JPH0717699B2 - Chlorination or chlorination and chlorosulfonation reaction method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a reaction method for producing a chlorinated or chlorinated polyolefin or rubber and a chlorosulfonate.

[Prior Art] Chlorinated or chlorinated polyolefins and rubbers and chlorosulfonates are mostly produced by a solution method in which a polymer is dissolved in a solvent for reaction because a reaction product having a uniform quality can be obtained.

In this method, in order to carry out the reaction efficiently, it is necessary to continuously discharge the hydrogen chloride and unreacted gas, which are by-products of the reaction, out of the system to allow the reaction to proceed. At this time, the solvent evaporates together with the by-product gas, but normally the solvent is refluxed by the condenser attached to the reactor and returned to the inside of the reactor. This method is important in order to prevent the progress of the reaction from being abnormal due to the change in the composition of the reaction system due to the solvent being distilled out of the system, and to prevent the stirring power from being lowered due to the increase in the viscosity of the system. In order to prevent such a thing, it is necessary to lower the temperature in the condenser as much as possible to prevent the solvent from being distilled out of the system. In this case, since the cooled solvent is refluxed into the reactor, it is difficult to keep the reaction temperature constant unless the jacket of the reactor is heated. However, it is difficult to heat the reaction liquid having a high viscosity by heating from the reactor jacket, and it is necessary to heat at a high temperature.

Also, with the progress of the reaction or by repeating the reaction, a highly viscous polymer adheres to the inner wall of the reactor, but these are deteriorated by the heating of the reactor jacket and are colored, and a part of the polymer remains in the reaction solution. It mixes and deteriorates the quality of the reaction product. Therefore, these deposits are regularly removed by washing the reactor, and those mixed in the reaction solution are removed by a strainer or the like to obtain the final product.

Therefore, it can be said that it is desirable that the chlorination or chlorination and chlorosulfonation reaction of the polymer is carried out without heating from the outside as much as possible. As one of such methods, it is considered that the reaction temperature is kept constant only by the heat of reaction. That is, it is conceivable to suppress the discharge of the by-product gas generated by the reaction as much as possible and reduce the amount of the solvent distilled. For that purpose, it is necessary to increase the pressure during the reaction, but there is a drawback that the reaction rate changes due to the increase in the reaction pressure, and it is difficult to obtain the desired chlorine and sulfur contents.

In addition, an attempt has also been proposed in which a part of the process in which deterioration polymer is considered to be produced is carried out at a low temperature. (JP-A-61-11
No. 8408), that is, in the operation of removing the by-product gas remaining in the reaction system after the reaction is completed, the temperature inside the jacket is made equal to that inside.

However, these methods cannot be said to be perfect in any case because it is difficult to obtain a desired product and operation is complicated.

[Problems to be Solved by the Invention] The present invention relates to the production of such a chlorinated or chlorinated and chlorosulfonated polyolefin or rubber.
It is an object of the present invention to provide a reaction method for preventing contamination of a deteriorating polymer.

[Means for Solving Problems] In the present invention, in order to maintain the reaction temperature when carrying out the chlorination or chlorination and chlorosulfonation reaction of a polyolefin or rubber, heating is carried out directly from the reactor jacket. It is to provide a reaction method to be carried out without.

That is, in the present invention, the solvent distilled from the reaction system in the above reaction is heated by a heat exchanger, and then introduced into the reactor to adjust the reaction temperature, thereby degrading the deteriorated polymer derived by direct heating of the reactor. It is a reaction method to prevent the generation.

The apparatus used in the reaction method of the present invention comprises a reactor, a reflux condenser attached to the reactor, a solvent receiving tank, a solvent tank, a solvent heat exchanger, a pump, a regulating valve and the like. These are made of glass lining, carbate, Teflon-based resin lining, or hastelloy or tantalum made of a metal material having corrosion resistance to cope with corrosive gas generated by the reaction.

As the structure of the heat exchanger for solvent, a multi-tube type, a double-tube type, a coil type or the like can be used.

The solvent is introduced into the reactor through the solvent heat exchanger by spraying from the top of the reactor to add it, or by directly introducing it into the reaction solution.

Also, if necessary, by adjusting the amount of the solvent to be re-introduced into the reactor, the viscosity of the reaction solution can be adjusted or the reaction solution can be concentrated to change the ratio of the solvent in the reaction solution. You can This can improve the processing ability in a drum dryer, a vented extruder, or the like, which is usually performed to separate and dry the reaction product from the reaction liquid.

As the raw material polyolefin to be reacted in the present invention, ethylene homopolymer, ethylene and propylene, butene-1, pentene-1, hexene-1, 4-methylpentene-1, vinyl acetate, acrylic acid and alkyl acrylate, etc. As the rubber, for example, polybutadiene, polyisoprene, polybutylene, styrene-butadiene copolymer, ethylene-propylene-diene copolymer and the like can be used.

