JPS6164731A - Production of solution of organosilicon compound in polar organic solvent - Google Patents

Abstract

PURPOSE:To produce the titled stable solution in good efficiency, by treating a solution comprising a water-soluble alkali salt of a polysiloxane, an alcohol and water at a specified composition with an ion exchanger, adjusting the pH and distilling the water. CONSTITUTION:A solution comprising 5-20wt% water-soluble alkali salt of a polysiloxane of formula I (wherein R is a 1-4C alkyl, 2-4C alkenyl or phenyl), 30-90wt% alcohol of formula II (wherein R' is a 1-4C alkyl) and 5-60wt% water is treated with a weakly acidic cation exchange resin to remove alkali from said salt and form the polysiloxane. The pH of the obtained solution is adjusted to 3-6.8, and a desired polar organic solvent (which may be the same alcohol as the one used above) is added thereto. A solution of the polysiloxane in a polar is obtained by completely distilling off at least the water contained therein by heating.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing a solution of an organosilicon compound in a polar organic solvent.

[Conventional technology]

Generally, polysiloxanes represented by R''sio (R' is a monovalent organic group) are infusible and insoluble solids, and no particularly effective use has been found for them as they are. It is well known that when such polysiloxane reacts with an alkali, it forms an alkali salt of silanol, resulting in a water-soluble compound.

The water-soluble alkali salt of the polysiloxane is ion-exchanged to remove the alkali component, and then stabilized as necessary.
In particular, a method for obtaining an Iζζ liquid using water or an organic solvent as a dispersing agent by stabilizing it by adding a basic component is already known (JP-A-53-86897 and JP-A-54-5
0557 publications).

When removing alkaline components in this method, the concentration of water-soluble alkali salt of polysiloxane in a solution mainly using water as a solvent to be subjected to ion exchange is carried out at several percent. If the concentration of alkali salt in the solution to be subjected to ion exchange is low, it is necessary to remove the solvent after ion exchange to increase the concentration of polysiloxane. Especially when water is mainly used as the solvent, a large amount of energy,
It requires a long time, and the thinner the concentration, the more labor it takes.

Therefore, it is possible to increase the concentration of the alkali salt, but simply increasing the concentration of the alkali salt will cause the condensation of 7-ranol in the polysiloxane to proceed during ion exchange.
There is a problem in that the polysiloxane becomes an infusible and insoluble solid (hereinafter referred to as gelation), making it impossible to obtain a polysiloxane that is soluble in the target colloid liquid or organic solvent.

The present inventors investigated a method that improves the drawbacks of the prior art and enables ion exchange in a solution state containing a highly concentrated active ingredient. As a result, the present inventors found that by selecting a specific solution composition, a highly concentrated active ingredient can be exchanged. Poly'/Q can undergo ion exchange while still containing it, is stable without adding basic components such as alkali metal salts, and is soluble in various polar organic solvents.
We found that chitin can be obtained and have already proposed it.

[Problem that the invention seeks to solve]

Although the polysiloxane solution obtained by the above method using water and alcohol as a solvent can be used as it is for certain applications, other applications include alcohol only,
Alternatively, there are also applications where it is desired to use it as a solution of various polar organic solvents.

Generally, in order to dehydrate a water-containing solution or replace it with another solvent, you can add the desired solvent or distill off the solvent forming the original solution under heating without adding the desired solvent. is achieved.

However, polysiloxane having R'5iOy as a basic structural unit gels when heated and becomes insoluble in ordinary organic solvents again, making it impossible to obtain the desired solution.

Therefore, the present inventors solved the above problem and developed a method for removing water from the solution obtained by the above-mentioned ion exchange operation in a stable state. The present invention was achieved as a result of extensive research aimed at obtaining a polar organic solvent solution of an organosilicon compound by substituting alcohol or a polar solvent other than alcohol.

