DE1054715B - Process for the production of synthetic resins with anion-exchange properties - Google Patents

Description

GERMAN

It is known from German patents 829 223, 841 796 and 848 257, synthetic resins with anion exchangers To produce properties by converting haloalkyl into crosslinked polymers based on introduces vinyl aromatic compounds and reacts the reaction products obtained with amine. Will If ammonia is used to carry out this process in the second reaction stage, a considerable amount of this occurs Extensive side reactions with the formation of products with secondary or tertiary amino- ίο groups, so that it is not possible to use derivatives of said crosslinked polymers exclusively contain primary aminoalkyl groups.

In order to counter this difficulty, the haloalkylated ones mentioned have already been crosslinked Polymers reacted with potassium phthalimide to give the corresponding phthalimido compounds and then saponified these to give the corresponding aminoalkyl derivatives (British Patent 767,821).

This process thus requires three reaction steps to introduce the aminoalkyl groups, viz firstly the introduction of the haloalkyl groups, secondly the reaction with phthalimide potassium and thirdly, the saponification of the reaction products. It has now been found that synthetic resins with anion-exchanging Properties can be obtained in a much simpler manner if one uses crosslinked polymers based on vinylaromatic Compounds in the presence of Ouellungsmittel and Friedel-Crafts catalysts with a N- (haloalkyl) phthalimide condensed and the reaction products saponified.

It has also been shown that the synthetic resins obtained by the process have a significantly higher one Have anion exchange capacity than the products obtained by the known process. The reason this should be seen in the fact that the known processes in halomethylation give rise to additional cross-links through further reaction of the haloalkyl groups introduced with aromatic ones Give seeds. This apparently means that some of the chloroalkyl groups introduced go for the intended ones Amination lost, as it is also known that by haloalkylation of uncrosslinked polystyrenes, such as B. with chloromethyl ether and aluminum chloride, insoluble, d. H. networked products are created.

The introduction of aminoalkyl groups by means of chloromethylphthalmide in low molecular weight aromatic hydrocarbons, such as. B. benzene or naphthalene is a known reaction, but it was not to be expected from the outset that this reaction would be transferred to crosslinked polymers based on vinyl aromatic compounds and that this process would also be used for production
of synthetic resins with anion-exchanging properties

Applicant:

Paint factories Bayer Aktiengesellschaft, Leverkusen-Bayerwerk

Dr. Herbert Corte, Leverkusen,

and Dr. Otto Netz, Cologne,
have been named as inventors

Ways can produce anion exchangers, the capacity of which is significantly higher than that of the aforementioned known exchangers. While the capacity of the anion exchangers obtained by amination from the haloalkyl compounds by the previously known process is 1.3 to a maximum of 1.5 meq / cm ³ , the process according to the invention gives anion exchangers with capacities of 1.7 to 2 meq / cm ³ .

The crosslinked polymers used to carry out the present process based on vinyl aromatic compounds are known per se. Copolymers in particular are used for this purpose from a predominant proportion of monovinylaromatic! '' compounds, such as B. styrene, substituted styrenes, vinyl naphthalene and a minor proportion of aromatic or aliphatic Compounds with multiple vinyl groups, such as. B. divinylbenzene, substituted divinylbenzenes, Divinyl ketone and polyesters made from polyhydric alcohols and olefinically unsaturated carboxylic acids, such as B. ethylene glycol and dimethacrylate in question. These copolymers can have a gel structure as well as have a sponge structure. Such copolymers are z. B. in the German patents 829 223, 841796, 848 257 and in U.S. Patents 2,597,439, 2,597,440 'and in the German patent application F 22532 IVb / 39c (German Auslegeschrift 1 045 102).

_{For example, SnCl 4} and ZnCl ₂ can be used as Friedel-Crafts catalysts.

Suitable swelling agents are e.g. halogenated hydrocarbons such as ethylene chloride and perchlorethylene.

The reaction of the copolymers mentioned with the N- (haloalkyl) -phthalimides can be

805 789/533

For example, take place in such a way that the components mentioned in the presence of a swelling agent and a Friedel-Crafts Kathalysators at elevated temperature, preferably at the boiling point of the Swelling agent, are reacted until the formation of hydrogen halide has ended. The phthalimides are preferably at least in molar amounts, calculated on the basis of the copolymer existing aromatic nuclei.

For saponification of the phthalimidoalkyl compounds formed as intermediates can the known methods, such as. B. alkaline or acidic hydrolysis, sales with hydrazine and subsequent acid hydrolysis in the presence or absence of solution or Ouelling agents are used.

