Method for producing organopolysiloxanes

Abstract

The invention relates to a continuous process for producing block copolymer organopolysiloxanes, in which in a first step chlorosilane is reacted with an alcohol to form a partial alkoxylate and in a second step chlorosilane is reacted with an alcohol to form a partial alkoxylate. The partially alkoxylated chlorosilane obtained in the first step is continuously further reacted to form a fully alkoxylated silane, which is then, in a further step, first continuously condensed with water to a low condensation degree in the presence of a catalytic trace acid and a terminal-functionalized polydiorganosiloxane, and then condensation to the desired degree of condensation in a final step by further condensation. The invention also relates to intermediates produced by said process, block copolymer organopolysiloxanes, compositions comprising intermediates and / or block copolymer organosiloxanes and their use.

Description

TECHNICAL FIELD

[0001] The present invention relates to a continuous process for producing a block-copolymer organopolysiloxane, wherein in a first step a chlorosilane is reacted with an alcohol to form a partial alkoxylate and in a second step the partially alkoxylated chlorosilane obtained in the first step is subjected to a continuous further reaction to form a fully alkoxylated silane, which in a further step is initially subjected to a continuous condensation with water to a low degree of condensation in the presence of a catalytic trace of an acid and a terminally functionalized polydiorganosiloxane and then in a final step to a further condensation to the desired degree of condensation. The present invention also relates to intermediates, block-copolymer organopolysiloxanes produced by the described process, compositions comprising the intermediates and / or block-copolymer organosiloxanes and their use.

[0002] The present invention relates to a continuous process for producing soluble reactive organopolysiloxane block-copolymers, which is particularly suitable for the controlled, gel-free condensation of highly reactive chlorosilanes or chlorosilane mixtures and which is carried out in several steps, all of which are carried out in continuous, uninterrupted succession. BACKGROUND

[0003] EP 3215554 and EP 3204443 describe processes for producing organopolysiloxanes in 3 and 2 steps, respectively, but neither of the two processes indicates that block-copolymers can be produced here. Rather, both processes are limited to the production of random copolymers obtained from monomeric precursors.

[0004] In fact, it has also been found that the block-copolymers produced according to the present invention only arise when a terminally functionalized polydiorganosiloxane is added at a specific point in the overall process, so that the processes according to EP 3215554 and EP 3204443 are not freely applicable here, but, unexpectedly, only in the case of specific embodiments, i.e. embodiments corresponding to the subject matter of the present invention, the target product of the present invention arises.

[0005] US 9076934 B2 and US 2015 / 0031841 Al teach processes for producing block-copolymers starting from polydiorganosiloxanes and silicone resins, which silicone resins are derived from at least 60 mol% or at least 80 mol% of the formula RSiO 3 / 2The unit composition. In the case of US 9076934 B2, this is carried out in the presence of a basic catalyst. A disadvantage of this process is that the polydiorganosiloxane and the resin must first be produced in separate processes so that they can then react with each other. Furthermore, the basic condensation catalysts used in US 9076934 B2 are very effective for this condensation, thus their use carries an inherently high risk of gelation and the resulting method loses robustness. Additionally, the functionalized polydiorganosiloxanes according to US 2015 / 0031841 A1 preferably do not have readily available silanol end groups, but have other functional groups such as amino, epoxy, carboxyl, oxime, or amide groups.

[0006] Furthermore, neither US 9076934 B2 nor US 2015 / 0031841 A1 teaches that the block copolymer produced according to the present invention is produced only when the terminally functionalized polydiorganosiloxane is added at specific points throughout the process.

[0007] Therefore, it is desirable to provide a continuous, economical, and sustainable method for producing block copolymer polyorganoalkoxysiloxanes from halogenated organosilanes or mixtures of halogenated organosilanes and silanol-terminated polydiorganosiloxanes, a method having characteristics such as the following: - Allows for the reproducible production of polyorganosiloxanes with constant composition from mixtures of different chlorosilanes and silanol-terminated polydiorganosiloxanes. - No inert organic solvents are used during operation; that is, only the organic components required as reactants are present in the reaction mixture. - No wastewater phase is produced. - Provides products with low residual acid content of less than 10 ppm. - Allows for selective adjustment of alkoxy content from high to low, making it suitable for providing low and high molecular weight polyorganosiloxanes up to solid products, thereby allowing for the highest degree of condensation in robust processes, and - It has a recovery rate of >95% for the released hydrohalic acids. Summary of the Invention

[0008] This objective is achieved through the present invention. It cannot be achieved through freely chosen combinations of existing methods. Otherwise, there will always be unrealized sub-aspects, particularly in that co-condensation will not proceed to a sufficient degree.

[0009] Surprisingly, successful results were achieved solely through the method of the present invention, namely, the following combination: a reaction unit comprising a column connected to a pre-reactor and subsequently to another reactor, also designed for continuous operation, as a further reaction unit. This method, when operated in a suitable manner, allows the objectives of the invention to be achieved, and in doing so, all the aforementioned sub-aspects are accomplished.

[0010] Therefore, this objective is achieved by the method of the present invention for the continuous production of block copolymer polyorganoalkoxysiloxanes, the method comprising the following steps in the order stated: (i) Reacting at least one chlorosilane with an alcohol or a mixture of alcohols in a pre-reactor to form a reaction mixture containing a partial alkoxylate, (ii) The reaction mixture obtained after step (i) is transferred to a first reaction unit connected to a pre-reactor and comprising a tower having an upper end, a lower end, and an infeed point. This transfer is achieved by transferring the reaction mixture to the tower via the feed point. The feed point of the column is set such that the reaction mixture is fed into the middle third of the column's total length. (iii) The reaction mixture transferred to the column in step (ii) is conveyed within the column, which proceeds downwards under gravity. In this process, a portion of the alkoxylate is combined with another alcohol or a further mixture of alcohols. Before the reaction mixture reaches the lower part of the column, the portion of the alkoxylate reacts to form a complete alkoxylate, which is located no more than 25% of the total length of the column. This complete alkoxylate is then present at the column bottom. (iv) The fully alkoxylated compound in the lower part of the column of the first reaction unit is reacted with another alcohol or a mixture of other alcohols, water, and at least one silanol-terminated polydiorganosiloxane to form a low-condensation polyorganosiloxane mixture (crude mixture), which may contain volatile components. (v) The crude mixture obtained after step (iv) is transferred to a second reaction unit connected to the first reaction unit and including an additional continuous reactor, thereby achieving the transfer to the additional continuous reactor, and (vi) The crude mixture transferred in step (v) is reacted with another alcohol or a mixture of other alcohols and with water to form a polyorganosiloxane mixture having a higher degree of condensation than the crude mixture.

[0011] To keep the page count of this specification within limits, preferred embodiments of each feature are described below.

[0012] However, expert readers should clearly understand this disclosure as meaning that any combination of different levels of preference is also explicitly disclosed and expected.

[0013] In step (i), preferably, 0.1 to 0.9 mol of alcohol is used per mol of hydrolyzable chlorine from the chlorosilane. These molar ratios mean that the chlorosilane is not fully alkoxylated, but rather initially reacts to form partially alkoxylated compounds.

[0014] According to the present invention, "partially alkoxylated products" refer to the reaction products of chlorosilanes and alcohols, wherein some chlorine substituents of the chlorosilanes have been replaced by alkoxy substituents.

[0015] According to the present invention, a “fully alkoxylated product” refers to the reaction product of a chlorosilane and an alcohol, wherein substantially all chlorine substituents of the chlorosilane have been replaced by alkoxy substituents.

[0016] According to the invention, the "degree of condensation" relates to the molecular weight and the number of remaining condensable groups, wherein the difference between a higher degree of condensation and a lower degree of condensation is that the molecular weight is higher at a higher degree of condensation and the number of remaining condensable groups is lower at a higher degree of condensation.

[0017] In the method of the present invention, it is possible that in step (i) some chlorosilane molecules, preferably all chlorosilane molecules, have been completely alkoxylated, and therefore it is not a partial reaction, but a complete reaction that already exists.

[0018] Step (iii) of the method of the present invention is preferably used to react chlorosilane molecules that have not yet fully reacted to form a complete alkoxylated product to form a complete alkoxylated product.

[0019] Preferably, at the end of step (iii) of the method, at least 90% by weight of the chlorosilane used has reacted to form a fully alkoxysilane, preferably at least 95% by weight, and particularly at least 99% by weight.