[Means for solving problems]

The above objects of the present invention are as follows: (a) A water-soluble alkali salt of a polysiloxane represented by the general formula R3103 (R is C+-4c') ayayaya, 02-4 alkenyl, phenyl), a water-soluble alkali salt of a polysiloxane of the general formula R'OH;
A solution containing an alcohol represented by (R't&C, ~4 alkyl) and water, in which the water-soluble alkali salt of polysiloxane in the solution is 5 to 20% by weight, and the R'OH group is 30-9'O (b) The solution obtained by ion exchange is adjusted to pH 3,
(C) Adding alcohol or other polar organic solvent contained in the solution to the pH-adjusted solution; and (d) Adding the polar organic solvent-containing solution to the pH-adjusted solution. This can be achieved by employing a method for producing a solution of an organosilicon compound in a polar organic solvent, which comprises heating the solvent to distill off a solvent containing at least water.

The present invention will be further explained in detail below.

The alkyl group of the polysiloxane moiety of the water-soluble alkali salt of boriaoxane represented by the general formula RS IOx used in the present invention is Cl~, for example, methyl,
Ethyl, propyl, etc. or C2-4 alkenyl, such as vinyl, α-methylvinyl, β-methylvinyl,
Allyl, etc., or phenyl, and polysiloxanes containing two or more of these organic groups can also be used. Preferred organic groups are methyl, ethyl, vinyl, phenyl and the like.

The alkaline part of the water-soluble alkali salt of Boria 0 xane is L
It is one type or a mixture of two or more types of alkali metals returned from i, Na, and K. Preferably the alkali metal is Na or K. In order to form a water-soluble alkali salt, the alkali metal must contain 0.3 to 3.0 equivalents per equivalent of silicon in the polysiloxane, particularly preferably 0.5 to 2 to 0 equivalents. It is.

These water-soluble alkali salts of polysiloxane are R31
X3 (R is the above-mentioned organic group, halogen, alkoxy,
A polysiloxane represented by RS iOy is obtained by hydrolyzing seven runs represented by (a/roxy, oximo) and reacting with an aqueous alkali solution, or by a method of directly reacting R5i x with an aqueous alkali solution. R5
As 1X3, methyltrichlorsila/, methyltribromosilane, methyltrimethoquino7rane, methyltris(methoxynoethoxy)/:7rane, methyltrimethoquino7rane, methyltris(methylethylketooxomosila/), ethyltrichlorrunan, Ethyltriethoxy/7ran, vinyltrichlor/U/, vinyltrimethoxy7/, vinyltriacetkinsila/, allyltrichlorsila/, allyltrimethquinoneran, 7enyltrichlor 7ran, phenyltriethoxy7/rano, etc. be able to.

Hydrolysis of these silanes in the presence of water yields polysiloxanes represented by R31o which are insoluble in water and common organic solvents.

The alkaline aqueous solution includes Li, Na, K oxides, hydroxides, carbonates, hydrogen carbonates, hydrogen sulfates,
It is an aqueous solution of a compound that shows alkalinity in an aqueous solution such as a hydrogen salt or an acid hydrogen salt, and a solution containing a water-soluble organic solvent such as an alcohol, a carboxylic acid, a ketone, or a nitrile in the aqueous solution can also be used. Those containing lower alcohols are preferably used. This special program is preferably used;'s 7 lfi'l aqueous solution +t NaO[(,N
aHCO, an aqueous solution of Na2CO2 or a mixed solution of water and methanol.

The concentration of the alkaline component can be used within a wide range, but is preferably 1 to 50%, particularly preferably 5 to 40%. Is the aqueous alkaline solution d? Silicon 1 in Phosphoroxano
It is preferable to use the alkali metal in an amount of 0.3 equivalent or more, preferably 0.5 to 2.0 equivalent. The reaction of polysiloxane with an alkaline aqueous solution is as follows:
It is carried out by heating and stirring both.There is no particular restriction on humidity, and the higher the temperature, the shorter the reaction time.
In order to heat the solvent above the boiling point, pressure is required, so it is usually preferable to carry out the heating near the reflux temperature of the solvent.
The reaction time depends on the type of polynoloxane 9, the type of alkali,
Although it depends on the concentration, temperature, and solvent system, it usually takes several tens of minutes to several hours.

In the method of directly reacting R51X with an alkaline aqueous solution, if R51Xx is hydrolyzed to produce hydrohalic acid or carboxylic acid, such as trihalogenosilane or trisiloxylane, these acids are It is necessary to add an extra amount of alkaline component necessary for compatibility.