The aminoalkyl compounds prepared according to the invention can furthermore be modified by alkylation. Known agents, such as, for. B. chloromethyl, dimethyl sulfate, ethylene oxide, ethylene imine. The completely insoluble amino compounds can also be alkylated in aqueous suspension, that is to say without the use of a solvent. When using z. B. alkyl halides or dialkyl sulfates, the amount of an alkaline agent such as NaOH, CaCO ₃ , MgO required to neutralize the hydrohalic acids or alkyl sulfuric acids formed must be added. The alkylations are carried out at temperatures below 150.degree. C., preferably below 100.degree.

In this way, strongly basic exchangers can be obtained, which also have a significantly higher capacity than the known anion exchangers, which are crosslinked by amination of haloalkyl derivatives Polystyrenes e.g. B. arise with trimethylamine.

example 1

624 g of styrene, 76 g of divinylbenzene (55%, remainder ethyl styrene) and 5 g of benzoyl peroxide are ^{suspended with stirring in 1200 cm 3 of} water containing 0.1% methyl cellulose, and with stirring for 8 hours at 65 to 70 ° C and then heated to 90 ° C. for 2 hours. After cooling below 50.degree. C., the bead polymer formed is filtered off with suction, washed several times with water and dried at 100 to 110.degree. C. in vacuo.

100 g of the bead polymer are swollen into a solution of 30 g of tin tetrachloride in 300 cm ^{3 of ethylene chloride.} The mixture is then heated to the boil and 200 g of N- (chloromethyl) phthalimide are added in small portions over the course of 4 hours. The mixture is refluxed until the evolution of hydrochloric acid ceases (about 6 hours) and then cooled to below 30.degree. The reaction liquid is suctioned off, whereupon the beads are washed twice with ethylene chloride and tetrahydrofuran and sucked dry. The beads are then ^{refluxed with 300 cm 3 of} water, 16 g of caustic soda and 64 g of hydrazine hydrate for 6 hours, again filtered off with suction, washed with water and then refluxed with 500 cm ^{3 of} 10% hydrochloric acid for 6 hours, with phthalhydrazide separating out is washed out with dilute sodium hydroxide solution. After treatment with excess 5% hydrochloric acid and then water, 460 cm ^{3 of} an anion exchanger (crosslinked polyaminomethylstyrene hydrochloride) with an HCl binding capacity of 1.98 g equivalents per liter of hydrochloride are obtained.

To transfer it to a strongly basic anion exchanger, 460 cm ^{3 of} the hydrochloride are ^{suspended in 1500 cm 3 of} 10% NaOH and treated with chloromethane under a pressure of 1 atm to saturation at 40 to 45 ° C. with stirring. After suctioning off the reaction solution and washing with 5% hydrochloric acid and water, 500 cm ^{3 of} the chloride form of a strongly basic anion exchanger with an anion exchange capacity of 1.82 g equivalents per liter of chloride form are obtained.

Example 2

ίο 624 g styrene, 76 g divinylbenzene (55%, remainder ethyl styrene), 490 g white spirit (b.p. 160 to 196 ° C) and 5 g benzoyl peroxide are mixed and ^{poured into 1200 cm 8 of} water containing 0.1% methyl cellulose, suspended with stirring. The suspension is heated to 65 to 70 ° C. for 8 hours and then to 90 ° C. for 2 hours and then cooled to 50 ° C., with constant stirring. The bead polymer formed with a sponge structure is filtered off with suction, washed several times with water and in vacuo at 100 to 110.degree

ao dried. 100 g of this bead polymer are heated to the boil together with 30 g of freshly dehydrated zinc chloride and 300 cm ^{3 of ethylene chloride.} 200 g of N- (chloromethyl) phthalamide are added in small portions to the boiling mixture over a period of about 3 to 5 hours and the mixture is boiled until the development of hydrochloric acid has ceased. After cooling below 30 ° C., the reaction liquid is suctioned off. The remaining beads are washed twice with ethylene chloride and then with dioxane. Then the dry-sucked pearls are ^{heated together with 800 cm 3 of} 14% sodium hydroxide solution at 170 to 180 ° C. for 10 hours. After cooling, the reaction liquid is filtered off with suction and the beads are washed several times with water and then with dilute hydrochloric acid. 450 cm ^{3 of} crosslinked polyaminomethylstyrene hydrochloride with an HCl binding capacity of 1.91 g equivalents per liter of hydrochloride are obtained; the product is opaque and has a sponge structure. Treatment of the weakly basic anion exchanger thus obtained with chloromethane using the method described in Example 1 gives 490 cm ^{3 of} a strongly basic anion exchanger with a sponge structure, which has an anion exchange capacity of 1.73 g equivalents per liter of chloride form.

