KR100469945B1 - Manufacturing Method of Vinyl Chlorosilane - Google Patents

Abstract

The present invention relates to a method for producing vinyl chlorosilane represented by the following formula (1), and more particularly, in the fluidized bed reaction tank or stirred reactor, the metal silicon is decomposed to vinyl chloride and hydrogen chloride or reaction during copper catalyst to generate hydrogen chloride. By directly reacting the mixed gas of alkyl chloride at a specific reaction temperature, a new and advanced process for producing vinylchlorosilane, which is very useful as a material for the preparation of silicone oil, a precursor of alkoxysilane, etc. in high yield under milder reaction conditions It is about.

[Formula 1]

In Formula 1, R ¹ represents hydrogen or chlorine.

Description

Method for producing vinyl chlorosilane

The present invention relates to a method for producing vinyl chlorosilane represented by the following formula (1), and more particularly, in the fluidized bed reaction tank or stirred reactor, the metal silicon is decomposed to vinyl chloride and hydrogen chloride or reaction during copper catalyst to generate hydrogen chloride. A new and advanced process for producing vinylchlorosilane, which is very useful as a preparation material for silicone oils, precursors of alkoxysilanes, etc. at high yields under milder reaction conditions by directly reacting mixed gases of alkyl chlorides at specific reaction temperatures. It is about.

[Formula 1]

In Formula 1, R ¹ represents hydrogen or chlorine.

Conventionally, vinylsilane compounds having a vinyl group and a Si-H bond at the same time are known to be easily polymerized through self-polymerization or self-siliconization reaction due to vinyl groups [Korshak, V. V.; Polvakova, A. M.; Mironov, V. F.; Petrov, A. D. Izvst. Akad. Nauk S.S.S.R., Otdel. Khim, Nauk, 1116, 1959].

In general, one-component silicone rubber crosslinks a silicone oil having a vinyl group with a straight-type silicone oil containing a Si-H bond and a platinum catalyst. Thus, vinylsilanes are used to prepare a silicone oil having a vinyl group. It is used as an important starting material. In addition, vinyltrichlorosilane is a precursor for the production of vinyltrialkoxysilane, and vinyltrialkoxysilane is also an important compound as a coupling agent for increasing the degree of crosslinking of the crosslinked polyethylene.

Since the introduction of US Pat. No. 2,380,995 to the production of methylchlorosilanes by direct reaction of metal silicon chloride with methane under a copper catalyst, today the silicon industry uses this technique to produce monomers.

Scheme 1

In addition to the main product dimethyldichlorosilane in Scheme 1, methyl trichlorosilane, trimethylchlorosilane, methyldichlorosilane, and the like are obtained as by-products, and the composition of these by-products depends on the catalyst, the promoter, the reaction temperature, and the reaction pressure.

Many studies have been conducted on the reaction between organic chlorides and metal silicon other than methane [Voorhoeve, R. J. H. Organohalosilanes; Precursors to Silicones, Elsevier Publishing Company, 1967. In particular, Hurd first reported on the preparation of vinylchlorosilanes by the direct reaction of vinyl chloride and metal silicon [Hurd, D. T. J. Am. Chem. Soc. 1945, 67, 1813, US Pat. No. 2,420,912 (1947). He reported that when reacted at a reaction temperature of 300-400 ° C., divinyldichlorosilane and vinyltrichlorosilane could be synthesized in yields of 10% and 20%, respectively.

Scheme 2

However, the reaction of the same method as in Scheme 2 has a low yield and is not currently used industrially.

Currently, a method of preparing vinyl silane is obtained by high-temperature condensation reaction of hydrosilane and silicon chloride having a silicon-hydrogen bond at 500 to 550 ° C., or by hydrogenation of hydrosilane and acetylene under a platinum catalyst. It is used.

However, these production methods have a disadvantage of having to undergo two-step reaction because the hydrosilane must be first synthesized by direct synthesis to obtain vinylsilane. In addition, in the case of the manufacturing method by the hydrogen silicide reaction of acetylene, expensive platinum catalyst and the pressure required for the reaction has a fatal disadvantage, such as the risk of explosion.

In the description of the direct reaction of chloroalkenes other than vinyl chloride with metal silicon, allyl chloride has the lowest production rate of diallyldichlorosilane, which is expected as the main product of the reaction, and allyldichlorosilane and allyltrichlorosilane. It has been reported to be produced as the main product. It has been reported that allyl chloride decomposes at the reaction temperature to give hydrogen chloride, which hydrogen chloride participates in the reaction to form allyldichlorosilane and allyltrichlorosilane. In addition, the small amount of diallyldichlorosilane produced is because the compound self-polymerizes at the reaction temperature to generate a polymer material, which may cause a decrease in the activity of the metal silicon.

In order to prevent such a phenomenon, Korean Patent Publication No. 95-2860 discloses an allyldichlorosilane having a silicon-hydrogen bond when a mixture of allyl chloride and hydrogen chloride is reacted with metal silicon at 220 to 350 ° C. as in Scheme 3 below. A technique for obtaining allyltrichlorosilane as a byproduct is disclosed.