[0020] The method of the present invention is particularly advantageous because it is a continuous method in which all steps are performed in a continuous and uninterrupted sequence. In this case, for example, partial reaction (i), transfer (ii), delivery (iii), reaction (iv), transfer (v), and reaction (vi) are carried out sequentially.

[0021] The continuous reactor in the second reaction unit can be designed as a loop reactor.

[0022] The method of the present invention has the following special characteristics: apart from the alcohol required for the reaction, no other organic components are used in the entire method, preferably no other low molecular weight components are used, and in particular no inert organic solvents are used.

[0023] In one particular embodiment, only one specific alcohol is used in each method step, rather than a mixture of different alcohols. Particularly preferably, the alcohol is the same in all method steps.

[0024] If the silanol-terminated polydiorganosiloxane is not used at the designated site in the column, but only in the downstream continuous reactor (which may be a loop reactor), then insufficient co-condensation of the silanol-terminated polydiorganosiloxane with the silicone resin unit formed from the silane monomer (derived from chlorosilane) will occur, or it will not occur at all. The result is a two-phase mixture in which the silanol-terminated polydiorganosiloxane is recovered almost quantitatively as a second phase. Surprisingly, it was then also found that when the silanol-terminated polydiorganosiloxane has been used together with the silane monomer that produces the resin in the pre-reactor, the reaction between the silanol-terminated polydiorganosiloxane and the silane monomer that forms the resin is insufficient. Only the method of the present invention meets this criterion.

[0025] The alcohol used can be of industrial grade and therefore contains a small amount of water, but preferably must contain no more than 5% water by weight. Furthermore, water is not used in the pre-reactor. Water in the pre-reactor is undesirable and can even be harmful. This method does tolerate amounts of water present in industrial alcohols up to a maximum of 5% by weight. Depending on the silane mixture chosen, larger amounts of water above this limit can be tolerated. However, this is no longer universally applicable.

[0026] If the product contains volatile components, it is preferable to remove the volatile components by devolatileization, and then leave them in their final form. The devolatileization process can be varied as desired, and all processes are within the scope of known prior art. Examples of suitable variations are described in more detail below. The distillate obtained by devolatileization (i.e., removal of volatile components from the product) of the product downstream of a second reaction unit (i.e., for example, downstream of a loop unit of a column) contains volatile components from the product.

[0027] The improved space-time performance described in DE 10 2005 003 898 through the use of a pre-reactor is also achievable in the present invention, since most of the released hydrogen chloride (which is a limiting factor for the production of the first reaction unit) has already been formed and discharged in the pre-reactor, thereby reducing the load on the downstream tower.

[0028] Preferably, the alcohol used for the partial reaction of chlorosilanes in the pre-reactor is a distillate from the first and / or second reaction unit, which is returned to the pre-reactor as a distillate or gas. It must be observed that the residual water content is set at a maximum of 5% by weight.

[0029] In the pre-reactor and prior to its introduction, the distillate can be mixed with additional alcohols and homogenized via a short mixing section. Pure alkoxylation is preferably carried out in the pre-reactor without subsequent condensation, which is why anhydrous or at least very low-water operating modes are preferred.

[0030] The alcohol used is preferably a hydrocarbon compound having a hydroxyl group, used to produce alkoxysilanes or organopolysiloxanes by reacting a chlorosilane with an alcohol and optionally water, and its boiling point is lower than that of the corresponding alkoxysilane or organopolysiloxane to be produced. Alkyl alcohols having 1 to 6 carbon atoms and ether-oxy-substituted alkyl alcohols, such as methanol, ethanol, n-propanol, isopropanol, 2-methoxyethanol, n-butanol, or n-hexanol, are preferred in each case. Methanol, ethanol, isopropanol, and butanol are particularly preferred, especially methanol and ethanol. Mixtures of different alcohols may also be used.

[0031] In this method, the hydrogen chloride formed preferably has its condensable components removed at the top of the pre-reactor and at the top of the first reaction unit, and these components are returned to the appropriate reaction unit. The hydrogen chloride is thus recoverable as a gas.

[0032] The chlorosilanes used are preferably the same chlorosilanes already used to produce alkoxysilanes or organopolysiloxanes by reacting chlorosilanes with alcohols and optionally water. These are particularly silanes of general formula (1).

[0033] R n SiCl 4-n (1), in R represents a hydrogen group or an acid-stable C1-C18 hydrocarbon group, preferably a C1-C10 hydrocarbon group, more preferably a C1-C6 hydrocarbon group, optionally substituted with at least one heteroatom, and n can have values ​​of 0, 1, 2, or 3.

[0034] In the preferred embodiment of equation (1), the following limitations apply: In at most 50 mol% of the silane of formula (1), n ​​has a value of 3, and n has a value of 0 or 1 in at least 20 mol% of the silane of formula (1).

[0035] Heteroatoms are selected from O, S, N and P, especially O and N.

[0036] In all the formulas of this invention, the symbols are defined independently of each other. Silicon atoms are always tetravalent.

[0037] Examples of the choice of hydrocarbon group R are alkyl groups, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl groups, hexyl groups (such as n-hexyl groups), heptyl groups (such as n-heptyl groups), octyl groups (such as n-octyl groups), and isooctyl groups (such as 2,2,4-trimethylpentyl groups), nonyl groups (such as n-nonyl groups), decyl groups (such as n-decyl groups), dodecyl groups (such as n-dodecyl groups), and octadecyl groups (such as n-octadecyl groups); cycloalkyl groups, such as cyclopentyl, cyclohexyl, cycloheptyl, and methylcyclohexyl groups; aryl groups, such as phenyl, naphthyl, anthracene, and phenanthrene groups; alkylaryl groups, such as tolyl, xylyl, and ethylphenyl groups; and aralkyl groups, such as benzyl and β-phenylethyl groups. Particularly preferred hydrocarbon groups R are methyl, n-propyl, and phenyl groups.

[0038] The silanes of formula (1) can be used as pure silanes or as a mixture of different silanes of formula (1) to react with alcohols in a pre-reactor to form partially alkoxylated compounds. Additional chlorosilanes of formula (1) that are not fed into the pre-reactor for partial alkoxylation can also be used in this method. These are fed directly into the first reaction unit, i.e., into the column, with the feed located at the middle third of the column's total length.

[0039] This process can be used when different silanes of formula (1) react with each other, the different silanes having significantly different boiling points and potentially different reactivity, and these differences cannot be adequately compensated for by partial alkoxylation in a pre-reactor. In this process, the higher-boiling-point silane of formula (1) is always fed into the first reaction unit, while the lower-boiling-point silane of formula (1) is fed into the pre-reactor for partial alkoxylation.

[0040] The partially alkoxylated derivatives formed by the partial alkoxylation of the lower-boiling silanes of formula (1) have higher boiling points than the silanes of formula (1) themselves, thus adjusting the boiling points of different silanes. Therefore, when using silanes of formula (1), it is preferable to use a process that uses silanes with boiling points lower than or within the boiling point range of the corresponding alcohols used, and due to their low boiling points, they are expected to be discharged from the tower, resulting in a product composition that does not correspond to the stoichiometry used. To counteract this, the amount of low-boiling silanes can be increased to compensate for the loss, but this makes the method less cost-effective and generates a higher amount of waste. As a result of the discharge of chlorosilanes of formula (1), siliceous material can accumulate in the equipment due to the formation of insoluble crosslinking condensation products in the exhaust gas stream and in the scrubber. The generalized process avoids these problems. Since the most reactive Si-Cl bond reacts first during the partial alkoxylation process, this step also aligns the reactivity of the different chlorosilanes of formula (1).

[0041] In cases where different chlorosilanes of formula (1) that can react with each other have significantly different reactivity, reactivity can be aligned through the same process, wherein the reactivity of the higher reactivity of formula (1) and the possibly lower boiling point chlorosilane is reduced by partial alkoxylation formation, and the lower reactivity and higher boiling point silane of formula (1) are fed into the first reaction unit. The result is a better random distribution of different silane structural units in the resulting polyorganosiloxane.

[0042] In the context of this invention, the term block copolymer organopolysiloxane refers to a product containing linear D units arranged in chains (R... 1 2SiO 2 / 2 ) and crosslinked T units (R 2 SiO 3 / 2 The organopolysiloxanes are such that they mainly have the composition of formula (2): (R 1 2SiO 2 / 2 ) a (R 2 SiO 3 / 2 ) b (2).

[0043] The organopolysiloxanes of the present invention differ in this respect from random copolymers, in which D units and T units alternate arbitrarily and do not form a preferred ordered structure in the form of discrete blocks.