In the present invention, the composition of the solution used for ion exchange is controlled within a specific range. It is necessary to maintain That is, at least a water-soluble alkali salt of polysiloxane, l'j'
A solution containing alcohol represented by OH (R' is C14 alkyl) and water, containing 5 to 20% by weight of a water-soluble alkali salt of polysiloxane based on the total weight of the solution.
, R' 01 (3θ~90% by weight, water 5~60% by weight
fi% range, preferably 8 to +8.50 in the order of
The composition should be in the range of ~80, IO ~30 Bm.

A solution containing a water-soluble alkali salt of a polysiloxane having the above composition is prepared by adding an alcohol represented by R'OH after concentrating an aqueous solution of an alkali salt of a polysiloxane obtained by reacting a polysiloxane with an aqueous alkali solution, if necessary. to obtain the desired composition, or add polysiloxane to alkaline water-R.
It can be obtained by reacting with a mixed solution of 'OH, and if necessary, concentrating, adding R'OH, etc. to obtain a desired composition.

Alcohol and Shiteha represented by R'OH used for
Methyl alcohol, ethyl alcohol, n-globyl alcohol and its isomers, n-butanol and its isomers, and mixtures thereof may be used. Particularly preferred alcohols are methyl alcohol and ethyl alcohol. .

If the composition of the solution used for ion exchange is outside the above range, it may not be possible to form a uniform solution, gelation of polysiloxane may progress during ion exchange, or gelation may occur after ion exchange unless a basic component is added. As a result, the desired polysiloxane soluble in polar organic solvents cannot be obtained.

For example, if the water-soluble alkali salt of polysiloxane exceeds 20% by weight, it will gel during ion exchange, and if the alcohol represented by R'OH is less than 30% by weight, it will gel during ion exchange, or the basic component will be removed after ion exchange. If not added, gelation will proceed.

As long as the water-soluble alkali salt of polysiloxane and R'OH1 water in the solution used for ion exchange is within the above-mentioned range, it may contain other paid compounds and inorganic salts that form a uniform solution.

For example, when obtaining a water-soluble alkali salt of polysiloxane, alkali metal salts of hydrohalokenates, carboxylic acid salts, alcohols, oximes, etc. derived from R51X, a water-soluble organic solvent contained in an alkaline aqueous solution, are also included.
There is no need to remove it as long as it does not deviate from the above composition range.

In removing alkaline components from such solutions by ion exchange, ion exchange resins, ion exchange fibers, ion exchange membranes, etc. can be used as long as they have the ability to exchange ions with alkaline components.

Usually, it is preferable to use a sulfonic acid type or carboxylic acid type cation exchange resin of strong acidity or weak acidity.

When using an ion exchange resin, there is a batch method in which the ion exchange resin is brought into contact with a solution containing a water-soluble alkali salt of Boria Ogosan at once and then separated, or the ion exchange resin is packed in a tower-like structure. This can be carried out by a flow-down method in which the water-soluble alkali salt of polysiloxane is allowed to flow down, but from an industrial perspective, the flow-down method is preferably employed, including the regeneration of the ion exchange resin. In the case of the flow-down method, the solution supply rate, that is, Sv, can be set at a wide range, and is 0.1
- Possible in 10.0 hrl, preferably 0.5 to 6
．． It is best to use 0hrl.

If the temperature during ion exchange is too high, gelation will proceed during ion exchange, so a lower temperature is preferable, and it is usually best to carry out the temperature around room temperature.

After removing the alkali component, it is a preferable form to further perform ion exchange of anions in order to remove the anions contained as necessary.

Particularly when trihalogenosilane is used as a starting material, it is preferable to treat the solution with an anion exchange resin in order to remove halogen ions contained in the solution.

In the present invention, the pH of the thus obtained polysiloxane solution, which is substantially free of alkali components and whose solvent is mainly water and alcohol, is adjusted to 3.0 to 6.8, preferably 4.0 to 6.5. It is important to retain. This is to prevent polysiloxane from gelling.

