ ) _y (OR ³ ) _3-y (III), wherein in formula III B a saturated hydrocarbon radical, R ^{3 are} each independently a linear, branched and / or cyclic alkyl radical having 1 to 4 C-atoms and R ^{4 is} a linear, branched or cyclic alkyl radical having 1 to 15 C atoms correspond and y is 0 or 1, and / or optionally (iv) with a tetraalkoxysilane of formula IV Si (OR ³ ) ₄ (IV), wherein in formula IV R ^{3 are} each independently a linear, branched and / or cyclic alkyl radical having 1 to 4 carbon atoms, (v) with a defined amount of water, in particular from 0.5 to 1.5 moles of water each Mol of silicon atoms of the formulas II, III and / or IV, if appropriate in the presence of a solvent, preferably alcohol, are reacted to form the siloxane oligomers and, if appropriate, (vi) the hydrolysis alcohol and the optionally present solvent are essentially removed, and in particular that in the olefinically-functionalized alkoxysilane of the general formula II, A-Si (R ² ) _x (OR ¹ ) _3-x (II), A is a linear, branched or cyclic alkenyl or cycloalkenylalkylene functional group having in each case 2 to 16 C atoms, preferably a vinyl, allyl, butenyl, pentenyl, hexenyl, ethylhexenyl, heptenyl, octenyl, Cyclohexenyl-C1 to C8-alkylene, preferably cyclohexenyl-2-ethylene, such as 3'-cyclohexenyl-2-ethylene; and / or cyclohexadienyl-C1 to C8-alkylene, particularly preferably a cyclohexadienyl-2-ethylene group, in particular x is 0, and R ^{1 is} independently a linear, branched and / or cyclic alkyl radical having 1 to 4 C- Atoms, and / or independently - in the alkoxysilane of the formula III, B-Si (R ⁴ ) _y (OR ³ ) _3-y (III), the unsubstituted hydrocarbon radical B is a linear, branched or cyclic alkyl radical having 1 to 16 C atoms. A method according to claim 6, characterized in that the alkoxysilanes of the formulas II, III and / or IV are at least partially hydrolyzed and condensed in the presence of an acidic catalyst, in particular with hydrogen chloride, and preferably the alcohol is substantially completely removed. Method according to one of claims 1 to 7, that a defined amount of reducing agent is added to the composition containing olefinically functionalized siloxane oligomers and containing chlorine, in particular 0.2 moles reducing agent to 2 moles reducing agent in relation to the content chlorine in moles relative to the total composition containing olefinically functionalized siloxanes containing chlorine, preferably the content of chlorine is determined after carrying out step vi and then the reducing agent is added. Method according to one of claims 1 to 8, characterized in that a defined amount of reducing agent is added and filtered or decanted after a defined reaction time. A method according to claim 9, characterized in that a composition of olefinically functionalized siloxane oligomers is obtained, which is substantially free of chlorine, wherein the content of chlorine in the total composition is less than or equal to 70 mg / kg to 0 mg / kg. Method according to one of claims 1 to 10, characterized in that the reducing agent is selected from metallic or metal-containing reducing agents or organic reducing agents having hydroxy groups, in particular alkali metal, alkaline earth metal, metal, in particular a CAS group I to VIIIB and IIIA of the PSE , Metal hydride, preferably sodium, magnesium, calcium, aluminum, lithium aluminum hydride, aluminum hydride, sodium borohydride (NaBH ₄ ), ascorbic acid, dihydroxyfumaric acid, phenol, derivative of phenol, hydroxy-functionalized aromatics, and / or sodium triethoxyaluminum hydride [Na (Al (OC ₂ H ₅ ) ₃ H)]. A method according to claim 11, characterized in that the composition comprising olefinically functionalized siloxane oligomers and having a content of chlorine content of not fully alkoxylated siloxanes, in particular, the composition has a content of siloxane oligomers with unreacted Si-Cl radicals and / or free chlorides on. Method according to one of claims 1 to 12, characterized in that the content of chlorine in ppm by weight of the composition containing olefinically functionalized siloxane oligomers which are substantially chlorine-free by at least 80% with respect to the compositions used in the process containing olefinically functionalized siloxane oligomers is reduced with a content of chlorine in ppm by weight. Process according to any one of Claims 1 to 13, characterized in that the composition comprising olefinically functionalized siloxane oligomers and containing chlorine is brought into contact with the reducing agent in the presence of an alcohol. Use of a reducing agent for the substitution of Si-Cl for Si-OH in compositions containing olefinically functionalized siloxane oligomers, in particular of formula I, and containing chlorine and / or for the separation of hydrolysis and / or condensation catalysts in the form of acids and / or for the separation of hydrogen chloride from compositions containing olefinically functionalized siloxane oligomers. Use of the substantially chlorine-free compositions containing one of claims 1 to 14 containing olefinically functionalized siloxane oligomers as adhesives, as crosslinking agents by graft polymerization and / or hydrolytic condensation in a conventional manner, for the preparation of polymers grafted with olefinically functionalized siloxane oligomers, prepolymers and / or mineral-filled polymers (compounds), in particular in the production of thermoplastics or elastomers, preferably of mineral-filled thermoplastics, elastomers or prepolymers thereof, for grafting or in the polymerization of thermoplastic polyolefins, as a drying agent, in particular as a water scavenger for Silicone sealing compounds, in crosslinkable polymers for the production of cables, for the preparation of crosslinkable polymers, as an oil phase in an emulsion and / or together with organosilanes or organopolysiloxanes, for the filler modification (filler coating), resin modification (additive), surface modification (functionalization, hydrophobing), as component in coating systems (in particular sol-gel systems or hybrid systems), for modifying cathodes and anode materials in batteries, as electrolyte fluid, as an additive in electrolyte fluids, for the modification of Fibers, in particular glass fibers and natural fibers, and for modifying textiles, for modifying fillers for the artificial stone industry, as building protection or constituents in building preservatives, as an additive for mineral hardening compositions, for the modification of wood, wood fibers and cellulose.