[0044] In the case of random copolymers, the formation of block structures is not completely ruled out, but occurs only to a degree that is possible within the limits of statistical probability. Block formation here is of sufficiently small importance that it does not have a decisive influence on the properties of the obtained polyorganosiloxane.

[0045] In contrast, the "block copolymer organopolysiloxane" of the present invention should be understood to refer to those in which the D units are connected together in a direct and uninterrupted sequence, primarily in the form of oligomeric or polymeric chains having a chain length of at least four D units. Depending on the chain length of the silanol-terminated polydiorganosiloxane used, the chain length can be as high as 400, preferably in the range of 4 to 200, more preferably in the range of 4 to 100, and particularly in the range of 4 to 75. These are linear blocks of the polyorganosiloxanes of the present invention.

[0046] The nonlinear T-units then form blocks consisting of at least 4, preferably at least 6, more preferably at least 8, and especially at least 10 T-units in an uninterrupted sequence, wherein the nonlinear blocks can then be cross-linked with each other.

[0047] The tags a and b are defined based on the above.

[0048] Group R 1 and R 2 Each of these is a group R as defined above, and each is independent of the others.

[0049] In addition to unit (R) 1 2SiO 2 / 2 ) a and (R) 2 SiO 3 / 2 ) b In addition, the polyorganosiloxane of the present invention can include units of formula (3) in a nonlinear block composed of T units.

[0050] R 2 c R 3 d SiO (4-c-d) / 2 (3), in R 2 It is as defined above. R 3 The condensable group of the form -OR, where R is as defined above, and c represents the number 1, and c + d can take the values ​​1, 2 or 3, where d represents the value 0, 1 or 2.

[0051] The "condensation-capable group" has the following specific characteristics: the siloxane is capable of undergoing a condensation reaction, wherein the condensation-capable group is preferably (to some extent) removed.

[0052] The polyorganosiloxane of the present invention contains a total of 5-75 mol%, preferably 5-60 mol%, more preferably 5-50 mol%, and particularly 5-40 mol% of D units (R) arranged in linear blocks. 1 2SiO 2 / 2 ).

[0053] The polyorganosiloxane of the present invention contains a total of 25-95 mol%, preferably 40-95 mol%, more preferably 50-95 mol%, and particularly 60-95 mol% of T units (R). 2 SiO 3 / 2 ), optionally in a mixture of units with those of Equation (3), the T units are arranged in nonlinear blocks.

[0054] In principle, randomly distributed D units can also exist, provided that equation (R) holds true. 1 The corresponding chlorosilanes of 2SiCl2 have been used to meter the chlorosilane mixture entering the pre-reactor. Since this arrangement of the D units can also be achieved by other methods in the prior art, it is not necessary to distinguish it from existing technologies here, nor is it preferred.

[0055] Suitable silanol-terminated or silanol-functionalized polydiorganosiloxanes are those of formula (4): HO-(R 2 2SiO 2 / 2 ) e -OH (4), Where R 2 The group R represents the number having a value of 4 to 2000, preferably 5 to 1800, particularly 5 to 1500, and especially preferably 5 to 1000. Silanol-functionalized polydiorganosiloxanes having an average chain length e of 8 to 100 have been found to be particularly suitable.

[0056] Although apart from unit (R) 1 2SiO 2 / 2 ) a and (R) 2 SiO 3 / 2 ) b In addition, other siloxane units may exist, as described below, unit (R 1 2SiO 2 / 2 ) a and (R) 2 SiO 3 / 2 ) bThe predominant presence and described arrangement and extent of these are absolute prerequisites for the inventiveness of the polyorganosiloxanes under consideration. This predominantly refers to the presence of at least 70 mol%, preferably at least 75 mol%, particularly at least 80%, and very particularly at least 85% of the total siloxane units leading to the formation of the polyorganosiloxanes of the present invention, in the described block copolymer arrangement.

[0057] The pre-reactor can consist, for example, of a stirred tank reactor, a tubular reactor, or a loop reactor (with or without forced circulation). In the case of a pure alkoxylation reaction, while forced circulation is not harmful, it is not necessary either, as the hydrogen chloride released during the reaction is sufficient to ensure adequate circulation and mixing. In the case of additional metered water addition, forced circulation is preferred, and pre-reactors with a very thorough mixing tendency (e.g., loop reactors) are particularly preferred.

[0058] The pre-reactor is preferably fed with a liquid chlorosilane of formula (I) or a mixture of chlorosilanes, in which up to 80 mol% of Si-bonded chlorine units undergo a reaction with alcohol hydroxyl groups.

[0059] Once the condensable components have been removed by cooling brine, the hydrogen chloride gas released in the pre-reactor is preferably vented and recycled. For example, the condensed components are returned to the pre-reactor.

[0060] The pre-reactor is preferably operated at a temperature below the boiling point of the chlorosilane or mixture of chlorosilanes used.

[0061] Part of the reaction mixture is transferred to the column of the first reaction unit, fed into the column at the middle third of the column's height, preferably in the upper middle third region. This can be done, for example, by an overflow device.

[0062] In the first reaction unit, further mixing and reaction of the reaction mixture from the pre-reactor initially occur only with alcohols, particularly with alcohols preferably flowing countercurrently from the bottom up in the column, the alcohol or alcohol mixture used for this purpose preferably being the same as that previously used in the pre-reactor. Here, the reaction mixture reacts via additional silicon-bonded chlorine atoms, which are removed and replaced with alkoxy groups obtained by removing hydrogen from the alcohol used. The hydrogen groups removed from the alcohol and the chlorine groups removed from the silicon react to form hydrogen chloride molecules. In this way, the reaction mixture from the pre-reactor produces almost completely alkoxylated products as it is fed into the lower part of the column (the so-called bottom of the column), which preferably comprises at most 25% of the height of the column.

[0063] At the bottom of the column, the almost completely alkoxylated compound encounters another alcohol, water, and a polydiorganosiloxane of formula (4) with silanol end-capping. A catalytic amount of hydrochloric acid is also present at the bottom of the column, preferably 5 to 2000 ppm based on the weight of the siloxane present at the bottom of the column, more preferably 5 to 1500 ppm, and particularly 5 to 1000 ppm.

[0064] The mixture present at the bottom of the tower forms a liquid crude product.

[0065] Once the condensable components have been removed, the hydrogen chloride gas generated in the tower is preferably discharged from the reactor and recycled. After ensuring that the amount of water meets the previously described requirements, the condensable components, cooled with brine, are transferred to the pre-reactor. Optionally, another chlorosilane of formula (I) or a mixture of chlorosilanes of chlorosilanes is added directly to the first reaction unit and similarly undergoes a reaction with the reaction mixture from the pre-reactor, alcohol, water, and the silanol-terminated polydiorganosiloxane of formula (4).

[0066] Preferably, the temperature of the column in the first reaction unit does not exceed 120°C. More preferably, the temperature in the column does not exceed 100°C.

[0067] The crude liquid organopolysiloxane product from the first reaction unit has a low degree of condensation with high alkoxy content and low viscosity as a pure isolated product.

[0068] The alkoxy group content of the pure devolatile organopolysiloxane downstream of the first reaction unit is >20% by weight, preferably >22% by weight, and particularly >25% by weight.

[0069] In each case at 25°C, the viscosity of the separated devolatile organopolysiloxane downstream of the first reaction unit is < 600 mPa·s, particularly < 500 mPa·s, especially < 400 mPa·s.

[0070] The amount of silicon-bonded chlorine in the organopolysiloxane reaction product from the first reaction unit is less than 100 ppm, preferably less than 75 ppm, particularly less than 50 ppm, and especially preferably less than 30 ppm.

[0071] The reaction mixture containing liquid organopolysiloxane from the first reaction unit is transferred to a second reaction unit comprising a continuous reactor (e.g., a loop reactor). In this second continuous reaction unit, the reaction mixture from the first reaction unit is further mixed with additional alcohol, hydrogen chloride, and water and undergoes condensation to the desired degree of condensation. Preferably, in various cases, based on 100 parts by weight of pure devolatile organopolysiloxane from the first reaction unit, the mixture in the second continuous reaction unit comprises 4 to 17 parts by weight, more preferably 5 to 14 parts by weight of water, 40 to 120 parts by weight, more preferably 50 to 100 parts by weight of alcohol, and 0.02 to 0.2 parts by weight, more preferably 0.04 to 0.15 parts by weight of hydrogen chloride.

