NO129001B - - Google Patents

Description

Procedure for the production of silver or

carbon-containing polymers or copolymers.

The invention relates to the production of new complex metal compounds in which monovalent solvate or copper ions together with a polymer's nitrile groups form complex cations which are at least partially bound by means of ionic bonds to strongly acidic groups in the same polymer or a neighboring macromolecule.

So far, only chelates of solvate or copper ions with poly-

more known, as the chelates contain iminodiacetic acid groups (so-called IDE resins, see e.g. Dr. Habil. Rudolf Hering, Chelate-bildende Ionenaustauscher^ Akademie-Verlag Berlin 1967, pp. 91-93). Otherwise, the existence of complex cations of monovalent copper with nitrile groups could only be deduced from the fact that acrylic fibers (polyacryl-nitrile fibers) can be dyed with acid wool dyes in the presence of a

valuable copper ions. In this case, the theoretical explanation of which was long lacking, however, a number of complex ions -CN.Cu are formed only on the fiber surface to which the acid dye molecules are bound by ion binding. Polymeric complex compounds where not only the nitrile groups, but also the strongly acidic groups are bound on a macro-molecular skeleton, have not been described so far.

The present method is characterized by the fact that polymeric systems

which, in addition to strongly acidic groups, such as sulfo groups, contain nitrile groups in the polymer skeleton, are brought into contact with solutions containing monovalent solyions and/or monovalent copper ions so that the amount of bound metal based on dry polymer is 10-50% by weight.

For easily understandable reasons, primarily aqueous solutions are used, but the mentioned metal ions can, however, also be collected from non-aqueous solutions.

The formation of the complex compounds occurs very quickly, especially if the polymer or the copolymer is swollen beforehand.

Copolymers of acrylonitrile or methacrylonitrile with ethylenesulfonic acid or styrenesulfonic acid are particularly suitable as poly-

more or copolymers with strongly acidic groups and nitrile groups. In addition to these main components, they may also contain other components

parts, such as acryl- or metha er yl amide,' acryl- or methacryl-

acid or esters thereof, vinylpyrrolidone etc. Of strongly acidic groups -SO^H and -OSO^H should be mentioned first and foremost.-

If, instead of copolymers, a mixture of homopolymers is used, one of which contains nitrile groups and the other strongly acidic groups, similar results can be obtained. dissolve-

ning of or solid mixtures of such homopolymers are combined or made insoluble by the influence of Ag - or Cu - respectively. Ct^

ions, and the polymeric complex metal compounds thus obtained then have better mechanical and other properties than the original polymer mixtures.

They thus formed inter- and intramolecular ionic bonds

acts as an ionic cross-link which, in contrast to the covalent cross-link, allows an orientation upon stretching. This relationship is of particular importance due to the fact that the relevant polymers or copolymers swell strongly in water, whereby their firmness is be-

considerably reduced. In the dry state, these polymers and copolymers are usually too brittle to enable stretching without breaking. The metal ions can optionally be removed later by means of stronger complexing agents or other means, whereby the original polymer is again obtained, albeit in an oriented state. Thereby, for example, ion-exchange membranes can be produced, whose firmness and space resistance when changing the ion concentration have been significantly improved. Sulfur-containing, polymeric complex compounds produced according to the present invention are also sensitive to light and can be used within

for photography - respectively the reproduction technique either directly or after being transferred to other derivatives.

The new metal-containing polymers can also be used in the production of special coatings, e.g. as a topcoat when painting ships etc. The silver or copper ions that are slowly released from the complex compound, and the complex compounds themselves, are toxic to various organisms and thereby prevent the growth of unwanted organisms.

The tendency to form polymeric complex compounds

is particularly strong for solar ions, so it is possible to use polymeric systems which, in addition to nitrile groups, also contain strongly acidic groups, such as sulfo groups, to capture solar ions from different, even highly diluted, solutions. The solvent ions are thereby taken up quantitatively.

Finally, the polymeric complex compounds produced according to the invention can also be used as special filter material, e.g.

in the form of membranes or threads. In this form or also as grains with different shapes, they can also be used as catalysts,

as an aging agent for alcoholic beverages or as an ion exchange.

If strongly acidic groups, such as sulfo groups, are numerically superior in the polymeric system used, the solv or copper complex compound forms a cation exchanger. If, on the other hand, the nitrile groups occur more frequently, the cations -CN.Ag will be the dominant ones, and the complex polymer will then act as an anion exchanger which can quantitatively capture free, strong acids, especially organic ones such as e.g.

acid dyes for wool, or other organic sulphonic acids. The exchange capacity is of course dependent on the number of free acidic or basic groups.