After performing cation exchange to remove alkaline components in ion exchange, if anion exchange is performed to further remove contained anions, the pH will exceed 6.8.
Since a neutral solution around 7 is obtained, the pH is adjusted to the above pH range.

The method for maintaining the pH at 3.0 to a8. is based on known means. Preferably, various acidic compounds such as inorganic protic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, aluminum chloride,
Compounds that generate acids by reacting with Lewis acids such as titanium chloride, 37-nocaboron, tetrachlorosilane/methyltrichlorosilane, water or alcohol, carboxylic acids such as acetic acid, propionic acid, and benzoic acid, methanesulfonic acid, A method is adopted in which a sulfonic acid such as he/ze/sulfonic acid or toluefsulfonic acid is added to the polysiloxane solution.

The acidic polysiloxa/solution thus obtained is
Depending on the application, inorganic ionic compounds may be disliked, but in such cases it is preferable to use a lower carboxylic acid such as acetic acid or propionic acid as the carboxylic acid.

Due to the acidic compounds contained in the solution subjected to ion exchange, if only cation exchange is performed, the resulting pH will be 3.0.
A solution of ~6.8 may be obtained. In this case, there is no need to adjust the pH again, and it is a preferable method if the ionic compounds contained therein do not need to be removed. Also, depending on the amount and type of acidic compounds contained in the solution to be subjected to ion exchange, a pf (of less than 3.0 can be obtained. In this case, by adding a basic compound, the pH can be lowered to 3. Although it is possible to adjust the value to 0 to 6.8, this is not a preferable method because it requires the addition of another ionic compound.

In the present invention, the above-mentioned pH-adjusted borine akit
/ Alcohol or other polar organic solvent is added to the solution, and the solvent containing at least water is distilled off while heating. As a result, a solution containing substantially only alcohol or a solution containing a polar organic solvent can be obtained.

The composition of the solvent distilled out under heating is highly dependent on the boiling point of the polar organic solvent added.

For example, when the ion exchange solution is a mixed solvent of water and methanol, what is distilled out by adding and heating methanol is
It is a water-methanol mixture whose main component is methanol. Therefore, in order to obtain a solution containing substantially only methanol, it is necessary to add methanol and perform distillation under heating many times.

On the other hand, when using something with a higher boiling point than water or methanol, such as cyclohexanol, the distillate is water,
Since methanol is the main component, a solution of substantially cyclohexanol can be easily prepared.

The addition of the polar organic solvent and the distillation of the solvent containing at least water by heating may be carried out by alternating addition, distillation, and addition, or by continuous heating and distillation while adding the polar organic solvent. It could even be a law.

When performing alternately, some of the ion exchange solution is distilled off first,
There is no problem in adding a polar organic solvent next.

Since heating is performed to distill off the solvent containing at least water, it is necessary to boil the content liquid. It can be selected arbitrarily by adjusting temperature and pressure. Usually 30℃ to 200℃, preferably 50-15
0°C, 0.01xxHy to normal pressure, preferably l WH
It is carried out in the range from j to normal pressure.

In addition, if the acid used to adjust the pH of the ion exchange solution is volatile, the addition of a polar organic solvent and distillation by heating may reduce the a-fluorescence in the system and increase the pf. Ability to add additional acid or add polar solvent to which acid is added during operation; preferred.

The polar organic solvent here refers to intramolecular alcohol,
Ether, ketone, carboxylic acid, ester, amide, nitrile, amine, oxime, nide a, sulfoxide 1.
It is an organic compound that has a polar group such as sulfone and is liquid at around room temperature.

Hydroxy ethers, hydroxy ketones, keto ethers, hydroxy carboxylic acids, hydroxy esters, keto esters, amino alcohols, nitro alcohols, nitro esters, etc. having a plurality of polar groups in one molecule can also be preferably used.