[0072] Additional alkoxy and / or hydroxyl-functionalized organopolysiloxanes or alkoxy and / or hydroxyl-functionalized silanes may be metered and added to the second reaction unit. These additional alkoxy and / or hydroxyl-functionalized organopolysiloxanes or alkoxy and / or hydroxyl-functionalized silanes are preferably liquids, or they may be soluble in an alcohol or mixture of alcohols used to produce the partially alkoxylated compounds in the pre-reactor.

[0073] Additional further alkoxy and / or hydroxyl functionalized organopolysiloxanes are those composed of repeating units of formula (5): R p Si(OR 4 ) q O (4-p-q) / 2 (5), In the unit of equation (5) R is as defined above. R 4 Indicates the same or different monovalent C1-C6 alkyl groups or hydrogens. In the unit of equation (5), p and q can have values ​​of 0, 1, 2, or 3, provided that... P + q ≤ 3, and In all repeating units of equation (5), p has a value of 1 in at least 20%, preferably at least 30%, and more preferably at least 40%.

[0074] Additional alkoxysilanes have the general formula (6): R 5 o Si(OR 4 ) 4-o (6), in R 5 It is a hydrocarbon group that is optionally substituted with heteroatoms but does not contain any nitrogen atoms. R 4It is as defined above, and o represents a number with a value of 0, 1, 2, or 3.

[0075] Several patents describe the condensation of alkoxysilanes and chlorosilanes into organopolysiloxanes in a continuous process, in some cases including in a loop, but these patents all employ polar (e.g., DE 954198) or nonpolar solvents (see DE 19800023, EP 3016994). In contrast, in the present invention, without the addition of additional polar or nonpolar solvents, further hydrolysis and condensation of the alkoxy-functionalized liquid organopolysiloxane from the first reaction unit are carried out using only an alcohol or mixture of alcohols as reactants to obtain an organopolysiloxane with the desired high degree of condensation.

[0076] It has been found particularly advantageous to meter the addition of silanol-terminated polydiorganosiloxanes to the bottom of the column within the first reaction unit.

[0077] If the silanol-terminated polyorganosiloxane of formula (4) is not metered into the bottom of the column as described, but is instead metered into a second continuous reaction unit (which may include, for example, a loop reactor), then an insufficient condensation occurs between the polydiorganosiloxane of formula (4) and the crude product from the bottom of the column, resulting in a physical mixture of the polydiorganosiloxane of formula (4) and the crude condensation product from the bottom of the column in a possible equilibrium form. If the polydiorganosiloxane of formula (4) is added directly to the chlorosilane mixture metered into the pre-reactor, or if it is metered separately from the portion of the alkoxylated product from the pre-reactor into a portion of the column located above the portion of the column described as the bottom of the column, gel particles gradually form and deposit in the column. Furthermore, a non-uniform bottom product is obtained. Detailed Implementation

[0078] The performance of the method of the present invention on an exemplary apparatus (not limited thereto) is described below, which is also used in the following embodiments. The apparatus includes a pre-reactor, a column with a circulating evaporator, and a loop. The pre-reactor is also a loop reactor with a centrifugal pump that is valve-controlled and pumps the liquid contents in maximum turbulent circulation.

[0079] Silyl chloride and distillate from a second reaction unit, including a loop reactor, are metered at the bottom into a pre-reactor. Optionally, an alcohol is metered into the distillate, and the mixture is homogenized via a short mixing section. The contents of the pre-reactor are transferred to the first reaction unit via an overflow device.

[0080] The pre-reactor has an outlet at the top for releasing hydrogen chloride gas. This gas passes through a water condenser and then a brine condenser, where condensable components are removed and returned directly to the pre-reactor. Hydrogen chloride gas obtained downstream of the condensers can be recovered.

[0081] The first reaction unit consists of a circulating evaporator and a column mounted thereon. The column of the first reaction unit first has a water-operated condenser at the top, followed by a brine-operated condenser. The distillate obtained is fed back into the column. Hydrogen chloride gas obtained downstream of the condenser can be recovered.

[0082] The second reaction unit consists of a loop or stirred batch reactor (with continuous inflow and outflow). Another variant is discontinuous post-condensation in a batch reactor.

[0083] The same amount of reaction mixture as obtained by the reaction is continuously discharged from the circulating evaporator of the first reaction unit via a centrifugal pump. The reaction mixture from the circulating evaporator of the first reaction unit is metered into the loop of the second reaction unit as a mixture with additional water, optionally ethanol, and a catalytic amount of hydrochloric acid or chlorosilane. The product is removed from the second reaction unit to the extent that it was formed.

[0084] The organopolysiloxanes obtained from the first reaction unit, including the tower, can be obtained as a pure, stable product through standard purification measures, including filtration, distillation, and blending, or formulated into preparations with other components. In addition to other silicon-containing components, components that can be used to produce preparations include organic monomers or organic polymers, water, solvents, auxiliaries such as emulsifiers, stabilizers, pH adjusters or other additives, fillers, pigments, and building materials; this list should be understood as merely examples and not as limitations.

[0085] Since these organopolysiloxanes are intermediates throughout the process, for better distinction and clarity of language, they are referred to hereinafter as silicone resin intermediates; this terminology is chosen purely rhetorically to a reasonable degree and does not imply any limitation on the content. The silicone resin intermediates from the first reaction unit are silicone resin intermediates formed from repeating units of formula (7): R 6 x Si(OR 7 ) y O (4-x-y) / 2 (7), In the unit of equation (7), R 6 Represents group R, Where R 7 For R 4 Defined In equation (7), x represents the value 1 or 2, and In the unit of equation (7), y can have the values ​​0, 1, 2, or 3, provided that... x + y ≤ 4, and x has a value of 1 in at least 30%, preferably at least 40%, and more preferably at least 50%, particularly in 70 ± 5% of all repeating units in equation (7), and a value of 2 in at least 5%, particularly in at least 10%, more preferably at least 15%, particularly in 30 ± 5%. Among them, the repeating unit of equation (7) (where x has a value of 2) can have at most one equation OR 7 The group, such that in these repeating units, y = 0 or 1, the repeating units are further linked together to form a segment of at least four repeating units in an uninterrupted sequence. The silicone resin intermediates composed of repeating units of formula (7) are specifically characterized in that they contain at least 15% by weight of OR groups. 7 Preferably, it is at least 18% by weight, more preferably at least 20% by weight, and particularly at least 22% by weight. In the silicone resin intermediate composed of repeating units of formula (7), unit OR 7 This indicates a hydroxyl content of up to 10% by weight, preferably up to 9% by weight, more preferably up to 8% by weight, and particularly up to 7% by weight.

[0086] Although silanol groups are not necessarily required to be present in the silicone resin intermediates consisting of repeating units of formula (7), the chosen reaction conditions, particularly the presence of water and acid, generally imply their presence. Where x = 1 and y = 3, such that x + y = 4, it is not a repeating unit of the present polyorganosiloxane, but rather a monomeric trialkoxysilane. In the intermediates from the first reaction unit, the chosen low degree of condensation implies that the formation of such monomers must be accepted. This does not constitute a limitation on the condensation reaction in the second reaction unit, in which these monomers are incorporated into the polyorganosiloxane final product downstream of the second reaction unit. Because it would be inaccurate to refer to the monomers as repeating units of the polyorganosiloxane in this case, it should be noted here that these monomers are covered by repeating units according to formula (7).

[0087] The silicone resin intermediates preferably have an average molecular weight in the range of 600 to 3000 g / mol (weight average) and a polydispersity of up to 8. Preferably, they have an average molecular weight of 650-2900 g / mol and a polydispersity of 7; more preferably, they have an average molecular weight of 700-2800 g / mol and a polydispersity of 6; particularly, they have an average molecular weight of 700-2600 g / mol and a polydispersity of 5. As pure products, they are particularly liquids, and at 25°C and standard pressure, their viscosity is preferably in the range of 10 to 600 mPa·s, more preferably 25 to 550 mPa·s, and particularly preferably 30 to 500 mPa·s.