Membranes of the scnlv- or copper-containing polymers produced according to the invention are also suitable for filtering aqueous solutions of high-molecular, non-penetrating compounds without, however, clogging the intermolecular pathways for water molecules and small ions. If there is no possibility of clogging pores, the metal-containing polymers can also be produced in a clearly porous or macroporous state. It is then sufficient, for example, when producing a membrane for the copolymer solution and for evaporation of the solvent mixture to add a highly volatile liquid which does not dissolve the copolymer. For the evaporation, good solvents, such as dimethylformamide, prevent the formation of a precipitate, but with progressive evaporation, however, the solubility of the copolymer becomes increasingly lower, and a macroporous structure is formed. A porous structure can be easily obtained if the copolymer solution is not completely dried in a good solvent, such as e.g. dimethylformamide-water, and the still rather soft membranes are washed with an excess of water. Solvent or monovalent copper ions are then allowed to act on the porous or non-porous membranes produced in this way.

The starting polymers swell strongly in water and in aqueous solutions and also in various polar solvents, such as methanol, dimethylformamide, etc. With a higher content of strongly acidic groups, the copolymers are water-soluble, in the same way as polyethylenesulphonic acid and polystyrenesulphonic acid. Unbranched, but water-insoluble, copolymers are soluble in solvent mixtures, such as e.g. dimethylformamide-water or dimethylsulfoxide-water-methanol. The swelling ability in water decreases with decreasing content of strongly acidic groups.

The metal is relatively strongly bound in the polymeric complex compound, and the solvate allows e.g. do not remove from this with 20% nitric acid. Silver is more strongly bonded than copper. 23% ammonia-water does not split the sdlv complex, but the copper complex. Here, of course, the metal's reactivity towards the reagent also plays an important role.

With. strong i"educs ionic agents, both metals can be washed out

from the polymeric complex compounds and can then be dissolved as so-

form in known reagents. Thus, metallic sol can be dissolved in nitric acid and copper in hydrochloric acid.

Under the influence of halogen ions, soluble sblv halides are formed from the sblv complex compounds, and the sblv halides are distributed as a fine precipitate in the polymers or the copolymers. The grain size of the sulfur halides can be made larger by longer standing in the swollen state, possibly at an elevated temperature or in the presence of peptizing agents, such as e.g. ammonia, whereby the sensitivity to light becomes greater in a known manner. As the above-mentioned copolymers, e.g. of acrylonitrile with ethylenesulfonic acid, are very similar to naturally occurring or hardened gelatins, light-sensitive layers can be produced in this way on paper, glass or film substrates.

Membranes or threads can, for example, be produced by a solution, e.g. in water or in a mixture of dimethylformamide and water, is pressed out in a coagulating bath containing monovalent solv or copper ions. After coagulation and possibly after washing out, the threads or membranes can be oriented by stretching.

If a layer of a copolymer with a predominant number of nitrile groups is deposited on a dried layer of a copolymer with a predominant number of strongly acidic groups, after evaporation of the solvent and the effect of monovalent silver or copper ions, a bipolar membrane is obtained if both halves are firmly connected by intermolecular ionic bonds. Such membranes can be used for various electrochemical purposes.

The membranes according to the invention can, for example, also be used for dialysis and electrodialysis, for fuel elements etc.

Example. 1

2 moles of acrylonitrile and 1 mole of sodium ethylene sulfonate in a 50% aqueous solution were mixed, and a concentrated aqueous zinc chloride solution with a specific gravity of 1.95 was added until both components were dissolved. A redox initiator of 0.1% potassium pyrosulfite and 0.1% ammonium persulfate in the form of 5% solutions in water, and 0.0001% copper sulfate pentahydrate was then incorporated and the slightly cloudy solution was polymerized under carbon dioxide. The next day, the viscous solution was added as a thin stream and under stirring to an excess of 0.2% hydrochloric acid. The thread-shaped, highly swollen smear was washed several times in 0.5% nitric acid and in distilled water. By filtration, as much of the water as possible was removed, and dimethylformamide was poured over the highly swollen copolymer in water in an amount of approx. 3 times the volume of the copolymer, and the copolymer was dissolved under stirring and heating in the dimethylformamide. Gases were-under vacuum removed from the filtered, approx. 5$ resolution, and the resolution was then poured to a height of 2mm on a precisely horizontal, ground glass plate. After slow evaporation of the solvent

the agent at a moderate temperature, a clear hard layer was formed which, after swelling in water, could be removed without difficulty. After repeated washing with 0.5% nitric acid, water, 1% solution of the disodium salt of ethylenediaminetetraacetic acid and then again with water, the membrane was placed in a 0.2% sodium nitrate solution. The membrane soon shrunk and became opaque and whitish gray. After washing out the excess sodium nitrate, the membrane could e.g. used for ultrafiltration.