Example 3

300 g are added to a solution of 1635 g of N- (chloromethyl) phthalimide in 2000 ml of ethylene chloride of the polystyrene resin according to Example 1 swollen and 50 ml of conc. Sulfuric acid added. The mixture is heated to boiling under reflux until the evolution of HCl gas has ended. The condensate is washed with ethylene chloride and then twice with methanol and split off of the phthalic acid residue with 3000 ml of 12% hydrazine hydrate solution and 600 ml of 45% sodium hydroxide solution Heated for 12 hours to 95 to 100 ° C, suction filtered and then with 2200 ml of 10% hydrochloric acid Heated to 95 ° C for 6 hours. The resin is filtered off with suction and washed with dilute sodium hydroxide solution. After treatment with excess 5% hydrochloric acid, 1400 ml of a weakly basic anion exchanger are obtained with an HCl binding capacity of 2.0 g equivalents per liter of hydrochloride.

Example 4

1150 g of N- (oxymethyl) -phthalimide are with

2750 ml conc. Hydrochloric acid stirred for 2 hours at 50 to 55 ° C, during which N- (chloromethyl) phthalimide finely

granularly deposited. The slurry is stirred with 1300 ml of ethylene chloride at 50 ° C until everything has clearly dissolved and two easily separable layers are created when it is allowed to sit down. After separating the ethylene chloride-chloromethylphthalimide solution is distilled until the boiling point is im The descending cooler has reached 84 ° C and the last traces of moisture have distilled over azeotropically are.

250 g of the polystyrene resin according to Example 1 are swollen into the solution, which has been cooled to 50.degree and then added 50 g of tin tetrachloride as a catalyst. The mixture will, last under Reflux, heated until the evolution of HCl gas is finished. The reaction product is filtered off with suction, with ethylene chloride and then twice washed with methanol.

To split off the phthalic acid residue, the reaction product is mixed with 1400 ml of 24% hydrazine hydrate solution and 360 ml of 45% sodium hydroxide solution for 12 hours at 90 to 95 ° C, then with 1100 ml 20% hydrochloric acid heated to 95 to 100 ° C for 6 hours. The resulting anion exchange resin is Sucked off, washed with water and dilute sodium hydroxide solution and neutralized with dilute hydrochloric acid. 1325 ml of a weakly basic exchanger with an HCl binding capacity of 2.5 g equivalents per liter of hydrochloride.

Example 5

1500 ml of the weakly basic exchange resin according to Example 3 of 1.9 g equivalents per liter are converted into the OH form and then heated with 600 ml of 40 percent by volume formaldehyde solution and 600 ml of 90% formic acid, finally under reflux, until the _{evolution of CO 2} gas has ended. It is filtered off with suction, washed with water, dilute sodium hydroxide solution and water again and treated with excess dilute hydrochloric acid. 1600 ml of a weakly basic exchange resin containing tertiary amino groups and an HCl binding capacity of 1.75 g equivalents per liter of hydrochloride are obtained.

The resin is then converted into the OH form with dilute sodium hydroxide solution and heated to 50 to 60 ° C. for 18 hours with 500 ml of water, 500 ml of ethylene chlorohydrin (2-chloroethanol) and 140 ml of 45% sodium hydroxide solution. After suctioning off and washing, 1625 ml of a strongly basic anion exchange resin with a capacity of 1.73 g equivalents per liter of hydrochloride are obtained.
5

Example 6

1060 ml of the anion exchange resin containing primary amino groups according to Example 3 are mixed with 250 ml of water, 450 ml of formaldehyde solution (40 percent by volume), 70 ml of conc. Sulfuric acid and 250 ml of formic acid (90%), finally under reflux, heated until the _{evolution of CO 2} gas has ceased. It is filtered off with suction, washed with sodium hydroxide solution and water and neutralized with dilute hydrochloric acid.

Yield 1140 ml of an anion exchange with tertiary amino groups and an HCl binding capacity of 1.9 g equivalents per liter of hydrochloride.

750 ml of the aforementioned exchange resin in the OH form are _{concentrated with 300 ml of H 2} O and 25 ml. H ₂ SO ⁴ added. A stream of ethylene oxide is passed through the mixture at 30.degree. After 120 g of ethylene oxide have been taken up, the gas flow is interrupted, the resin is suctioned off and washed with water. 1345 ml of a strongly basic exchange resin were produced with a capacity of 1.6 g equivalents per liter of hydrochloride.

Claims (2)

Patent claims: 1. Process for the production of synthetic resins with anion-exchanging properties, thereby characterized in that crosslinked polymers based on vinyl aromatic compounds in the presence of swelling agents and Friedel-Crafts catalysts with an N- (haloalkyl) phthalimide condensed and the reaction products obtained are saponified. 2. The method according to claim 1, characterized in that the reaction products obtained be alkylated. Considered publications:
German patents No. 829 223, 841 796,
848 247; British Patent No. 767 821.