[0088] Organopolysiloxanes obtained from a second reaction unit, including, for example, a loop reactor, can be obtained as pure, stable products through standard purification measures, including steps of filtration, distillation, and blending, or formulated with other components. As isolated pure products, the organopolysiloxanes from the second reaction unit are liquids, high-viscosity products, or solids, depending on the degree of condensation they undergo. The degree of condensation obtained depends on the reaction conditions selected in the second reaction unit. Specifically, the degree of condensation is determined by the amount of water, acid, and temperature, and also by the type of acid selected and the order and rate of its addition to the second reaction unit. In principle, any combination of these parameters is conceivable, and the choice of these parameters affects the desired result. Since the method is the subject of this invention in terms of its overall variability, possible combinations are not excluded in principle, except for those combinations that are obviously meaningless, because it is apparent from the known prior art that they do not lead to the production of soluble or fusible organopolysiloxanes that can be further processed accordingly. What is surprising about this method is that, compared with existing technologies, it can achieve variability and the resulting product diversity without the use of polar or nonpolar organic solvents, in addition to alcohols or mixtures of alcohols already used in pre-reactors.

[0089] Based on 100 parts by weight of pure devolatile organopolysiloxane from the first reaction unit, when the mixture contains 4 to 10 parts by weight of water, a liquid to viscous product is preferably obtained.

[0090] Based on 100 parts by weight of pure devolatile organopolysiloxane from the first reaction unit, when the mixture contains 10 to 17 parts by weight of water, a viscous to solid product is preferably obtained.

[0091] The water is preferably partially demineralized water, completely demineralized water, distilled or (multiple) redistilled water, and water used for medical or pharmaceutical purposes, more preferably partially demineralized water and completely demineralized water.

[0092] Preferably, the water used according to the invention has a conductivity of less than 50 µS / cm at 25°C and 1010 hPa. The water used according to the invention is preferably air-saturated, clear, and colorless.

[0093] The alcohol is preferably the same alcohol used in the first reaction unit, i.e., methanol or ethanol. Ethanol may contain common denaturing agents such as methyl ethyl ketone, petroleum ether, or cyclohexane, with methyl ethyl ketone being preferred.

[0094] Hydrogen chloride can be added in the form of hydrochloric acid or precursors such as chlorosilanes, acyl chlorides or linear phosphonitrile chlorides, preferably hydrochloric acid solutions and especially aqueous hydrochloric acid solutions.

[0095] The components are preferably metered individually, briefly mixed, and then metered into the loop. In the case of a closed loop, the components can also be metered and added individually upstream of the circulation pump.

[0096] The closed loop is preferably operated at an absolute pressure of 1 to 5 bar, a temperature 5 to 10 K below the boiling point, an average residence time of 10 to 150 min, and in laminar to turbulent flow.

[0097] The stirred batch reactor is preferably operated with continuous inflow and outflow at an absolute pressure of 1 bar, a boiling temperature of the mixture, and an average residence time of 20 to 100 min. The average residence time is calculated by dividing the reaction volume by the rate of product removal.

[0098] Components that can be used to produce formulations comprising organopolysiloxanes from a second reaction unit include, in addition to other liquid or solid silicon-containing components, organic monomers or organic polymers, water, solvents, auxiliaries such as emulsifiers, stabilizers, pH adjusters or other additives. This list is to be understood as examples only and not as a limitation.

[0099] The organopolysiloxane from the second reaction unit is an organopolysiloxane formed from the repeating unit of formula (8): R 6 f Si(OR 7 ) g O (4-f-g) / 2 (8) In the unit of equation (8), R 6 and R 7 As defined above, In the unit of equation (8), f and g can have values ​​of 0, 1, 2, or 3, provided that f + g ≤ 3, and f has a value of 1 in at least 30%, preferably at least 40%, and more preferably at least 50%, particularly 70 ± 5% of all repeating units in equation (7), and a value of 2 in at least 5%, particularly at least 10%, more preferably at least 15%, particularly 30 ± 5%, wherein the repeating units are further linked together to form a chain segment of at least four repeating units in an uninterrupted sequence. In all repeating units of general formula (8), the average g has an average value of 0.05 to 1.7, preferably 0.06 to 1.6, and more preferably 0.08 to 1.5, wherein The silicone resin intermediates composed of repeating units of formula (8) are characterized in that they contain up to 20% by weight of OR groups. 7 Preferably, it is up to 18% by weight, more preferably up to 16% by weight, and particularly up to 14% by weight. In the organopolysiloxane composed of repeating units of formula (8), the unit OR 7 This indicates a maximum of 10% by weight, preferably a maximum of 9% by weight, more preferably a maximum of 8% by weight, and particularly a maximum of 7% by weight of hydroxyl groups.

[0100] The silanol group does not necessarily have to be present in the organopolysiloxane composed of repeating units of formula (8). In the organopolysiloxane composed of repeating units of formula (8), there is always at least 5% less (by weight) of the group OR compared to the corresponding silicone resin intermediate composed of repeating units of formula (7). 7 Preferably at least 7%, more preferably at least 10% by weight, particularly at least 12% by weight, wherein in this case 100% by weight of the OR group 7 It is a group OR derived from the repeating unit of formula (7) of the silicone resin intermediate. 7 The total number.

[0101] The organopolysiloxanes composed of repeating units of formula (8) preferably have an average molecular weight in the range of 1,000 to 50,000 g / mol (weight average) and a polydispersity of up to 20. Preferably, they have an average molecular weight of 1,250-30,000 g / mol and a polydispersity of 18; more preferably, they have an average molecular weight of 1,500-20,000 g / mol and a polydispersity of 15; particularly, they have an average molecular weight of 1,500-15,000 g / mol and a polydispersity of 13. The average molecular weight of the organopolysiloxanes composed of repeating units of formula (8) is here at least 1.1 times, preferably at least 1.2 times, more preferably at least 1.3 times, and particularly at least 1.4 times that of the silicone resin intermediates composed of repeating units of formula (8). Because the organopolysiloxanes composed of repeating units of formula (8) can be liquids and high-viscosity or solids, they can span a very wide viscosity range. In the case of liquid organopolysiloxanes, at 25°C and standard pressure, their viscosity is preferably > 600 mPa·s, more preferably > 750 mPa·s, and even more preferably > 1000 mPa·s.

[0102] Organopolysiloxanes obtained from the second reaction unit, including a loop reactor, can be obtained as pure, stable products through standard purification measures, including filtration, distillation, and blending, or formulated into formulations with other components. In addition to other silicon-containing components, components that can be used to produce formulations include organic monomers or organic polymers, water, solvents, auxiliaries such as emulsifiers, stabilizers, pH adjusters or other additives, fillers, pigments, and building materials; this list should be understood as merely examples and not as limitations.

[0103] The silicone resin intermediates produced according to the method of the present invention and consisting of repeating units of formula (7) or organopolysiloxanes consisting of repeating units of formula (8) and formulations available therefrom are well suited for use as corrosion protection formulations.

[0104] The present invention further provides a formulation comprising at least one silicone resin intermediate consisting of repeating units of formula (7) and / or at least one block copolymer polyorganoalkoxysiloxane consisting of repeating units of formula (8) and at least one auxiliary agent.

[0105] Additives may be selected from emulsifiers, biocides, water, fillers, pigments, and pigment wetting and dispersing agents.

[0106] The present invention thus further provides the use of silicone resin intermediates composed of repeating units of formula (7), block copolymer polyorganoalkoxysiloxanes composed of repeating units of formula (8), or formulations of the present invention for corrosion protection (as corrosion protection).

[0107] They are particularly suitable for corrosion protection at high temperatures.

[0108] In addition to the purpose of high-temperature corrosion resistance, the silicone resin intermediates produced according to the method of the present invention and composed of repeating units of formula (7) or organopolysiloxanes composed of repeating units of formula (8), and the formulations thereof, can also be used for corrosion protection of reinforcing bars in reinforced concrete. The silicone resin intermediates according to the present invention composed of repeating units of formula (7) or organopolysiloxanes composed of repeating units of formula (8) and the formulations thereof, can be used for this purpose, either in pure form or in the form of formulations. Then, not only before the concrete mixture is formed and cured, when the silicone resin intermediates according to the present invention composed of repeating units of formula (7) or organopolysiloxanes composed of repeating units of formula (8) and the formulations thereof, which are available therein, are introduced into the concrete mixture, but also after the concrete has cured, when the compounds of the present invention or the formulations thereof are applied to the surface of the concrete, the corrosion inhibition effect in reinforced concrete is achieved.

[0109] Silicone resin intermediates consisting of repeating units of formula (7) or organopolysiloxanes consisting of repeating units of formula (8) and formulations available therefrom can be used as adhesives for the production of artificial stone for indoor and outdoor use.