Specific compounds include methanol, ethanol, clopanol, butanol, cyclohexanol, β-chloroethanol, ethylene glycol, propylene glycol, diethyl ether, dipropyl ether,
Tetrahydrofuran, anisole, dimethoxy7-ethane, Shedkin ethane, dioxane, ethoxyethanol, butoxyethanol, ethoxyethoxyethanol,
Acetone, methyl ethyl ketone, methyl ibutyl ketone, cyclohekitenone, acetophenone, ingropylidene acetone, acetone alcohol, diacetone alcohol, acetic acid, propionic acid, α-chloropropionoic acid,
Acrylic acid, methacrylic acid, acetoacetic acid, methyl acetate,
Ethyl acetate, butyl acetate, cyclohexyl acetate, methyl glopionate, methyl a or β-chlorpionate, methyl acrylate, methyl methacrylate, methyl acetoacetate, ethylene glycol monoacetate, ethylene glycol monoacetate, ethylene Glycolone acrylate, ethylene glycol monoacrylate, ethylene glycol monomethacrylate, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, N-methyl-ε-caprolactam, N-vinylpyrrolidone, acetonitrile, gropionitrile, acrylonitrile, triethylamine, pyridine, Aniline,
Dimethylaniline, ethanolamine/, methyl ethyl ketoxime, nitrobenzene, dimethyl sulfoxide,
Examples include sulfolane, and mixtures of two or more thereof.

The solution of polysiloxane in a polar organic solvent obtained in this way can be applied to the surface of plastic, glass, metal, etc., dried, and cured to make it water repellent, weather resistant, etc.
It can be effectively used to impart heat resistance, electrical insulation, etc., or to improve heat resistance and electrical properties by mixing and molding with plastics.

The effects of the present invention will be further explained below with reference to Examples, but these are not intended to limit the present invention in any way.

〔Example〕

Example 1 iVIesicl 3 1 # was reacted with 10g of water, and the resulting solid MeSiOH was separated from P, washed with water, and dried to obtain 380f.

MeSiOx 3001 and 30% Na0f (aqueous solution 60
0f was reacted at 90℃ for 4 hours, and some of the remaining solid was converted to P.
Separately, it was washed with water and the washing liquid was combined to obtain a transparent liquid 1250F. This solution contains 32.4% alkali salt of Me S io 7, and the atomic ratio of Si and Na is 1ull.
Met. In addition, 350F of CI roots were included.

Water was distilled off from this solution under reduced pressure, and MeSiOs
,; was concentrated so that the alkali salt concentration was 50%.

This product 809 and MeOH were mixed in L87f to obtain an ion exchange liquid. Alkaline salt of MeSiOy at this time:
The MeOH:water ratio is 0:15 near 15. Strongly acidic cation exchange resin strained in acid form in a glass tube of 30mmφ x 500mm with a cock (Mitsubishi Kasei: SK IB)
22 to fill 300ml and roughly remove C1 roots.
A fl.phi.

MeSi07 Arca that I prepared earlier! J.W., MeO.
H.

A solution consisting of water was passed through a strongly acidic cation exchange resin and then a weakly basic anion exchange resin at room temperature, and then further diluted with MeO.
300 ml of a 70:15 (7) mixture of H:water was allowed to flow down. During this time, the flow rate is SV for strongly acidic cation exchange resin.
I adjusted it so that it was 2 hr.

In this way, 400 d of a colorless and transparent solution with a pH of 7.1 was collected. This solution consisted of polysiloxane:MeOH:water in a ratio of 6.8:75.1:18.1, and the Na ion content was 3F or less.

This product was separated, acid was added to adjust the pH, and stability under heating required for dehydration or solvent replacement was examined. Table I shows the results.
Shown below.

Table 1 *70-75°C Example 2 Polysiloxane obtained in Example 1: MeOH: Water 6
．． pH 7.1 consisting of 8: 75.1: 18.1
Acetic acid was added to a colorless and transparent solution to adjust the pf (pf) to 5.0. 200 ml of this solution was placed in a 300s +/3 flask equipped with a thermometer and a distillation tube, and placed in an oil bath. 2000 ml of MeOH containing acetic acid was supplied in a 6-hour operation, and MeOH containing 10-acetic acid was supplied from a dropping funnel to match the amount of water and Me9f to be distilled. -MeOH (1)
2000 g of the mixture was distilled off.

As a result, a MeOH solution of polysiloxane containing 1% or less of water was obtained. Furthermore, MeOH was distilled off to concentrate the polysiloxane to a concentration of 30%. This product was left at room temperature for 6 months, but no change was observed.

