JPS6410522B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing powdered rubber comprising a chlorosulfonated ethylene polymer and a diene polymer.

More specifically, a halogen-containing organic solvent solution containing a chlorosulfonated ethylene polymer obtained by chlorosulfonation of an ethylene polymer by a solution method is aqueous emulsified with a cationic surfactant, and then the organic solvent is The resulting cationic latex is mixed dropwise into a mixed solution of a water-soluble anionic polymer compound and anionic diene polymer latex to form a co-powder of the chlorosulfonated ethylene polymer and diene polymer. The present invention relates to a method for producing a powdered rubber comprising both of the above polymers by adding a synthetic resin emulsion thereto, followed by dehydration and drying.

Chlorosulfonated ethylene polymers are generally said to have the best properties when manufactured by a solution method, which involves dissolving the ethylene polymer in an organic solvent, such as a halogen-containing organic solvent.
It is produced by chlorosulfonation using chlorine and sulfur dioxide gas or chlorine and sulfuryl chloride to contain 10 to 60% chlorine and 0.5 to 4.0% sulfur.

This chlorosulfonated ethylene polymer is generally produced by reacting in a solution as described above, contacting it with steam, removing the solvent, and then drying it, or removing the solvent and drying it on a heated drum. After this process, it is supplied in the form of chips or bales for various purposes.

In addition to being used alone, chlorosulfonated ethylene polymers are used in combination with other diene polymers and synthetic resins to impart heat resistance and flame retardancy, or to improve processability. This is also one of its important uses. Particularly in the fields of paints and adhesives, in order to fully exhibit this blending effect and because it is often used as a solution, the chlorosulfonated ethylene polymer in the form of chips or veils is further shredded and mixed with other diene. Mixing with other polymers and the like is practiced. In addition, one of the applications that takes advantage of the properties of chlorosulfonated ethylene polymer is in the field of coating agents and waterproofing agents, for example, by alternately mixing a solution of chlorosulfonated ethylene polymer with a solution of other diene polymers or synthetic resins. Repeated application is performed. Even in this case, since these rubbers are in the form of chips or veils, much labor is required for solution preparation and processing operations. In order to overcome such manufacturing and processing difficulties, it is desirable to use a powder in which the chlorosulfonated ethylene polymer and other diene polymers are mixed. This can solve many of the problems mentioned above.

The present invention has been made as a result of intensive research based on such an objective, and has been developed by chemically treating a halogen-containing organic solvent solution containing a chlorosulfonated ethylene polymer obtained by a solution method and a diene polymer.
We succeeded in producing a mixture by co-powdering both polymers in a desired ratio. That is, the present invention involves aqueous emulsification of a halogen-containing organic solvent solution of a chlorosulfonated ethylene polymer obtained by a chlorosulfonation reaction of an ethylene polymer by a solution method with a cationic surfactant; The latex of chlorosulfonated ethylene polymer (A) obtained by removing
and (B) and 0.1 to 10 parts by weight of a water-soluble anionic polymer compound per 100 parts by weight in total to form a co-powder of the chlorosulfonated ethylene polymer and diene polymer. , and then add 0.5 to 20 parts per 100 parts by weight of the polymers (A) and (B).
This is a method for producing a powdered rubber made of a chlorosulfonated ethylene polymer and a diene polymer, which is characterized by adding an emulsion containing parts by weight of a synthetic resin, followed by dehydration and drying.

The present invention will be explained in more detail below.

The raw material for the chlorosulfonated ethylene polymer to be powdered in the present invention is a reaction product solution containing a chlorosulfonated ethylene polymer obtained by chlorosulfonation of an ethylene polymer by a solution method as described above. A halogen-containing organic solvent solution containing coalescence is used. A method for obtaining this chlorosulfonated ethylene polymer-containing halogen-containing organic solvent solution is already known, and an outline thereof will be described below. As the ethylene polymer, linear polyethylene or branched polyethylene having a melt index of 0.1 to 200, or a copolymer of ethylene and an ethylenic comonomer copolymerizable therewith can be used. Preferred comonomers include vinyl acetate, propylene, butene-1, and acrylic acid. These can be used up to 50% by weight, based on total monomers.

