DE1155603B - Process for the production of cation exchange resins containing sulfonic acid groups - Google Patents

Description

It is known that ion exchange resins containing sulfonic acid groups can be prepared by using copolymers from one or more monovinyl aromatics and one or more polyfunctional ones vinyl group-containing crosslinkers by means of, for example, sulfuric acid, oleum, chlorosulfonic acid, liquid Sulfur trioxide or mixtures of the same sulfonated and thus strong in such copolymers introduces acidic groups which are capable of ion exchange, in particular of neutral salt cleavage. In general, a bead-shaped polystyrene crosslinked with divinylbenzene is used as the starting polymer for such a cation exchange resin for use. However, these polymers show the Disadvantage that after sulfonation and work-up to the corresponding cation exchange resins the mechanical resistance of the latter for essential purposes of their technical use is still insufficient.

For example, when the sulfonated copolymers still contain sulfonating agents are introduced into water, the resin matrix is extremely stressed by the heat of dilution released by the sulfonating agent and by strong osmotic swelling effects, so that the individual spherical ion exchange resin particles have cracks and some of them disintegrate. However, sufficient mechanical resistance is an essential prerequisite for the technical use of these products. In order to suppress the above-mentioned grain breakdown, it is known that the sulfonated copolymers, after the excess sulfonating agent has been separated off, not directly with water, but with concentrated electrolyte solutions, e.g. B. sodium sulfate solution, sulfuric acid, caustic soda, etc. to treat and then gradually dilute the latter. It is also known that the destruction of the cation exchange resin grains can be reduced by pre-swelling the styrene-divinylbenzene copolymer in solvents such as dichloroethane, dichloromethane, perchlorethylene and the like and only subsequently sulfonating it. In spite of all this, the occurring grain disintegration is still considerable, especially if the grain size is above about 0.5 mm in diameter. It is also known to use certain purification methods in order to free the styrene copolymers used for sulfonation from low molecular weight impurities. Such cleaning methods are, for example, extraction, among others. These measures can also improve the strength of the cation exchange resin resulting from the copolymer. The mentioned metho-process for the production
of cation exchange resins containing sulfonic acid groups

Applicant:

VEB paint factory Wolfen,
Wolfen (district of Bitterfeld)

Dr. Reinhard Bachmann, Engelsdorf near Leipzig,

Dipl.-Chem. Ulrich Krauss, Halle / Saale,
Dipl.-Chem. Gerhard Schwachula, Leipzig,

Dr. Dieter Warnecke, Greppin,

Dr. Wilhelm Wehlend, Halle / Saale,

and Dr. Friedrich Wolf, Leipzig,

have been named as inventors

but the general disadvantage of the ^ polymer after-treatment is that the product before the Sulphonation must be freed again from, for example, excess solvent. aside from that do not lead to the desired copolymer aftertreatment methods in all cases The aim is to obtain a sufficiently stable cation exchange resin, even the extreme one Strength requirements are sufficient.

It is therefore a technical advance to find a method that allows the named cumbersome and time-consuming treatment methods for the initial copolymer or to circumvent the sulfonated copolymer and, moreover, in any case a mechanically extraordinary one To obtain stable cation exchange resin, which is essential in its strength properties shows better values than the previously known products.

It has now been found that cation exchange resins containing sulfonic acid groups can be obtained from copolymers one or more monovinyl aromatics and one or more polyvinyl carbons of particular strength, hardness and mechanical resistance, if 0.001 to 0.2 mol of vinyl group-containing polar compounds

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bonds per mole of monovinyl aromatic with polymerized and the copolymers obtained are sulfonated by known agents.

As monovinyl aromatics, styrene, vinyl toluene, vinyl ethylbenzene, vinyl anisole and others can be used. Divinylbenzene, divinylethylbenzene, can be used as crosslinking polyvinyl hydrocarbons. Trivinyl benzene, divinylacetylene, butadiene, divinyl ketone and others. Polar compounds containing vinyl groups, which have both ion exchange active and ion exchange inactive polar moieties are, according to the invention, for example acrylic acid and its derivatives, methacrylic acid and their derivatives, in particular nitriles, such as acrylonitrile or methacrylonitrile, methyl vinyl ketone and homologues, Vinyl halides, vinyl benzyl halides, methyl vinyl ethers and homologues, vinyl sulfonic acid and its derivatives, styrene sulfonic acid and its derivatives, vinyl pyridine and homologues, esters of vinyl alcohols, such as vinyl acetate, vinyl propionate, maleic acid and their derivatives, among others. The crosslinking polyvinyl hydrocarbons generally reach in amounts of 0.01 to 0.2 mol per mole of monovinyl aromatic Mission. It should be emphasized in this connection that the mentioned polar ion exchange active or ion exchange inactive vinyl group-containing compounds both water-soluble and water-insoluble can be to the products described also by the method of bead polymerization to manufacture. Measures which form free radicals are used in a known manner to initiate the polymerization applied, e.g. high-energy radiation, thermal treatment, addition of radical-generating Compounds such as dibenzoyl peroxide, azo-bisisobutyric acid nitrile, dilauroyl peroxide, diacetyl peroxide, tert. Butyl perbenzoate et al.