[0110] In addition to corrosion protection on metals, the silicone resin intermediate produced according to the method of the present invention and composed of repeating units of formula (7) or organopolysiloxane composed of repeating units of formula (8) and formulations thereof can also be used to manipulate additional properties of formulations comprising the silicone resin intermediate produced according to the method of the present invention and composed of repeating units of formula (7) or organopolysiloxane composed of repeating units of formula (8) and formulations thereof, or a solid body or film obtained from a formulation comprising the silicone resin intermediate produced according to the method of the present invention and composed of repeating units of formula (7) or organopolysiloxane composed of repeating units of formula (8) and formulations thereof, for example: - Controlling conductivity and resistance, - Control the leveling properties of the formulation. - To control the gloss of wet or cured films or products. - Increase weather resistance - Increase chemical resistance - Increase color stability, - Reduce the tendency to chalk. - Reduce or increase the static and sliding friction of formulations of the present invention comprising repeating units of formula (7) or repeating units of formula (8) and of solids or films obtained from formulations thereof. - To stabilize or destabilize the foam in the formulation, said formulation comprising the silicone resin intermediate of the present invention consisting of repeating units of formula (7) or an organopolysiloxane consisting of repeating units of formula (8) and formulations available therefrom. - To improve the adhesion of formulations comprising a silicone resin intermediate composed of repeating units of formula (7) or an organopolysiloxane composed of repeating units of formula (8) produced according to the method of the invention, and formulations available therefrom, to a substrate, wherein the formulations comprising a silicone resin intermediate composed of repeating units of formula (7) or an organopolysiloxane composed of repeating units of formula (8) produced according to the method of the invention, and formulations available therefrom, are applied to or between said substrates. - Control the wetting and dispersing properties of fillers and pigments, - Controlling the rheological properties of a formulation comprising a silicone resin intermediate produced according to the method of the invention and composed of repeating units of formula (7) or an organopolysiloxane composed of repeating units of formula (8), and controlling the rheological properties of the formulation obtainable therefrom. - Controlling mechanical properties, such as flexibility, scratch resistance, elasticity, ductility, flexural strength, tear resistance, resilience, hardness, density, resistance to tear propagation, compression set, performance at different temperatures, coefficient of thermal expansion, abrasion resistance, and other properties of solids or films containing silicone resin intermediates produced according to the method of the invention and composed of repeating units of formula (7) or organopolysiloxanes composed of repeating units of formula (8) and preparations thereof or preparations thereof, such as thermal conductivity, flammability, air permeability, water vapor resistance, hot air resistance, chemical resistance, weather resistance and radiation resistance, and sterilizability. - Controlling electrical properties, such as dielectric loss factor, dielectric strength, dielectric constant, resistance to tracking, resistance to arcing, surface resistivity, specific dielectric strength, flexibility, scratch resistance, elasticity, ductility, bending, tear resistance, resilience, hardness, density, resistance to tear propagation, compression set, and the properties of a solid or film that can be obtained from a silicone resin intermediate comprising repeating units of formula (7) or an organopolysiloxane comprising repeating units of formula (8) produced according to the method of the present invention and obtained from such formulations at different temperatures.

[0111] The present invention further provides silicone resin intermediates composed of repeating units of formula (7), block copolymer polyorganoalkoxysiloxanes composed of repeating units of formula (8), or formulations of the present invention for the following uses: production of artificial stone; or control of electrical conductivity and resistance; control of leveling properties of formulations; control of gloss of wet or cured films or products; increase weather resistance; increase chemical resistance; increase color stability; reduce chalking tendency; reduce or increase static friction and sliding friction; stabilize or destabilize foams; improve adhesion; control the wetting and dispersing properties of fillers and pigments; control rheological properties; control mechanical properties and other properties such as thermal conductivity, flammability, air permeability, water vapor resistance, hot air resistance, chemical resistance, weather resistance and radiation resistance, sterilizability, and electrical properties; control flexibility, scratch resistance, elasticity, ductility, flexural strength, tear resistance, resilience, hardness, density, tear propagation resistance, compression set, and performance at different temperatures; control transparency, heat resistance, yellowing tendency, and weather resistance.

[0112] Examples of applications in which the formulations of the present invention can manipulate the properties described above include the production of coating compositions and impregnating agents, as well as coatings and coverings that can be obtained from them on substrates such as metals; glass; wood; mineral substrates; synthetic and natural fibers for the production of textiles, carpets, floor coverings or other articles that can be produced from fibers; leather; and plastics such as films and moldings. With appropriate selection of formulation components, the silicone resin intermediates of the present invention consisting of repeating units of formula (7) or the organopolysiloxanes consisting of repeating units of formula (8) and formulations that can be obtained therefrom can also be used as additives in formulations for the following purposes: defoaming, flow promotion, hydrophobicity, hydrophilicity, filler and pigment dispersion, filler and pigment wetting, substrate wetting, promoting surface smoothness, and reducing adhesion and sliding resistance on the surface of the cured compound from which the additive formulation is available. Silicone resin intermediates consisting of repeating units of formula (7) or organopolysiloxanes consisting of repeating units of formula (8) and formulations that can be obtained therefrom, produced according to the method of the present invention, can be incorporated into elastomeric compounds in liquid or cured solid form. They can be used here to enhance or improve other performance characteristics, such as controlling transparency, heat resistance, yellowing tendency, and weather resistance.

[0113] The present invention further provides the use of silicone resin intermediates consisting of repeating units of formula (7), block copolymer polyorganoalkoxysiloxanes consisting of repeating units of formula (8), or formulations of the present invention for the production of coating compositions and impregnating agents, as well as coatings and coverings that can be obtained therefrom on substrates such as metals; glass; wood; mineral substrates; synthetic and natural fibers for the production of textiles, carpets, floor coverings or other articles that can be produced from fibers; leather; plastics such as films and moldings.

[0114] All the symbols mentioned above in the above formulas are defined independently of each other in each case. In all formulas, the silicon atom is tetravalent.

[0115] Embodiments: The method of the invention is described in the following examples, but the invention is not limited to the examples and the contents disclosed therein. All percentages are by weight. Unless otherwise stated, all operations were performed at room temperature of about 23°C and at standard pressure (1.013 bar). The instruments are commercially available laboratory equipment, such as those commercially supplied by multiple equipment manufacturers.

[0116] Ph represents the phenyl group = C6H5-

[0117] Me represents a methyl group = CH3-. Therefore, Me2 represents two methyl groups.

[0118] In this paper, substances are characterized by reporting data obtained through instrumental analysis. The measurements upon which they are based are performed according to publicly available standards or determined through specially developed processes. To ensure clarity of the given instruction, the methods used herein are specified as follows: Viscosity: Unless otherwise specified, viscosity is determined by rotational viscosity determination according to DIN EN ISO 3219. Unless otherwise specified, all viscosity data refer to a standard pressure of 25°C and 1013 mbar.

[0119] Molecular composition: Molecular composition is determined by nuclear magnetic resonance spectroscopy (for terminology, see ASTM E 386: High-Resolution Nuclear Magnetic Resonance (NMR) Spectroscopy: Terminology and Symbols), in which the measurement 1 H nucleus and 29 Si core.

[0120] Description of 1H-NMR measurements

[0121] Solvent: CDCl3, 99.8% D

[0122] Sample concentration: approximately 50 mg / 1 ml CDCl3 in a 5 mm NMR tube.

[0123] Measurements without the addition of TMS were referenced to the spectrum of residual CHCl3 in CDCl3 at 7.24 ppm.

[0124] Spectrometer: Bruker Avance I 500 or Bruker Avance HD 500

[0125] Probe: 5 mm BBO probe or SMART probe (Bruker)

[0126] Measurement parameters: Pulprog = zg30 TD = 64k NS = 64 or 128 (depending on probe sensitivity) SW = 20.6 ppm AQ = 3.17 s D1 = 5 s SFO1 = 500.13 MHz O1 = 6.175 ppm Processing parameters: SI = 32k WDW = EM LB = 0.3 Hz Depending on the type of spectrometer used, individual adjustments to the measurement parameters may be required.

[0127] 29 Description of Si NMR measurements

[0128] Solvent: C6D6 99.8% D / CCl4 1:1 v / v, containing 1% by weight Cr(acac)3 as a relaxation agent.

[0129] Sample concentration: approximately 2 g / 1.5 ml solvent in a 10 mm NMR tube.

[0130] Spectrometer: Bruker Avance 300

[0131] Probe: 10 mm 1H / 13C / 15N / 29Si glassless QNP probe (Bruker)

[0132] Measurement parameters: Pulprog = zgig60 TD = 64k NS = 1024 (depending on probe sensitivity) SW = 200 ppm AQ = 2.75 s D1 = 4 s SFO1 = 300.13 MHz O1 = -50 ppm Processing parameters: SI = 64k WDW = EM LB = 0.3 Hz Depending on the type of spectrometer used, individual adjustments to the measurement parameters may be required.