Next, as a solvent for dissolving these ethylene polymers and chlorosulfonation, a halogen-containing organic solvent, that is, a hydrocarbon compound having 1 to 12 carbon atoms in which some or all of the hydrogen has been replaced with a halogen element, is used. For example, carbon tetrachloride, tetrachloroethane, chloroform, chlorobenzene, hexachlorobutane, etc. are used.

These solvents are used in an amount of 200 to 2000 parts by weight per 100 parts by weight of the ethylene polymer.

The dissolution of the polymer is carried out in an autoclave at a temperature of 50-150°C. Chlorosulfonation reaction uses chlorine and sulfur dioxide gas or chlorine and sulfuryl chloride to react to contain 10 to 60% chlorine and 0.5 to 4.0% sulfur, but chlorine and sulfuryl chloride are used relatively often. Regarding the reaction, 5 to 100 parts by weight of chlorine and 5 to 100 parts by weight of sulfuryl chloride are first added to the polymer solution.
Although the chlorination temperature can be the same as the melting temperature of the polymer, it is preferably 50 to 80°C when sulfuryl chloride is added. Thus, for example, chlorine is added at a temperature of 80-120°C until the chlorine content of the polymer is around 20%, and then sulfuryl chloride is added at a temperature of 50-80°C. While adding chlorine and sulfuryl chloride, an azo catalyst such as azobisisobutyronitrile is used as a catalyst per 100 parts by weight of the polymer.
It is dissolved in the halogen-containing organic solvent and added continuously in a proportion of 0.1 to 2 parts. When the chlorosulfonation reaches a predetermined value, the addition of the catalyst is stopped and the solution is boiled while blowing an inert gas, such as nitrogen or argon, into the reaction system to eliminate unreacted chlorine gas remaining in the system. and by-product hydrochloric acid.

In the manner described above, a halogen-containing organic solvent solution containing the raw material chlorosulfonated ethylene polymer is obtained. This raw material solution is then emulsified, so
Mixed with cationic surfactant.

As the cationic surfactant, higher amines such as polyoxyethylene tallow propylene diamine, tallow alkylamine, hardened tallow alkyl dimethylamine, higher alkyl amines, or acid salts thereof are used.

These surfactants are preferably used in an amount of 11 to 30 parts by weight per 100 parts by weight of the chlorosulfonated ethylene polymer.
Use 15-25 parts. If the amount of surfactant is less than the above range, the emulsification state will be poor, and powdering may not be possible, or the polymer may precipitate during recovery of the solvent. In addition, if there is a large amount, the obtained powdered rubber may become colored or
It becomes easier to block.

Emulsification is carried out by adding these surfactants to the polymer solution and mixing them, or by preparing an aqueous solution of the surfactants in advance and mixing this with the polymer solution.

For emulsification, use an emulsifying machine such as a homomixer or homosinizer that can rotate at high speed. The solvent can be recovered from this emulsified chlorosulfonated ethylene polymer by a conventional method. For example, this can be carried out by contacting with water vapor under reduced pressure or by using a rotary evaporator.

The thus obtained latex of chlorosulfonated ethylene polymer is then mixed dropwise into a mixed solution of a water-soluble anionic polymer compound solution and anionic diene polymer latex in order to co-powder it with a diene polymer. Ru.

The chlorosulfonated ethylene polymer contained in the latex will be described below as a chlorosulfonated ethylene polymer (A), and the diene polymer as a diene polymer (B).

As the water-soluble anionic polymer compound, sodium carboxymethyl cellulose, gum arabic, sodium alginate, cellulose acetate phthalate, etc. are used. 0.1 to 10 parts by weight, preferably 1 part by weight
~8 parts by weight is dissolved in 100 to 2000 parts by weight of water for use. If the amount of this anionic polymer compound is less than the above range, it will be difficult to separate the rubber powder, and if it is too much, the quality of the rubber will be degraded.

