JPS63172702A - Method of chlorination or chlorination and chlorosulfonation - Google Patents

Abstract

PURPOSE:To obtain a high-quality product with good production efficiency, which will not result in a deteriorated colored polymer, by dissolving a polyolefin or a rubber in a solvent in a reactor, by chlorinating and, if desired, chlorosulfonating and by circulating the distilled solvent under heating. CONSTITUTION:A polyolefin or a rubber (e.g., high-density PE) is introduced into a reactor 1 of equipment made of a corrosion-resistant material, for example, glass lining, Karbate, Teflon resin lining, or Hastelloy, and a solvent (e.g., CCl4) which has been heated to about 110 deg.C in a heat exchanger 5 for solvent is added to dissolve it, followed by continuous addition of a solution in which a catalyst, for example azobisisobutyronitrile, has been dissolved. Then, if desired, a chlorosulfonating cocatalyst (e.g., pyridine) is added, and sulfuryl chloride, chlorine gas or SO2 is introduced to effect the reaction of chlorination or the reactions of chlorination and chlorosulfonation. The distilled solvent is condensed by a reflux condenser 2, collected into a solvent reservoir 3 and a solvent tank 4, and a prescribed amount of it is transferred to a heat exchanger 5 via a flow control valve 9 etc. to be heated, and the circulated to the reactor 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to chlorination of polyolefins or rubbers or a reaction method for producing chlorosulfonated products.

[Prior Art] Chlorinated or chlorinated and chlorosulfonated products of polyolefins and rubbers are often produced by a solution method in which a polymer is dissolved in a solvent and reacted because a reactant with uniform quality can be obtained.

In this method, in order to carry out the reaction efficiently, it is necessary to continuously discharge hydrogen chloride produced by the reaction and unreacted gas to the outside of the system to allow the reaction to proceed. At this time, the wIW together with the by-product gas undergoes IR, but the solvent is usually refluxed in a condenser attached to the reactor and returned to the reactor. This method is important in order to prevent abnormal progression of the reaction due to changes in the composition of the reaction system due to distillation of the solvent out of the system, and to prevent a decrease in stirring power due to an increase in the viscosity of the system. In order to prevent this, it is necessary to keep the temperature in the condenser as low as possible to prevent the solvent from distilling out of the system. In this case, since the cooled solvent flows back into the reactor, it becomes difficult to keep the reaction temperature constant unless the jacket of the reactor is heated. However, it is difficult to heat a highly viscous reaction liquid by heating from the reactor jacket, and it is necessary to heat the reaction liquid at a high temperature.

In addition, as the reaction progresses or by repeating the reaction, highly viscous polymers adhere to the inner walls of the reactor.These polymers deteriorate and become colored due to heating of the reactor jacket, and some of them are added to the reaction solution. This will cause contamination and reduce the quality of the reactants. Therefore, these deposits are removed by periodically cleaning the reactor, and those mixed into the reaction solution are removed using a strainer or the like to produce the final product.

Therefore, it can be said that it is desirable that the chlorination or chlorination and chlorosulfonation reaction of the polymer be carried out with as little external heating as possible.

One such method is to keep the reaction temperature constant using only the reaction heat. That is, it is conceivable to suppress the discharge of by-product gases produced by the reaction as much as possible, and also to reduce the distillation of the solvent. For this purpose, it is necessary to increase the pressure during the reaction, but the increase in reaction pressure changes the reaction rate, making it difficult to obtain the desired chlorine and sulfur contents.

It has also been proposed to carry out some of the processes that are likely to produce degraded polymers at low temperatures.

(JP 61-118408) That is, after the reaction is completed,
This is a method in which by-product gases remaining in the reaction system are removed by keeping the jacket and internal temperatures the same.

However, these methods cannot be said to be perfect either because it is difficult to obtain the desired product or because the operations are complicated.

[Problems to be Solved by the Invention] In the production of such chlorinated or chlorinated and chlorosulfonated polyolefins or rubbers, the present invention solves the following problems:
The object of the present invention is to provide a reaction method for preventing contamination of derived degraded polymers.

[Means for Solving the Problems J] In the present invention, in order to maintain the reaction temperature when the chlorination or chlorination and sulfonation reactions of polyolefins or rubber are carried out using a solvent, direct heating is performed from the reactor jacket. The objective is to provide a reaction method that can be carried out without having to do so.

That is, the present invention heats the solvent distilled from the reaction system in the above reaction using a heat exchanger, and then introduces it into the reactor to adjust the reaction temperature, thereby reducing the amount of degraded polymer derived from direct heating of the reactor. There is a reaction method to prevent the occurrence.

The apparatus used in the reaction method of the present invention is a reactor.

Reflux condenser and solvent receiver attached to the reactor.