The resins produced according to the invention are characterized by an unusually high strength and hardness and mechanical stability, which is characterized among other things by the fact that the sulfonated copolymers Washed off immediately with water after the excess sulfonating agent had been separated off without affecting the mechanical stability of the individual spherical cation exchange resin particles in the slightest is affected. In addition, it is a special feature of the copolymers prepared according to the invention, that the sulfonation without pre-swelling with solvents such. B. dichloroethane, dichloromethane and others, can be carried out and yet not the hardness and stability of the sulfonated resin particles sinks. It is a further characteristic of the cation exchange resins produced according to the invention, that the ion exchange capacity is above all the neutral salt splitting capacity compared to resins, which are based exclusively on vinyl aromatics and polyvinyl hydrocarbons, nothing Experience reduction. The individual ion exchange particles are crystal clear pearls without any Crack or crack. They have about ten times the strength of the previously known ones Process produced copolymers containing sulfonic acid groups and capable of cation exchange. The hardness, strength and mechanical resistance of ion exchange resins can be compared with conventional Determine methods where the resin z. B. mechanically stressed in a ball mill will.

The examples demonstrate the practice of the invention. Examples are included for comparison purposes without the addition of polar compounds containing vinyl groups with specified, z. B .:

Example 1:

without additive with pre-swelling,

Example 2:

without addition without pre-swelling; against it:

Example 3:

with additive with pre-swelling,

Example 4:

with additive without pre-swelling.

Precisely from these comparative examples, the results obtained by adding the vinyl group-containing the strength improvement brought about by polar compounds.

example 1

A mixture of 120 g of styrene and 30 g of divinylbenzene (50%) is, after the addition of 0.5 g of dibenzoyl peroxide as a polymerization initiator, in an aqueous phase, consisting of 750 cm ^{3 of} water and 50 cm ^{3 of} a 3% aqueous magnesium silicate suspension, distributed and heated with stirring for 4 hours at 7O ⁰ C and then for 8 hours 90 ° C. The resulting bead-like polymer is filtered off with suction, washed with water and air-dried.

50 g of the copolymer are swollen in 25 g of dichloroethane and then ^{treated with 200 cm 3 of} sulfuric acid monohydrate at 100 ° C. for 5 hours. After the excess sulfonating agent has been suctioned off, the resin is introduced into saturated sodium sulfate solution and then washed out with water. The cation exchange resin shows an ion exchange capacity of 5.08 meq per gram of dry substance and an abrasion of 54%. An experiment carried out in parallel, in which the sulfonated copolymer was worked up directly with water, shows an abrasion of 91%. The abrasion determination as a test method for the strength and mechanical resistance of the resins is carried out as follows:

100 cm ^{3 of} a resin fraction of 0.5 to 1 mm diameter are rolled ^{for 1} hour in a ball mill (15 cm diameter, 15 cm height) with 150 porcelain balls (11 mm diameter) at 100 rpm. The grain fraction below 0.5 mm in diameter is determined and reported as abrasion.

Example 2

50 g of the copolymer prepared according to Example 1 are 300 cm ^:! Treated sulfuric acid monohydrate for 5 hours at 100 ° C. After working up according to Example 1, a cation exchange resin is obtained with an ion exchange capacity of 4.88 meq per gram of dry substance and an abrasion of 94 or 100% when washed directly with water.

Example 3

A mixture of 115 g of styrene, 30 g of divinylbenzene (50%) and 5 g of methyl methacrylate is added to an aqueous phase consisting of 750 cm ^{3 of} water and 0.5 g of dibenzoyl peroxide

50 cm ³ of a 3 ¹ Aigen aqueous magnesium silicate suspension, distributed and heated with stirring for 4 hours at 70 ° C, then 8 hours to 90 ° C. The resulting bead polymer is filtered off with suction, washed with water and air-dried.

50 g of the copolymer are swollen in 25 g of dichloroethane and then treated with 300 cm ^{: i} sulfuric acid monohydrate for 5 hours at 100 ° C.

per gram of dry substance and an abrasion of 1.1 ⁰ Zt-

An experiment carried out in parallel, the work-up taking place directly with water, shows one 5 abrasion of 2.3 «Ό.