Next, as a diene polymer latex, chloroprene, butadiene, isoprene, etc. may be used alone or together with one or more comonomers such as styrene, acrylonitrile, methyl methacrylate, acrylic acid, 2,3 dichlorobutadiene, etc., and anionic The mixture is made by mixing one or more types of surfactants such as disproportionated rosin soap, sodium dodecylbenzene sulfonate, and sodium lauryl sulfate, using the mixture as an emulsion, and emulsion polymerizing it at a temperature of 0 to 70°C. used.

Next, this diene polymer latex is mixed in advance with the water-soluble anionic polymer compound aqueous solution in such an amount that the ratio of diene polymer (B) to chlorosulfonated ethylene polymer (A) becomes the desired ratio. be done.

The ratio of diene polymer (B) to chlorosulfonated ethylene polymer (A) can be set to any desired ratio, but practically it is about 95:5 to 10:90.

Co-powderization is carried out by dropping the chlorosulfonated ethylene polymer latex into this mixed solution at room temperature. After the mixing is completed and the polymer is separated into powder, the synthetic resin emulsion is subsequently added with gentle stirring. Addition of this synthetic resin emulsion allows the emulsion particles to be adsorbed onto the surface of the rubber particles and dehydrated and dried, thereby preventing adhesion between the rubber particles.

The synthetic resin emulsion may contain anionic or nonionic surfactants such as sodium lauryl sulfate, sodium dodecylbenzenesulfonate, nonyl lauryl sulfate, oleyl ether or nonyl ether of polyoxymethylene, polyoxyethylene alkyl esters, etc. alone or Mix and use as an aqueous emulsion,
Those obtained by emulsion polymerization of vinyl acetate, methyl methacrylate, styrene, vinyl chloride, etc. are used, and resins with a melting point of 100° C. or higher are preferred. This resin emulsion contains 0.5 to 20 parts by weight of resin, preferably 1 part by weight, per 100 parts by weight of the chlorosulfonated ethylene polymer (A) and diene polymer (B).
Use in an amount of ~10 parts by weight.

If the amount of synthetic resin is less than this range, the particle size of the obtained powdered rubber will be non-uniform, and if it is too much, the resin may precipitate alone or the properties of the obtained rubber may deteriorate. The obtained co-powdered product of chlorosulfonated ethylene polymer and diene polymer was centrifugally dehydrated and then
Dry with ventilation at a temperature of 70°C or less so that the volatile content is 1% by weight or less.

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited thereto.

Note that unless otherwise specified, "parts" indicate parts by weight, and "%" indicates weight %.

Example 1 (a) Preparation of a solution of a chlorosulfonated ethylene polymer in a halogen-containing organic solvent by a raw material solution method. branched polyethylene
Dissolve 1000 parts in 10000 parts of carbon tetrachloride at 120°C. Next, chlorine gas is introduced into the system at a rate of 1.5 per minute. At this time, as a catalyst, 2.0 parts of azobisisobutyronitrile dissolved in 200 parts of carbon tetrachloride was continuously added using a pump. Chlorination is 20
%, the temperature is lowered to 70° C. and 350 parts of sulfuryl chloride are then added in 1 hour.

The reaction begins when the chlorination reaches a predetermined value (approximately 4
After some time) The addition of catalyst and chlorine is stopped, and unreacted chlorine and by-product hydrogen chloride in the solution are removed by boiling while blowing nitrogen. As a result, 11,904 parts of a carbon tetrachloride solution containing 1,400 parts of chlorosulfonated ethylene polymer was obtained. The obtained chlorosulfonated ethylene polymer contains chlorine 30.4
It contained 1.4% sulfur.

(b) Preparation of aqueous latex of chlorosulfonated ethylene polymer Polyoxyethylene beef tallow propylene diamine (Naimeen DT-203 Japan) was added to 850 parts of carbon tetrachloride solution containing 100 parts of the chlorosulfonated ethylene polymer obtained in (a). (manufactured by Yushisha Co., Ltd.) and emulsify this with 1000 parts of water containing 6 parts of glacial acetic acid using a homomixer at room temperature.