[0133] HCl content

[0134] The HCl content was determined by directly titrating the isopropanol sample solution with ethanol-potassium hydroxide solution against tetrabromophenolphthalein ethyl ester.

[0135] Molecular weight distribution: Molecular weight distribution was determined as weight-average Mw and number-average Mn using gel permeation chromatography (GPC) and size exclusion chromatography (SEC) with polystyrene standards and a refractive index detector (RI detector). Unless otherwise specified, THF was used as the eluent, following DIN 55672-1. Polydispersity was expressed as the ratio Mw / Mn.

[0136] Example 1: Block copolymer organopolysiloxane resin was produced using a reaction tower and a loop with short-path distillation, wherein polydimethylsiloxane was supplied to the bottom of the tower.

[0137] Methyltrichlorosilane was continuously supplied at a rate of 1500 g / h to the upper third of the reaction column. There, it reacted countercurrently with ethanol from below to form methyltriethoxysilane. The released HCl was discharged to the exhaust system through a reflux condenser at the top of the column, and the resulting condensate was continuously returned to the upper third of the column. The alkoxylate fell to the bottom of the column, where 170 g / h of water, 1370 g / h of ethanol, and 150 g / h of α,0-dihydroxypolydimethylsiloxane with a viscosity of 70 mPa·s were continuously added. The reaction mixture was collected from the bottom of the column in a sample container while maintaining a constant fill level at the bottom. A clear solution of the partial condensate in ethanol with an HCl content of 35 ppm was obtained. The ethanol content was determined to be 29% by weight by 1H NMR. 29Si NMR showed that the partial condensate contained 1 mol% methyltrimethoxysilane and 34 mol% MeSi(OEt)₂O. 1 / 2 38 mol% MeSi(OEt)O 2 / 2 10 mol%MeSiO 3 / 2 1 mol% Me2Si(OEt)O 1 / 2 and 16 mol% Me2SiO 2 / 2 The average composition.

[0138] A partial condensate solution of 3000 g / h was continuously metered with 120 g / h of water and 13.8 g / h of 20% hydrochloric acid (by weight) in a turbulent loop with a volume of 1.5 L, while maintaining a temperature of 70°C. The overflow reaction mixture was devolatiled to 0.6% ethanol and 12 ppm HCl by weight in a short-path distillation at standard pressure using a heating index of 140°C. A turbid liquid with a viscosity of 430 mPa·s was obtained. 29Si NMR indicated a 1 mol% MeSi(OEt)₂O₃ content. 1 / 2 32 mol% MeSi(OEt)O 2 / 2 50 mol% MeSiO 3 / 2 1 mol% Me2Si(OEt)O 1 / 2 and 16 mol% Me2SiO 2 / 2 The average composition.

[0139] Example 2: Block copolymer organopolysiloxane resin was produced using a pre-reactor, a reaction tower, and a batch reactor with a reflux condenser and a distillate distributor, wherein polydimethylsiloxane was supplied to the bottom of the tower.

[0140] A continuous supply of 40 kg / h of methyltrichlorosilane is provided to the pre-reactor upstream of the reaction tower. A 15 kg / h supply of ethanol / HCl condensate from the stirrer unit distillation is also provided to the pre-reactor, causing partial alkoxylation of the methyltrichlorosilane. The HCl released during this process is discharged as gas from the pre-reactor via a reflux condenser to the exhaust system.

[0141] The reaction mixture containing partially alkoxylated methyltrichlorosilane was continuously transferred from the pre-reactor to the upper third of the reaction column. There, it reacted countercurrently with ethanol from below to form methyltrimethoxysilane. Residual HCl was discharged into the exhaust system via a reflux condenser from the top of the column, and the resulting condensate was continuously returned to the upper third of the column. The alkoxylated compound settled at the bottom of the column, where 5.7 kg / h of water, 30 kg / h of ethanol, and 5.0 kg / h of α,0-dihydroxypolydimethylsiloxane with a viscosity of 70 mPa·s were continuously added. The reaction mixture was collected from the bottom of the column in a sample container while maintaining a constant fill level at the bottom. A clear solution of the partial condensate in ethanol with a HCl content of 50 ppm was obtained. The ethanol content was determined to be 28% by weight by 1H NMR. 29Si NMR indicated that the partial condensate contained 1 mol% methyltrimethoxysilane and 33 mol% MeSi(OEt)₂O. 1 / 2 39 mol% MeSi(OEt)O 2 / 210 mol% MeSiO 3 / 2 1 mol% Me2Si(OEt)O 1 / 2 and 16 mol% Me2SiO 2 / 2 The average composition.

[0142] In a stirrer unit, 306 kg of a partially condensed product solution, 17.8 kg of water, and 1.38 kg of 20% hydrochloric acid (by weight) were stirred for 30 minutes at 70°C and standard pressure. The solution was then devolatiled until a bottom temperature of 100°C and an absolute pressure of 100 mbar were reached, resulting in an ethanol content of 0.3% by weight and an HCl content of 4 ppm by weight. A turbid liquid with a viscosity of 650 mPa·s was obtained. 29Si NMR analysis indicated an average composition of 0.5 mol% MeSi(OEt)₂O. 1 / 2 31.5 mol% MeSi(OEt)O 2 / 2 51 mol.-% MeSiO 3 / 2 1 mol% Me2Si(OEt)O 1 / 2 and 16 mol% Me2SiO 2 / 2 .

[0143] Comparative Example 1: Block copolymer organopolysiloxane resin was produced using a reaction tower, wherein polydimethylsiloxane was supplied to the upper third of the tower.

[0144] 1500 g / h of methyltrichlorosilane and 150 g / h of α,o-dihydroxypolydimethylsiloxane with a viscosity of 70 mPa·s were continuously supplied to the upper third of the reaction column. There, methyltrichlorosilane reacted countercurrently with ethanol from below to form methyltriethoxysilane. The released HCl was discharged to the exhaust system via a reflux condenser through the top of the column, and the resulting condensate was continuously returned to the upper third of the column. In the lower two-thirds of the column, gradual deposition of gel particles occurred, meaning continuous operation was not possible. The alkoxylated-siloxane mixture fell to the bottom of the column, where 170 g / h of water and 1370 g / h of ethanol were continuously added. The reaction mixture was collected from the bottom of the column in a sample container while maintaining a constant fill level at the bottom. A turbid liquid was obtained, which separated into two phases after 24 hours, and therefore no further analysis was performed.

[0145] Comparative Example 2: Block copolymer organopolysiloxane resin was produced using a reaction tower and a loop with short-path distillation, wherein polydimethylsiloxane was supplied to the loop.

[0146] Methyltrichlorosilane was continuously supplied at a rate of 1500 g / h to the upper third of the reaction column. There, it reacted countercurrently with ethanol from below to form methyltriethoxysilane. The released HCl was discharged through a reflux condenser to the exhaust system via the top of the column, and the resulting condensate was continuously returned to the upper third of the column. The alkoxy compound fell to the bottom of the column, where 170 g / h of water and 1370 g / h of ethanol were continuously added. The reaction mixture was collected from the bottom of the column in a sample container while maintaining a constant fill level at the bottom. A clear solution of the partial condensate in ethanol with a HCl content of 30 ppm was obtained. The ethanol content was determined to be 49% by weight by 1H NMR. 29Si NMR showed that the partial condensate contained 0.2 mol% methyltrimethoxysilane and 19 mol% MeSi(OEt)₂O. 1 / 2 58 mol% MeSi(OEt)O 2 / 2 and 22.8 mol% MeSiO 3 / 2 The average composition.

[0147] A partial condensate solution of 2850 g / h was continuously metered into a 1.5 L loop tube with turbulent flow, along with 150 g / h of α,0-dihydroxypolydimethylsiloxane (viscosity 70 mPa·s), 120 g / h of water, and 13.8 g / h of 20% hydrochloric acid (by weight), and maintained at 70°C. The overflow reaction mixture was devolatiled to less than 30 ppm HCl by short-path distillation at standard pressure using heating at 140°C. A turbid liquid was obtained, which separated into two phases after 24 hours; therefore, no further analysis was performed.

[0148] The results show that, according to this method, at least in the absence of a solvent (i.e., in the absence of a solvent that does not correspond to the alcohol used for the alkoxylation reaction), it is impossible to add polydimethylsiloxane at a freely chosen point, because gel formation and two-phase formation would cancel this out.