It consists of a solvent tank, a solvent heat exchanger, a pump, a 1/1 valve, etc. In order to cope with the corrosive gas generated by the reaction, glass lining, carbide, Teflon resin lining, and corrosion-resistant metal materials such as Hastelloy and tantalum are used.

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

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

In addition, if necessary, by adjusting the amount of solvent reintroduced into the reactor, the viscosity of the reaction solution can be adjusted or the reaction solution can be concentrated, thereby changing the proportion of the solvent in the reaction solution. Cover with gas. This can improve the throughput of drum dryers, vented extrusion dryers, etc., which are commonly used to separate and dry the reactants from the reaction liquid.

The raw material polyolefins to be reacted in the present invention include ethylene homopolymers, ethylene and propylene, butene-1, pentene-1, hexene-1,4-methyl
Copolymers of pentene-1, vinyl acetate, acrylic acid, and alkyl acrylates can be used, and as rubbers, polybutadiene, polyisoprene, polybutylene,
Dityrene-butadiene copolymer, ethylene-propylene-diene copolymer, etc. can be used.

As a reaction solvent for dissolving these polymers,
Carbon tetrachloride, a halogenated hydrocarbon.

Trichlorethylene, tetrachloroethane, trichlorobenzene, etc. are used alone or in combination.

Chlorine, sulfuryl chloride, chlorine and sulfur dioxide gas, sulfuryl chloride, and chlorine are used as the chlorination or chlorinating and chlorosulfonating agent.

Catalysts for starting the reaction include azobisisobutyronitrile, 2.2'azobis2.4dimethylu? Azo compounds like leronitrile.

Peroxides such as benzoyl peroxide and dilauroyl peroxide are used.

Further, an amine compound such as pyridine or quinoline is used as a co-catalyst.

The reaction is carried out by dissolving the polyolefin or rubber in a solvent, adding a catalyst, chlorination or chlorinating and chlorosulfonating agent, and reacting to add the specified MA element and sulfur, and then dissolve the remaining in the system. After removing the acid content using an inert gas such as nitrogen, bisphenol A
A stabilizer such as a type epoxy compound is added, and then the solvent and reactant are separated using a drum dryer, vented extrusion dryer, etc. to obtain a chlorinated or chlorinated and chlorosulfonated polyolefin or rubber.

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

With this method, it is possible to control the amount of solvent distilled from the reflux condenser that is reintroduced into the reactor, and it is possible to increase the processing capacity when separating reactants and solvent from the reaction solution. There are advantages.

[Examples] Aspects of the present invention will be illustrated below using Examples, but the present invention is not limited thereto.

Example 1 An example of the reaction of polyethylene according to the flow shown in Figure 1 is shown. High density polyethylene 100* with a density of 0.963 and a melt flow rate of 5.0 in a 10001 reactor
Then, 1000 carbon tetrachloride heated to 110° C. using a solvent heat exchanger having an electric heating area of 1.5 d was added and dissolved. Next, a solution of α,α'-azobisisobutyronitrile in carbon tetrachloride was continuously added.

Subsequently, sulfuryl chloride was introduced into the reactor at a rate of 301/hour, and 0.2 cod of pyridine was added as a cocatalyst for the chlorosulfonation reaction. When the reaction starts, the reactor pressure increases, so the pressure is adjusted to 3.5Ky/gauge pressure using the pressure regulating valve.
Adjusted to d. Carbon tetrachloride was distilled into the reflux condenser and received into the solvent receiving tank. The liquid flow m from the solvent tank is
The flow rate was controlled by a flow control valve. Carbon tetrachloride is heated to a reaction temperature of 100°C using a solvent heater in an amount corresponding to the amount distilled from the reactor.
The mixture was heated to a temperature of Reaction temperature 100℃
The amount of carbon tetrachloride distilled from the vent condenser was approximately 50 l/hr.

During the reaction, the pressure of the reaction system was adjusted using a pressure regulating valve, and the reaction temperature was maintained at 100° C. without heating the reactor jacket. When chlorination and chlorosulfonation reached predetermined values (MA element content 35 f! mass%, sulfur content 1.0 mass%), the sulfuryl chloride and catalyst liquid were stopped and the pressure of the reaction system was lowered with a pressure regulating valve. . When the pressure reached a gauge pressure of 0.5 kg/cl11 yen, nitrogen gas was introduced from the bottom of the reactor at 3 Nd/HR to remove any by-product gas remaining within the prefecture. Carbon tetrachloride refluxed from the reactor was heated through a solvent heat exchanger so that the temperature inside the reactor was 70 to 80° C. and introduced into the exchanger in the same manner as during the reaction. After this operation was carried out for 3 hours, bisphenol A type epoxy resin 2K'J was added as a stabilizer, and the chlorosulfonated polyethylene was separated and dried using a drum dryer in a conventional manner. After carrying out this reaction operation 30 times in succession, the interior of the reactor was inspected, and it was found that almost no polymer was found adhering to the interior walls, and no colored polymer was found. Moreover, no colored material was observed in the chlorinated and peroxysulfonated polyethylene obtained by separation and drying.