Scheme 3

Another example where a mixture of hydrogen chloride and a compound having a chloromethyl group is used in the direct reaction is a reaction of a mixture of a silane compound having a chloromethyl group and a hydrogen chloride to synthesize bis (silyl) methanes, in which a silicon-hydrogen bond It is described that a bis (silyl) methane compound can be obtained as a main product [Korean Patent Application No. 91-24243].

The present invention, unlike the prior art, by using copper as a catalyst in the production method of vinyltrialkoxysilane and by reacting a mixture gas of vinyl chloride and hydrogen chloride or alkyl chloride which generates hydrogen chloride during the reaction at a specific temperature, high yield under milder conditions It is an object of the present invention to provide an improved method for preparing vinylchlorosilane, which is a target.

In the present invention, in preparing a vinylchlorosilane, a mixed gas of a vinyl chloride compound represented by the following Chemical Formula 2 and a chloride compound represented by the following Chemical Formula 3 is directly reacted with metal silicon to produce a vinylchlorosilane represented by the following Chemical Formula 1. It is characterized by that.

[Formula 1]

[Formula 2]

[Formula 3]

Among the above formula,

R ¹ represents hydrogen or chlorine,

R ² represents a lower alkyl group or a -CH ₂ CH ₂ Cl of hydrogen, chlorine, C ₁ ~C _4.

In the present invention, by directly reacting a mixed gas of vinyl chloride such as Chemical Formula 2 with hydrogen chloride or alkyl chloride such as Chemical Formula 3 with metal silicon, the desired vinyl chlorosilanes of Chemical Formula 1 may be obtained. Alkyl chloride is a compound used as a source of hydrogen chloride or chlorine by generating hydrogen chloride or chlorine under the reaction conditions. According to the present invention, examples of the compound represented by Formula 3 include hydrogen chloride, alkyl chloride having 1 to 4 carbon atoms, 1,2-dichloroethane, and the like, and vinyl trichlorosilane may be used when 1,2-dichloroethane is used. Can be obtained. In more detail, the reaction process of the present invention, using a fluidized bed reaction tank or a stirred reactor, the mixture of organic chlorides such as the formula (3) that can produce vinyl chloride and hydrogen chloride or hydrogen chloride during the reaction of metal silicon in copper catalyst 300 When directly reacted at ˜500 ° C., vinylchlorosilane may be obtained through a reaction as in Scheme 4 below. According to the present invention, in order to increase the amount of vinyldichlorosilane having a silicon-hydrogen bond, the compound of Formula 3 introduced into the compound of Formula 2 may be used in a molar ratio of 1.0 to 5.0 times, but preferably 1.0 to 3.0 times. Do. In order to increase the amount of vinyl trichlorosilane used as a precursor of the silane coupling agent, it is preferable to use chlorine or 1,2-dichloroethane. However, when using chlorine directly, it is important to remove the heat of reaction effectively because the heat of reaction is excessively generated. In the present invention, a fluidized bed reactor made of stainless steel was used, and it was possible to react continuously. Metal silicon is preferably used having a purity of 98% or more, the temperature of the reaction tank can be up to 300 ~ 500 ℃, preferably 400 ~ 450 ℃. The reaction pressure can be used up to 6 kg / ㎠ at normal pressure and the higher the pressure, the faster the reaction rate. Meanwhile, in the present invention, as a catalyst, copper or copper compounds capable of producing copper under reaction conditions may be used. The amount of copper used is 5-10% of the total weight of the contact mixture. In addition, the use of 0.001 to 5% of a cocatalyst relative to the copper catalyst can increase the reaction rate and enhance the selectivity of a specific compound. Cocatalysts for this reaction may include, but are not limited to, zinc, cadmium, titanium, manganese, magnesium, silver, tin, and the like.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited by Examples.

Example 1

124.6 g of cuprous chloride (CuCl) was put in a mortar and finely ground. After mixing finely with 720 g of metal silicon, the mixture was placed in a reactor. After raising the temperature of the reactor to 270 ° C, flowing dried nitrogen at a rate of 300 ml / min. Allowed to dry for 2 hours. After drying, the temperature of the reaction tank is heated to 370 ° C. or higher to produce tetrachlorosilane as a by-product as a reaction product, and a highly active Si-Cu contact mixture is produced. The mixture is maintained at this temperature for 3 hours to prepare a contact mixture. Phosphorus tetrachlorosilane was received. In the case of using zinc as a promoter other than copper as the main catalyst, after the preparation of the contact mixture was completed, the temperature of the reactor was lowered to room temperature under nitrogen atmosphere, and then the required amount of promoter was added from the upper part of the reactor and the temperature was well mixed. .