Next, carbon tetrachloride was removed from the mixture under reduced pressure using a rotary evaporator at a temperature of 80°C to obtain 1000 parts of an aqueous latex containing 10% of the chlorosulfonated ethylene polymer.

(c) Preparation of diene polymer latex 1000 parts of chloroprene and 2.0 parts of n-dodecitamercaptan were mixed with 40 parts of disproportionated potassium rosinate, 4.0 parts of caustic soda, and 7 parts of a formaldehyde-sodium naphthalene sulfonate condensate with water.
1000 parts of the solution was mixed, and 1 g of potassium persulfate aqueous solution was continuously added at a temperature of 40°C to polymerize until the conversion rate was 70%. Unreacted monomers were removed, resulting in a chloroprene polymer containing 33.3%. latex
Obtained 1950 copies.

(d) Preparation of synthetic resin emulsion 100 parts of styrene and 4.0 parts of sodium lauryl sulfate
A solution of 200 parts of water dissolved in 200 parts of water was mixed in an autoclave purged with _N2 , 0.1 part of lauryl peroxide was added, and the mixture was heated at a temperature of 50°C for 8 hours.
Emulsion polymerization was carried out for a period of time, and unreacted styrene was distilled off using an evaporator under reduced pressure to obtain 285 parts of an emulsion containing 34% of styrene polymer.

Chlorosulfonated ethylene polymer obtained in (b)
800 parts of the latex containing 10% sodium carboxymethyl cellulose was added to a mixture of 500 parts of an aqueous solution containing 5 parts of sodium carboxymethylcellulose and 60 parts of the latex with a chloroprene polymer content of 33.3% obtained in (c) at room temperature while stirring. to separate the rubber particles.

Next, 12 parts of the emulsion with a styrene polymer content of 34% obtained in step (d) was added to this, mixed and stirred, and then dehydrated with a centrifuge and dried at a temperature of 70°C or less using a fluidized fluid dryer to reduce the volatile content to 1% or less. Dry until dry.

The obtained powdered rubber was 95 parts, and the weight ratio of chlorosulfonated ethylene polymer and chloroprene polymer was
The particle size was 83:17, and 95% of them had a particle size of 32 mesh or less.

Example 2 Using an ethylene polymer with a melt index of 5.0 obtained by a low-pressure process as a raw material, chlorosulfonation was performed in the same manner as in Example 1 to reduce the chlorine content.
A carbon tetrachloride solution containing 12.8% of chlorosulfonated ethylene polymer with a sulfur content of 35.0% and a sulfur content of 1.0% was obtained.

Then, 781 parts of this solution was emulsified in the same manner as in Example 1, and 917 parts of an aqueous latex (polymer content 10.9%) were used, except that 5 parts of sodium alginate was used as the anionic polymer compound. Powderization was performed in the same manner as in Example 1. The obtained powdered rubber was 97 parts, the weight ratio of chlorosulfonated ethylene polymer and chloroprene polymer was 80:20, and 92% of it had a particle size of 32 mesh or less.

Example 3 Using an ethylene vinyl acetate copolymer having a melt index of 7.0 and containing 5% vinyl acetate as a raw material, chlorosulfonation was performed in the same manner as in Example 1 to obtain chlorine with a chlorine content of 40.2% and a sulfur content of 0.8%. 11,643 parts of a carbon tetrachloride solution containing 1,658 parts of a sulfonated ethylene vinyl acetate copolymer was obtained.

Then the above solution 702.3 containing 100 parts of the polymer
Powdering was carried out in the same manner as in Example 1 using 820.5 parts (copolymer content: 9.75%) of an aqueous latex obtained by emulsifying 1 part in the same manner as in Example 1. As a result, 96 parts of powdered rubber having a weight ratio of chlorosulfonated ethylene vinyl acetate copolymer and chloroprene polymer of 81:19 was obtained. 90% of them had a particle size of 32 mesh or less.