As a reaction solvent for dissolving these polymers,
Halogenated hydrocarbons such as carbon tetrachloride, trichloroethylene, tetrachloroethane and chlorobenzene may be used alone or in combination.

As the chlorinating or chlorinating and chlorosulfonating agent, chlorine, sulfuryl chloride, chlorine and sulfurous acid gas, sulfuryl chloride and chlorine are used.

As the catalyst for initiating the reaction, azo compounds such as azobisisobutyronitrile and 2,2′azobis2,4dimethylvaleronitrile, and peroxides such as benzoyl peroxide and dilauroyl peroxide can be used. Used.

An amine compound such as pyridine or quinoline is used as a cocatalyst.

The reaction is carried out by dissolving a polyolefin or rubber in a solvent by a conventional method, adding a catalyst, chlorination or a chlorination and a chlorosulfonating agent, reacting, adding a predetermined amount of chlorine and sulfur, and then remaining in the system. After removing the acid component with an inert gas such as nitrogen, a stabilizer such as a bisphenol A type epoxy compound is added, and then the solvent and the reaction product are separated using a drum dryer or a vented extruder, A chlorinated or chlorinated and chlorosulfonated polyolefin or rubber is obtained.

[Operation] In the chlorination or chlorination and chlorosulfonation reaction by the method of the present invention, the reflux condenser attached to the reactor was used to separate the by-product gas and the solvent as much as possible, and the separated reflux solvent was received in another container. After that, by heating again with a heat exchanger and introducing it into the reactor, it can be carried out at a constant temperature without heating the jacket of the reactor.

According to this method, it is possible to adjust the amount of the solvent distilled from the reflux condenser to be reintroduced into the reactor, and it is possible to increase the processing capacity in separating the reaction product and the solvent from the reaction solution. There are advantages.

[Examples] Examples of the present invention are shown below, but the present invention is not limited thereto.

Example 1 A reaction example of polyethylene according to the flow shown in FIG. 1 is shown. In a 1000 reactor, 100 kg of high density polyethylene having a density of 0.963 and a melt flow ratio of 5.0 was placed, and then 1000 kg of carbon tetrachloride heated to 110 ° C. was dissolved in a solvent heat exchanger having an electric heating area of 1.5 m ² . Then α, α'-
A solution of azobisisobutyronitrile dissolved in carbon tetrachloride was continuously added. Then, sulfuryl chloride was introduced into the reactor at a rate of 30 / hour, and 0.2 kg of pyridine was added as a cocatalyst for the chlorosulfonation reaction. Since the reactor pressure rises when the reaction starts, the pressure was adjusted to a gauge pressure of 3.5 kg / cm ² with a pressure control valve. Carbon tetrachloride was distilled out to the reflux condenser and received in the solvent receiving tank. The amount of liquid sent from the solvent tank was adjusted by a flow rate adjusting valve. Carbon tetrachloride was heated in a solvent heater at an amount corresponding to the amount distilled from the reactor so that the reaction temperature was 100 ° C., and was introduced into the reactor. The amount of carbon tetrachloride distilled from the vent condenser at a reaction temperature of 100 ° C. was approximately 50 / hour.

During the reaction, the pressure of the reaction system was adjusted by the pressure control valve, and the reaction temperature was kept at 100 ° C. without heating the jacket of the reactor. When the chlorination and chlorosulfonation reached the predetermined values (chlorine content 35% by weight, sulfur content 1.0% by weight), sulfuryl chloride and the catalyst solution were stopped, and the pressure of the reaction system was lowered by the pressure control valve. Pressure is 0.5kg / gauge pressure
When it reaches about ² cm3, nitrogen gas from the bottom of the reactor is ³ Nm ³ / HR.
Was introduced to remove the by-product gas remaining in the system. Carbon tetrachloride refluxed from the reactor, in the same manner as during the reaction,
It was heated to a temperature of 70 to 80 ° C. through a solvent heat exchanger and introduced into the exchanger. After carrying out this operation for 3 hours, 2 kg of a bisphenol A type epoxy resin was added as a stabilizer, and chlorosulfonated polyethylene was separated and dried by a drum dryer by a conventional method. After repeating this reaction operation 30 times continuously, the inside of the reactor was inspected. As a result, almost no adhering polymer was found on the inner wall surface and no colored polymer was found. In addition, the chlorinated and chlorosulfonated polyethylene obtained by separation and drying did not show any colored matter.