Claims

1. A method for the continuous production of block copolymer polyorganoalkoxysiloxanes, comprising the following steps in the order stated: (i) Reacting at least one chlorosilane with an alcohol or a mixture of alcohols in a pre-reactor to form a reaction mixture containing a partial alkoxylate, (ii) The reaction mixture obtained after step (i) is transferred to a first reaction unit, which is connected to the pre-reactor and includes a tower having an upper end, a lower end, and a feed point. The transfer is achieved by transferring the reaction mixture to the tower via the feed point. The feed point of the column is configured such that the reaction mixture is fed into the middle third of the column's total length. (iii) The reaction mixture transferred to the tower in step (ii) is conveyed within the tower, which proceeds downwards under gravity. The partial alkoxylate is combined with another alcohol or a mixture of other alcohols, wherein the partial alkoxylate reacts to form a complete alkoxylate before the reaction mixture reaches the bottom of the column, the distance between the bottom of the column and the bottom end of the column does not exceed 25% of the total length, and the complete alkoxylate is subsequently present at the bottom of the column. (iv) The fully alkoxylated compound in the lower part of the column of the first reaction unit is reacted with another alcohol or a mixture of other alcohols, water, and at least one silanol-terminated polydiorganosiloxane to form a low-condensation polyorganosiloxane mixture (crude mixture). (v) The crude mixture obtained after step (iv) is transferred to a second reaction unit, which is connected to the first reaction unit and includes an additional continuous reactor, thereby realizing the transfer to the additional continuous reactor, and (vi) The crude mixture transferred in step (v) is reacted with another alcohol or a mixture of other alcohols and with water to form a polyorganosiloxane mixture having a higher degree of condensation than the crude mixture.

2. The method according to claim 1, wherein, For step (iv), the silanol-terminated polydiorganosiloxane is metered into the bottom of the first reaction unit.

3. The method according to claim 1 or 2, wherein, The continuous reactor within the second reaction unit is designed as a loop reactor.

4. The method according to any one of the preceding claims, wherein no other organic components, preferably no other low molecular weight components, and in particular no inert organic solvents are used throughout the method except for the alcohol required for the reaction.

5. The method according to any one of the preceding claims, wherein, In method steps (i), (iii), (iv) and (vi), only one specific alcohol is used for the reaction in each case, preferably the same alcohol.

6. The method according to any one of the preceding claims, wherein, The chlorosilane corresponds to the following general formula (1): R n SiCl 4-n (1), in, R represents a hydrogen group or an acid-stabilized C1-C18 hydrocarbon group optionally substituted with at least one heteroatom, and n can have values ​​of 0, 1, 2, or 3.

7. The method according to any one of the preceding claims, wherein, The produced block copolymer polyorganoalkoxysiloxane contains linear D units (R 1 2SiO 2 / 2 ) and nonlinear crosslinked T units (R 2 SiO 3 / 2 ), The D units are primarily linked together in the form of oligomeric or polymeric chains, each chain having a length of at least four D units in a direct and uninterrupted sequence, and / or In this configuration, the nonlinear T-units form a block consisting of at least four T-units in an uninterrupted sequence, wherein the nonlinear blocks can further interlink with each other. Among them, R 1 and R 2 Each is independent as defined for R.

8. The method according to claim 7, wherein, The block copolymer polyorganoalkoxysiloxane further comprises units of general formula (3) in the nonlinear blocks composed of T units: R 2 c R 3 d SiO (4-c-d) / 2 (3), in R 2 It is as defined for R. R 3 This represents a condensable group in the form of -OR, where R is as defined above, and c represents the number 1, and c + d can take the values ​​1, 2 or 3, where d represents the value 0, 1 or 2.

9. The method according to any one of the preceding claims, wherein, The silanol-terminated polydiorganosiloxane corresponds to the following general formula (4): HO-(R 2 2SiO 2 / 2 ) e -OH (4), Among them, R 2 Represents group R, and e represents an integer from 4 to 2000.

10. The method according to any one of the preceding claims, wherein, Additional alkoxy and / or hydroxyl-functionalized organopolysiloxanes and / or alkoxy and / or hydroxyl-functionalized silanes are added in metered amounts to the second reaction unit. Additional alkoxy and / or hydroxyl functionalized organopolysiloxanes are those composed of repeating units of general formula (5), and additional alkoxy and / or hydroxyl functionalized silanes are those composed of repeating units of general formula (6): R p Si(OR 4 ) q O (4-p-q) / 2 (5), In the unit of equation (5) R is as defined above. R 4 Indicates the same or different monovalent C1-C6 alkyl groups or hydrogens. In the unit of equation (5), p and q can have values ​​of 0, 1, 2, or 3, provided that... p + q ≤ 3, and In at least 20% of all repeating units in equation (5), p has a value of 1; R 5 o Si(OR 4 ) 4-o (6), in R 5 It is a hydrocarbon group that does not contain any nitrogen atoms. R 4 It is as defined above, and o represents a number with a value of 0, 1, 2, or 3.

11. A silicone resin intermediate, which is obtainable after step (iv) of the method according to any one of the preceding claims, said silicone resin intermediate being formed from repeating units of the following general formula (7): R 6 x Si(OR 7 ) y O (4-x-y) / 2 (7), in, In the unit of equation (7) R 6 Represents group R, Among them, R 7 For R 4 Defined In equation (7), x represents the value 1 or 2, and In the unit of equation (7), y can have the values ​​0, 1, 2, or 3, provided that... x + y ≤ 4, and x has a value of 1 in at least 30% of all repeating units in equation (7) and a value of 2 in at least 5% of them. Among them, the repeating unit of equation (7) with x having a value of 2 can have at most one equation OR. 7 The group, such that in these repeating units, y = 0 or 1, the repeating units are further linked together to form a segment of at least four repeating units in an uninterrupted sequence. In the silicone resin intermediate composed of repeating units of formula (7), unit OR 7 This indicates a maximum of 10% hydroxyl groups by weight.

12. A block copolymer polyorganoalkoxysiloxane obtainable by the method of any one of claims 1-10, said polyorganoalkoxysiloxane being formed from repeating units of general formula (8): R 6 f Si(OR 7 ) g O (4-f-g) / 2 (8) in, In the unit of equation (8) R 6 and R 7 As defined above, In the unit of equation (8), f and g can have values ​​of 0, 1, 2, or 3, provided that f + g ≤ 3, and f has a value of 1 in at least 30% of all repeating units in equation (7) and a value of 2 in at least 5% of them. The repeating units are further connected together to form a chain segment of at least four repeating units in an uninterrupted sequence. The average value of g across all repeating units in general formula (8) ranges from 0.05 to 1.

7. In the organopolysiloxane composed of repeating units of formula (8), the unit OR 7 This indicates a maximum of 10% hydroxyl groups by weight.

13. A formulation comprising at least one silicone resin intermediate of claim 11 and / or at least one block copolymer polyorganoalkoxysiloxane of claim 12, and at least one auxiliary agent.

14. The silicone resin intermediate of claim 11, the block copolymer polyorganoalkoxysiloxane of claim 12, or the formulation of claim 13 are used for: corrosion protection; production of artificial stone; or control of electrical conductivity and resistance; control of the leveling properties of the formulation; control of the gloss of the wet or cured film or product; increase weather resistance; increase chemical resistance; increase color stability; reduce chalking tendency; reduce or increase static and sliding friction; stabilize or destabilize foam; improve adhesion; control the wetting and dispersing properties of fillers and pigments; control rheological properties; control mechanical properties and other properties such as thermal conductivity, flammability, air permeability, water vapor resistance, hot air resistance, chemical resistance, weather resistance, radiation resistance, sterilizability, and electrical properties; control flexibility, scratch resistance, elasticity, ductility, flexural strength, tear resistance, resilience, hardness, density, tear propagation resistance, compression set, and performance at different temperatures; control transparency, heat resistance, yellowing tendency, and weather resistance, especially corrosion protection.

15. The silicone resin intermediate of claim 11, the block copolymer polyorganoalkoxysiloxane of claim 12, or the formulation of claim 13 is used for the production of coating compositions and impregnating agents, and coatings and coverings that can be obtained therefrom on substrates such as metals; glass; wood; mineral substrates; synthetic and natural fibers used in the production of textiles, carpets, floor coverings, or other articles that can be produced from fibers; leather; and plastics such as films and moldings.