Example 4 In place of the chloroprene polymer latex, 57.9 parts of a styrene-butadiene copolymer latex (containing 20 parts of polymer) prepared as described below was used.
98 parts of powdered rubber having a weight ratio of chlorosulfonated ethylene polymer and styrene-butadiene copolymer of 79:21 was obtained by carrying out the reaction treatment in the same manner as in Example 1, except for using chlorosulfonated ethylene polymer and styrene-butadiene copolymer. 91.5% of these had a particle size of 32 mesh or less. Styrene-butadiene copolymer latex was prepared by mixing 70 parts of butadiene in an autoclave with 30 parts of styrene and 0.10 parts of t-dodecylmercaptan, 1.3 parts of disproportionated potassium rosinate, 1.7 parts of potassium oleate, and a naphthalene sulfonic acid-formaldehyde condensate. Mix and stir a solution of 0.7 parts of sodium salt, 0.35 parts of potassium chloride, dissolved in 85 parts of water, and add 0.015 parts of ferrous sulfate and 0.025 parts of sodium ethylenediaminetetraacetic acid to 1 part of water at a temperature of 5°C. and a 1% aqueous solution of diisopropyl hydroperoxide were continuously added, and polymerization was carried out to a polymerization conversion rate of 56%. Unreacted monomers were then recovered and a styrene-butadiene copolymer containing 21.5% styrene was prepared with a content of 34.5%.
162 parts of latex were obtained.

Example 5 The same recipe as in Example 1 was used except that a vinyl chloride polymer emulsion prepared as described below was used instead of the styrene polymer emulsion, and chlorosulfonated ethylene polymer and chloroprene polymer 97 parts of powdered rubber with a combined weight ratio of 84:16 was obtained. Of these, 93.5% had a particle size of 32 mesh or less.

The vinyl chloride polymer emulsion was prepared by mixing and stirring 100 parts of vinyl chloride with a solution of 4.0 parts of sodium lauryl sulfate and 0.25 parts of sodium hydrogen phosphate in 180 parts of water in an autoclave purged with nitrogen, and then adding potassium persulfate to the solution. Aqueous solution containing 0.3 parts
Add 10 parts and react at 50℃ for 8 hours to form a polymer.
A vinyl chloride polymer emulsion containing 33% was obtained. (Polymerization degree of PVC: 1350) Example 6 The amount of chlorosulfonated ethylene polymer latex was 400 parts (polymer content 10%), and the amount of chloroprene polymer latex was 180 parts (polymer content 33.3%).
Powderization was carried out in the same manner as in Example 1 except for changing the formulation. The powdered rubber obtained was 95 parts;
The weight ratio of the chlorosulfonated ethylene polymer to the chloroprene polymer was 42:58, and 85% of them had a particle size of 32 mesh or less.

Claims (1)

[Scope of Claims] 1. A halogen-containing organic solvent solution of a chlorosulfonated ethylene polymer obtained by a chlorosulfonation reaction of an ethylene polymer by a solution method is aqueous emulsified with a cationic surfactant, and then the halogen-containing The latex of chlorosulfonated ethylene polymer (A) obtained by removing the organic solvent is mixed with the latex of anionic diene polymer (B) and these polymers (A) and (B).
and 0.1 to 10 parts by weight of a water-soluble anionic polymer compound per 100 parts by weight in total to form a co-powder of the chlorosulfonated ethylene polymer and the diene polymer, and then add it to the mixture. the polymer
A chlorosulfonated ethylene polymer and a diene polymer, which are prepared by adding an emulsion containing 0.5 to 20 parts by weight of a synthetic resin per 100 parts by weight of (A) and (B), followed by dehydration and drying. A method for producing powdered rubber consisting of. 2. The method for producing powdered rubber according to claim 1, wherein the ratio of the chlorosulfonated ethylene polymer (A) to the diene polymer (B) is 95:5 to 10:90.