Example 7 50 g of the copolymer prepared according to Example 6

acts. After working up in accordance with Biosats, with 300 cm ^:! a mixture of 2 parts by weight of 20% strength oleum and 1 part by weight of chlorosulfonic acid at 95 ° C. for 3 hours. After the excess sulfonant has been spun off, the product is washed out with water. The cation exchange resin shows an ion exchange capacity of 5.18 meq per gram of dry substance and an abrasion of 8.3%. 50 g of the copolymer prepared according to Example 3

sats are mixed with 300 cm ^{3 of} sulfuric acid monohydrate Example 8

Treated for 5 hours at 100 ° C. After the work-up ao device according to Example 1 is a cation exchange resin with an ion exchange capacity of

Game 1 results in an exchanger with an ion exchange capacity of 5.11 meq per gram of dry matter and an abrasion of 5.6 resp. 6.2 ° / c for direct washing with water.

Example 4

5.06 meq per gram of dry matter and an abrasion of 8.3 or 9.8% in direct washing obtained with water.

A mixture of 250 g of styrene, 20 g of divinylbenzene (50%) and 15 g of metharyl acid is, after the addition of 1 g of dilauroyl peroxide, distributed in a solution of 1.5 g of methyl cellulose in 1500 cm ^{3 of} water and heated to 95 ° for 10 hours with stirring C heated. The polymer obtained is washed with water and dried at 100 ° C. for 1 hour.

50 g of the copolymer are in a mixture of 200 g of dichloromethane and 150 g of liquid sulfur

Example 5

A mixture of 50 g styrene, 7 g divinylbenzene
(62.5 ° / cig) and 1.5 g of methyl vinyl ketone is suspended in an aqueous 30 feltrioxyd after the addition of 0.3 g of dibenzoyl peroxide and boiled for 4 hours under the reflux phase consisting of 500 cm ^{3 of} water and 50 cm ³ . After the excess of a 3% aqueous magnesium silicate suspension, swelling and sulfonating agent, the product is distributed and ^{heated to 70 ° C and 250 cm 3 of} methanol for 4 hours and then with water for 8 hours to 90 ° C. That dewashed. The resulting bead-like polymer formed by a cation exchange is filtered off with suction, the resin has an ion exchange capacity of 5.07 meq, washed with water and dried in the air. per gram of dry matter and an abrasion of

50 g of the copolymer are dissolved in 25 g of dichloro 10.2%. swollen with ethane and then ^{treated with 200 cm 3 of} sulfuric acid monohydrate for 4 hours at 100 ° C. After working up as in Example 1, an exchanger with an ionic

Example 9

A mixture of 250 g of styrene, 30 g of divinylbenzene (50%) and 8 g of maleic anhydride is, after the addition of 0.5 g of dibenzoyl peroxide, distributed in a solution of 1.5 g of methyl cellulose in 1500 cm ^{3 of} water and stirred for 9 hours 95 ° C heated. The polymer obtained is washed with water and dried at 70 ° C. for 2 hours. 50 g of the copolymer are swollen in 35 g of dichloroethane and then ^{treated with 300 cm 3 of} sulfuric acid monohydrate at 105 ° C. for 5 hours. After suction

0.5 g of azo-bis-isobutyronitrile in an aqueous 50% of the excess sulfonating agent, the product phase consisting of a suspension of 15 g is washed out with water. The cation exchanger hydroxylapatite in 1000 cm ^{3 of} water, distributed and
with stirring for 2 hours to 65 ° C, 2 hours
75 ° C, 2 hours at 85 ° C and 6 hours at 95 ° C
heated. The resulting bead-shaped polymer 55
is suctioned off, washed with water and 2 hours
dried at 80 ° C.

50 g of the copolymer are swollen in 25 g of dichloromethane and then with 300 cm ^:!

exchange capacity of 5.1 meq per gram of dry substance and an abrasion of 3.4% or of 4.1% for direct washing with water.

Example 6

A mixture of 250 g of styrene, 35 g of divinylbenzene (62.5 ° / cig) and 1 g of acrylonitrile is after the addition of

Resin shows an ion exchange capacity of 5.13 meq per gram of dry substance and an abrasion of

2.8 »/ 0.