Example 3 In the same manner as in Example 1, pi(7,1 polysiloxa:/
: MeOH: water 7. l: 73.9: 19
．． A colorless and transparent solution consisting of 0 and containing less than 3P of Na ions 8
I got 00d.

Acetic acid was added to this solution to adjust the pH to 5.0.

Pour 100 ml of the PF (adjusted solution) into a 200 d triple flask equipped with a dropping funnel, a thermometer, and a distillation tube. Under the conditions shown in Table 2, feed the solvent shown in Table 2 through the dropping funnel, and adjust the amount supplied. The appropriate amount of water/MeOH and the fed solvent mixture were distilled off.

Note that 10 to 30 doses of acetic acid were added in advance to the supplied solvent.

As a result, a colorless and transparent polysiloxane solution containing a small amount of water and MeOH as shown in Table 2 was obtained.

*Content ratio in polysiloxane solution after solvent replacement? Acid or alkali was added to the Boria Oxa/solution obtained in Example 1 to adjust the pf (pf), and the stability under heating was examined in the same manner as in Example 1. The results are shown in Table 3.

As described above, if the pH is outside the range specified in the present invention, the polysiloxane will gel during heating and will not dissolve in the organic solvent again.

Example 4 In place of 1Viesic13 in Example 1)n, M
e S i CLst CH2=CH5iC1a KaM2
Tel: 0.27 A chisel compound was used.

The composition of the polysiloxane at this time is Meo, (CH2
=CH) o, 2S ic\ and the atomic ratio of Si and Na is 1:
An alkali salt of L2 was obtained.

An ion exchange solution 267f having a composition in which the ratio of the alkaline salt of polysiloxane, MeOH and water is 15 and 0:15 was prepared, and ion exchange was carried out in the same manner as in Example 1 with pf(6,
8. Polysiloxane: MeOH: Water 6.5: 75
．． 9: 400 ml of a colorless and transparent liquid consisting of 17.6 and Na ion concentration of 3F or less was obtained. This product was adjusted to pl-15.5 using acetic acid and kept under boiling for 5 hours, but no change was observed.

Example 5 In Example 1, EtOH was used instead of MeOH.

That is, the alkali salt of M e S iOy: EtOH
The ratio of EtOH:water in the ion exchange column was 70:15, and the extrusion liquid was a mixed solution with an EtOH:water ratio of 70=15.

As a result, pf (7,0, polysiloxane: EtOH:
A colorless and transparent solution of 400 scraps C having a composition of 6.7:75.3:18.0 of water was obtained.

This product was adjusted to pf (4.8) using acetic acid and kept under boiling for 5 hours.At the beginning of heating (a very small amount of precipitate was produced, but there was no other change).

〔Effect of the invention〕

(1) As shown in the detailed description of the present invention, when removing alkaline components from water-soluble alkali salts of polynoloxane by ion exchange, gelation etc. can be prevented during ion exchange by performing ion exchange with a specific composition. Ion exchange can be carried out in a state containing a high concentration of alkali salt without causing any inconvenience, and the amount of solvent to be removed in the wiring can be reduced from a fraction of a liter to a fraction of a liter.

(2) The pH of the solution before heating after ion exchange is adjusted to a certain range, so it is stable and does not gel even if water is distilled off by heating.

(3) The final solution contains the alcohol used in the ion exchange treatment, other alcohols, and other polar organic solvents, so it can be used for any purpose. .

Claims (1)

[Claims] (a) General formula RSiO_3_/_2 (R is C_1_~_
A solution containing a water-soluble alkali salt of polysiloxane represented by alkyl of C_2_ to_4, alkenyl, phenyl), alcohol represented by the general formula R'OH (R' is alkyl of C_1_ to_4), and water, The water-soluble alkali salt of polysiloxane in the solution is 5 to 20% by weight.
, R'OH is 30 to 90% by weight and water is 5 to 60% by weight. (b) The solution obtained by ion exchange has a pH of 3.0 to 3.0.
(c) adding alcohol or other polar organic solvent contained in the solution to the pH-adjusted solution; and (d) heating the polar organic solvent-containing solution. and distilling off a solvent containing at least water.