Example 2 In Example 1, the reaction temperature was 110 ° C. and the reaction pressure was 2.5 kg.
/ cm ² gauge, and after starting the continuous addition of the azobisisobutyronitrile catalyst solution, chlorine gas was added from the bottom of the reactor at a rate of 5 Nm ² / HR to obtain a chlorine content of 35% by weight of polyethylene. Chlorination was performed. The amount of carbon tetrachloride distilled out of the reactor during the reaction was about 60 per unit time. Carbon tetrachloride suitable for this was heated in the same manner as in Example 1 and introduced into the reactor.

Then, this reaction was repeated in the same manner as in Example 1 to check the adherence and mixing of the coloring matter and the deteriorated polymer in the reactor and the product, but as in Example 1, the mixing of these coloring matters was not observed.

Example 3 As in Example 2, chlorine gas from the bottom of the reactor was 5 Nm ² / HR.
After chlorinating polyethylene at a rate of 17% by weight to a chlorine content of 17% by weight, 0.2 kg of pyridine was added, and then sulfuryl chloride was added and reacted in the same manner as in Example 1. At this time, the reaction pressure was kept at 4.5 kg / cm ² , and the reaction treatment was carried out in the same manner as in Example 1 to obtain chlorinated and chlorosulfonated polyethylene having a chlorine content of 35% by weight and a sulfur content of 1.0% by weight.

Then, this reaction was repeated in the same manner as in Example 1 to inspect the inside of the reactor, to check the coloring of the deteriorated polymer in the produced chlorinated and chlorosulfonated polyethylene.
Degraded polymer was not attached to the reactor or mixed with the polymer.

Comparative Example 1 Carbon tetrachloride which was refluxed by a reflux condenser attached to the reactor in Example 1 was directly refluxed into the reactor, and steam of 150 ° C. was introduced into a jacket to introduce 100 kg of polyethylene into 1000 kg of tetrachlorinated carbon. It was dissolved and reacted for about 1 hour. During the reaction, steam was put in the jacket and heated to keep the reaction solution at 100 ° C. In order to keep the temperature of the reaction solution constant, it is necessary to keep the jacket temperature at 120 to 150 ° C, and the reactor pressure is about 3.5 kg / cm in gauge pressure.
^Had to keep to ² .

After the reaction was completed, the by-product gas in the reaction solution was removed in the same manner as in Example 1, but the temperature of the reaction solution decreased unless the jacket was heated at the same time as during the reaction. Example 1
This operation was repeated 30 times in the same manner as above, and the same inspection was carried out.A colored polymer with a thickness of about 3 mm was attached to the inner wall of the reactor, of which about 1 mm in contact with the jacket was discolored black or brown. . In addition, these colored substances were mixed in the obtained product.

Comparative Example 2 As in Comparative Example 1, a reaction process was carried out in the same manner as in Example 2 except that a line was set so that the refluxing carbon tetrachloride was directly returned from the reflux condenser attached to the reactor into the reactor. Then, the reaction was repeated in the same manner as in Example 1, and when the inside of the reactor was inspected, about 2 mm of polymer adhered to the inner wall, of which about 1 mm was brown or brown.

[Effects of the Invention] As is apparent from the explanation of abnormalities, according to the present invention, it is possible to prevent deterioration occurring in the reactor in the chlorination of polymers or chlorination and chlorosulfonation reactions and generation of colored polymers, and product quality. And the production efficiency can be improved by changing the reaction solution concentration.

[Brief description of drawings]

FIG. 1 shows a conceptual diagram of a chlorination or chlorination and chlorosulfonation reactor according to the present invention. 1 ... Reactor 2 ... Reflux condenser 3 ... Solvent receiving tank 4 ... Solvent tank 5 ... Solvent heat exchanger 6 ... Detoxification tower 7 ... Pressure adjusting valve 8, 9 ... Flow rate adjusting valve 10, 11 …… Solvent pump 12 …… Level detector 13,14 …… Flow rate detector

Claims (3)

[Claims] 1. A reactor in which a polyolefin or a rubber is dissolved in a solvent in a reactor and sulfuryl chloride, chlorine gas, sulfurous acid gas, or a combination thereof is used for chlorination or chlorination and chlorosulfonation. After heating the solvent to be distilled off with a heat exchanger,
A chlorination or chlorination and chlorosulfonation reaction method, characterized by being introduced into a reactor. 2. The method for chlorination or chlorination and chlorosulfonation according to claim 1, wherein the solvent distilled from the reactor is condensed with a condenser and then introduced into a solvent receiving tank. 3. The chlorination or chlorination and chlorosulfone according to claim 2, wherein the amount of the solvent transferred from the solvent receiving tank to the reactor and the amount of the solvent transferred from the solvent tank to the reactor are controlled by a flow rate control valve. Reaction method.