Example 2

720 g of metal silicon and 80 g of copper catalyst are mixed well, dried at 300 ° C. for about 2 hours, the temperature of the reactor is raised to 350 ° C., and methane chloride is introduced into the reactor from below. After about 1 hour, dimethyldichlorosilane and methyltrichlorosilane, which are reaction products, are generated and collected in the flask. They are starting to produce evidence that a contact mixture of Si-Cu is being produced. After reacting with methane chloride for about 2 hours, the supply of methane chloride is stopped and a promoter is required in the same manner as in Example 1 above. A promoter was added and used for the reaction.

Example 3

4 g of cadmium was added to 800 g of the contact mixture prepared in Example 2 as a cocatalyst in a fluidized bed reactor, and the reaction temperature was raised to 420 ° C., and vinyl chloride was added to 183 ml / min. While blowing at a rate of 1.473 mole / hr, hydrogen chloride was introduced into the reactor at a rate of 550 ml / min (2.946 mole / hr). At this time, the dried nitrogen was used together at a rate of 400 ml / min to help fluidize the contact mixture.

Immediately after the start of the reaction, an increase in temperature due to exothermic reaction was observed, and the reaction product began to collect in the receiving flask installed in the upper part of the reactor. The reaction product was received every hour while maintaining these reaction conditions. The vinyl chloride used for the reaction for 3 hours was 276 g and the total amount of reaction product obtained was 486 g.

The resulting reaction product was analyzed using gas chromatograph and separated through the fractional distillation. Fractional distillation produced 181 g (37%) of vinyldichlorosilane and 155 g (32%) of vinyltrichlorosilane. Other byproducts were 85 g (18%) and 12 g (3) of trichlorosilane and tetrachlorosilane, respectively. %) Was generated. Other high boiling point compounds contained about 10%.

Example 4

800 g of the contact mixture prepared in Example 1 and 4 g of cadmium were added to a fluidized bed reactor as a cocatalyst and reacted under the same reaction conditions as in Example 3. The amount of reaction product obtained in the reaction for 3 hours was 452 g.

Analysis of the reaction product yielded 136 g (30%) of vinyldichlorosilane, 167 g (37%) of vinyltrichlorosilane, 90 g (20%) of trichlorosilane, and 23 g (5%) of tetrachlorosilane. 8% of the high boiling point compound was produced.

Example 5

Using the contact compound prepared in Example 2, the reaction result of only changing the reaction temperature in the same reaction conditions as in Example 3 is listed in Table 1 below.

TABLE 1

Example 6

Table 2 shows the results of reacting only the molar ratio of vinyl chloride and hydrogen chloride in the reaction conditions as in Example 3 using the contact mixture prepared in Example 2.

TABLE 2

Example 7

Using the contact mixture prepared in Example 2, only the reaction pressure was changed in the same reaction conditions as in Example 3, and the results are shown in Table 3 below.

TABLE 3

Example 8

The reaction mixture prepared in Example 2 was reacted under the same reaction conditions as in Example 3, but the reaction results using various organic chlorides instead of hydrogen chloride as a source of hydrogen chloride are shown in Table 4 below. The same result was obtained when the amount of the organic chloride was reduced by half and the amount of hydrogen chloride used was reduced.

TABLE 4

As described above, the production method according to the present invention has the effect of producing a high yield of vinyl chlorosilane in a simpler and more economical conditions than conventional.

Claims (13)

In preparing vinylchlorosilane, In the presence of a metal silicon, a copper catalyst and a cadmium promoter, the vinyl chloride compound represented by the following formula (2) and the chloride compound represented by the following formula (3) have a reaction pressure of atmospheric pressure to 6 kg / cm 2 and a reaction temperature range of 400 to 450 ° C. Method for producing a vinyl chlorosilane represented by the following formula 1 characterized in that it is prepared by direct reaction in: [Formula 1] [Formula 2] [Formula 3] Among the above formula, R ¹ represents hydrogen or chlorine, R ² represents a lower alkyl group or a -CH ₂ CH ₂ Cl of hydrogen, chlorine, C ₁ ~C _4. The method of claim 1, wherein the chemical formula (3) is hydrogen chloride. The method of claim 1, wherein the chemical formula 3 is chlorine. The method of claim 1, wherein R ² of the formula (3) is an isopropyl group. The method of claim 1, wherein R ² of Formula 3 is a normal propyl group. The method of claim 1, wherein R ² of Formula 3 is a t-butyl group. The method of claim 1, wherein R ² of Formula 3 is a normal butyl group. The method of claim 1, wherein R ² of the formula (3) is a chloroethyl group. The method of claim 1, wherein the chemical formula 3 is used in a molar ratio of 0.5 to 5.0 times with respect to the chemical formula 2. The method of claim 1, wherein the compound of Formula 3 is mixed with hydrogen chloride and another compound of Formula 3 for use in the reaction. The method of claim 1, wherein the reaction is carried out using a fluidized bed reactor or a stirred reactor. The method for producing vinylchlorosilane according to claim 1, wherein 1 to 30% by weight of a metal copper or a compound capable of liberating copper under reaction conditions is used as a catalyst. The method of claim 12, wherein the cadmium promoter is used in an amount of 0.001 to 5% by weight based on the total weight of the contact mixture.