Example 2 In Example 1, the reaction temperature was 110°C and the reaction pressure was 2
．． After setting the gauge to 5Kg/cd and starting the continuous addition of the azobisisobutyronitrile catalyst solution, chlorine gas was added from the bottom of the reactor at a rate of 5NTIt/HR until the chlorine content of polyethylene was 35% by weight. . The amount of tetraradical carbon distilled out from the reactor during the reaction was approximately 601 per unit time. An appropriate amount of carbon tetrachloride was heated as in Example 1 and introduced into the reactor.

Next, this reaction was repeated in the same manner as in Example 1, and the inside of the reactor and the product were inspected for adhesion and contamination of colored substances and degraded polymers, but as in Example 1, no contamination of these colored substances was observed.

Example 3 In the same manner as in Example 2, 5Nd/chlorine gas was supplied from the bottom of the reactor.
After chlorinating the blown polyethylene at a rate of HR to a chlorine content of 17% by weight, 0.2 Ky of pyridine was added, and then sulfuryl chloride was added and reacted in the same manner as in Example 1. The reaction treatment was carried out in the same manner as in Example 1 except that the reaction pressure was maintained at 4.5 Ky/cd.
Chlorinated and chlorosulfonated polyethylene with a sulfur content of 1.0% by weight was obtained.

Next, this reaction was repeated in the same manner as in Example 1, and the inside of the reactor was inspected, and the coloration of the degraded polymer in the chlorinated and polysulfonated polyethylene was inspected.As a result, colored substances,
No adhesion of degraded polymer to the reactor or contamination with the polymer was observed.

Comparative Example 1 In Example 1, refluxing carbon tetrachloride was made to flow directly into the reactor through the reflux condenser attached to the reactor, and 150°C steam was introduced into the jacket, thereby converting 100Kl of polyethylene into tetracarbons. Carbon 100 (
The mixture was dissolved and reacted in 1 hour for about 1 hour. During the reaction, steam was introduced into the jacket to heat the reaction solution to maintain it at 100°C. To keep the temperature of the reaction solution constant, set the jacket temperature to 1.
It was necessary to maintain the temperature between 20 and 150°C, and the pressure in the reactor had to be maintained at approximately 3.5 Ng/csl gauge pressure.

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 in the same manner as during the reaction. Example 1
This operation was repeated 30 times, and when inspected in the same way, it was found that the inner wall of the reactor was coated with a colored polymer about 3 feet thick, of which 1 JII layer was attached to the inner wall of the reactor.
I was discolored to black or brown. In addition, these colored substances were mixed into the obtained product.

Comparative Example 2 A reaction treatment was carried out in the same manner as in Example 2, except that, as in Comparative Example 1, a line was set to directly return the carbon tetrachloride refluxing from the reflux condenser attached to the reactor into the reactor. Next, the reaction was repeated in the same manner as in Example 1, and when the inside of the reactor was inspected, it was found that about 2jlllI of polymer had adhered to the inner wall, and about 1 am of it was brown to brown in color.

[Effects of the Invention] As is clear from the above description, according to the present invention, deterioration occurs in the reactor during polymer chlorination or chlorination and chlorosulfonation reactions.

The generation of colored polymers can be prevented, resulting in improved product quality, and production efficiency can be improved by changing the concentration of the reaction solution.

[Brief explanation of the drawing]

FIG. 1 shows a conceptual diagram of the chlorination or chlorination and chlorosulfonation reaction apparatus according to the present invention. 1... Reactor 2... Reflux condenser 3... Solvent receiving tank 4... Solvent tank 5... Solvent heat exchanger 6... Harm removal tower 7... Pressure adjustment valve 8.9 ...Flow control valve io,'+i...Solvent pump 12...Level detector 13.14...Flow port detector Patent applicant Toyo Soda Kogyo Co., Ltd. Figure-1

Claims (1)

[Claims] 1) In a reaction in which polyolefin or rubber is dissolved in a solvent in a reactor and chlorinated or chlorinated and chlorosulfonated using sulfuryl chloride, chlorine gas, sulfur dioxide gas, or a combination of these. , a chlorination or chlorination and chlorosulfonation reaction method, characterized in that the solvent distilled from the reactor is heated with a heat exchanger and then introduced into the reactor. 2) Claim 1, in which the solvent distilled from the reactor is condensed in a condenser and then introduced into the solvent receiving tank.
Chlorination or chlorination and chlorosulfonation reaction method described in Section 1.