Example 10

A mixture of 250 g of styrene, 50 g of divinylbenzene (50%) and 20 g of propyl styrenesulfonate is used after adding 0.3 g of azo-bis-isobutyric acid nitrile in

a mixture of 2 parts by weight 20 ° / cigem 60 of a solution of 1.5 g methyl cellulose in 1500 cm ^{: i}

Treated oleum and 1 part by weight of chlorosulfonic acid at 95 ⁰ C for 3 hours. After the excess sulphonating agent has been spun off, the resin is introduced into 80% sulfuric acid after V4 hours

Distributed water and heated to 80 ° C and 6 hours at 95 ° C with stirring for 2 hours. The polymer is washed and air-dried. 50 g of the copolymer are mixed with 250 cm ^{3 of} chlorine

suctioned off, introduced into 50% sulfuric acid, treated with sulfonic acid at 100 ° C. for 3 hours. According to ^l / 4 hours again filtered off with suction and then washed the centrifuging of the excess sulfonating agent with water. The cation exchange resin shows an ion exchange capacity of 5.26 meq

is washed out with water. The cation exchange resin shows an ion exchange capacity of

5.21 meq per gram of dry matter and one 7.9% abrasion.

Example 11

After adding 1 g of dibenzoyl peroxide, a mixture of 250 g of styrene, 50 g of divinylbenzene (50%) and 5 g of ethyl acrylate is distributed in an aqueous phase consisting of 1500 cm ^{3 of} water and 100 cm ^{3 of} a 3% aqueous magnesium silicate suspension and heated to 75 ° C. for 6 hours and then to 95 ° C. for 6 hours with stirring. The resulting bead-like polymer is washed and dried at 80 ° C. for 2 hours. 50 g of the copolymer are swollen in 20 g of dichloromethane and then ^{treated with 250 cm 3 of} sulfuric acid monohydrate at 95 ° C. for 4 hours. After the excess sulfonating agent has been suctioned off, the resin is introduced into saturated sodium sulfate solution and then washed out with water. The cation exchange resin shows an ion exchange capacity of 5.23 meq per gram of dry substance and an abrasion of 1.2%.

Example 12

A mixture of 500 g of styrene, 50 g of divinylbenzene (38%) and 30 g of vinyl sulfonic acid is after addition of 2.5 g of diacetyl peroxide as a polymerization initiator in an aqueous phase consisting of 2500 cm ^{s of} water and 200 cm ^{3 of} a 3% aqueous Magnesium silicate suspension, distributed and heated to 98 ° C. for 5 hours with stirring. The resulting bead-shaped polymer is washed and air-dried.

50 g of the copolymer are swollen in 15 g of trichlorethylene and then ^{treated with 200 cm 3 of} 10% strength oleum at 100 ° C. for 3 hours. After working up as in Example 11, a cation exchange resin results with an ion exchange capacity of 5.06 meq per gram of dry substance and an abrasion of 6.9%.

Example 13

A mixture of 500 g of styrene, 50 g of divinylbenzene (38%) and 10 g of 4-vinylpyridine is, after the addition of 0.5 g of azo-bis-isobutyronitrile, distributed in a solution of 4 g of methyl cellulose in 2500 cm ^{s of} water and while stirring Heated to 98 ° C for 7 hours. The resulting bead-shaped polymer is washed and air-dried.

50 g of the copolymer are swollen in 15 g of trichlorethylene and then ^{treated with 200 cm 3 of} 20% strength oleum at 95 ° C. for 3 hours. After working up according to Example 11, an ion exchanger results with an ion exchange capacity of 5.04 meq per gram of dry substance and an abrasion of 4.1%.

Example 14

15 g of gaseous vinyl chloride are passed into a mixture of 250 g of styrene and 20 g of divinylbenzene (50%). After adding 0.3 g of azo-bis-isobutyronitrile, the liquid is distributed in a 5% strength aqueous magnesium hydroxide suspension and heated to 70 ° C. for 3 hours and to 98 ° C. for 5 hours with stirring under normal pressure. The resulting bead-like polymer is filtered off with suction, washed with water and air-dried. 50 g of the copolymer are swollen in 25 g of dichloroethane and then ^{treated with 200 cm 3 of} sulfuric acid monohydrate at 100 ° C. for 4 hours. After working up as in Example 1, the result is an exchanger with an ion exchange capacity of 5.1 meq per gram of dry substance and an abrasion of 8.2%.

Claims (2)

PATENT CLAIMS: 1. A process for the preparation of cation exchange resins containing sulfonic acid groups from copolymers of one or more monovinyl aromatic compounds and one or more polyvinyl hydrocarbons, characterized in that 0.001 to 0.2 mol of vinyl group-containing polar compounds per mole of monovinyl aromatic compounds are polymerized and the copolymers obtained are sulfonated by known agents. 2. The method according to claim 1, characterized in that polyvinyl hydrocarbons in Amounts of from 0.01 to 0.2 moles per mole of monovinyl aromatic can be used. Considered publications: U.S. Patent No. 2,678,306. © 309 727/328 10.63