It could be easily oriented when stretched, and its firmness was thereby considerably improved. The membrane remained in an oriented state after removing the dust with a sodium thiosulphate solution (photographic fixer bath) and washing out in water. The difference between the largest and smallest linear swelling in pure water and in 0.1 ln nitric acid was approx. 20-40$ depending on the degree of orientation, while on the other hand the differences obtained by carrying out a parallel experiment with part of the same, but non-oriented membrane, were 150-215$.

Example 2

A loop of a 0.8 mm wire was placed between two glass plates,

and the fixed plates were closed on three sides by immersing the edges of the plates in a melted mixture of beeswax and stearin. After removing the wire loop, a flat stick shape was obtained with an exact inside width of 0.8 mm. The mold was filled with a monomer mixture consisting of 10 ml of a 50% aqueous sodium ethylene sulfate solution, 4 ml of acrylonitrile, 1

drop of ethylene glycol-bis-methacrylate and 8 ml of concentrated, aqueous zinc chloride solution with a specific gravity of 1.98". Just before filling, the solution was initiated with 5 drops of each of two solutions of potassium pyrosulphite and ammonium persulphate with a concentration of 5$. Any gas bubbles present were removed by

knocking on the glass plates because the viscosity had started to rise. The filled mold was allowed to stand in a vertical position at a temperature of 15°C. The gel formation point was reached after approx. 20 minutes, and after 3 hours the copolymerization was complete. The wax layer on the edges of the mold was cut open with a sharp knife, and the mold was carefully opened under water. The copolymer film thus obtained, which was initially very soft due to the zinc chloride solution, was alternately washed with 0.5% nitric acid, water, 5% citric acid and again with water. The film was finally placed in a 5% sodium chloride solution in water and washed thoroughly with water after 30 minutes. The membrane had similar properties to the membrane according to example 1, but it was less stretchable and more elastic. When stretched, it could only be partially oriented, which is due to the partial cross-linking with glycol-bis-methacrylate.

Example 3

Powdered metallic copper in an amount of approx. 5 wt$ was added to a 10$ aqueous solution of copper sulfate pentahydrate. The copper had been produced in the usual way by precipitation with iron during boiling and washing with pre-boiled water. 10% by weight of hydroxylamine sulfate was then added. In the thus prepared solution containing monovalent copper ions, a copolymer membrane was prepared according to example 2 infor. After 3 hours the membrane became considerably stiffer and firmer than due to the influence of the monovalent copper ions. The membrane also shrunk noticeably in a similar way as when exposed to the sodium nitrate solution. The membrane was colored slightly grey, and the coloring was not weakened by prolonged washing with water. The properties of the membrane were similar to the properties of the membrane according to example 2.

Example 4

IN

Water-soluble acrylonitrile-ethylene sulfonic acid copolymer was prepared as follows: , 57.5 g of a 47% aqueous, neutral solution of ethylene sulfonic acid! sodium stabilized with 0.2$ sodium nitrite, was added 3 g ; urea and acidified with concentrated hydrochloric acid to a pH of ; 2. After thorough removal of gas under vacuum, 7.1 g of acrylamide and 13.6 ml of acrylonitrile were added. To this mixture, under a carbon dioxide atmosphere, 76 ml of oxygen-free water was added until all '; solids had gone into solution. Then 1 ml of a 5% potassium pyrosulfite solution and the same amount of an ammonium persulfate solution of the same concentration were added, and the slightly cloudy solution was allowed to stand for 24 hours under carbon dioxide at room temperature, a copolymer solution thus prepared whose viscosity had decreased noticeably , was poured in the form of a thin jet into an excess of anhydrous ethanol during stirring. The white, soft copolymer that adhered to the converter was transferred to new, anhydrous ethanol and allowed to remain in this for 12 hours. The copolymer was then broken up into small pieces and dried at 70°C. After dissolution in distilled water and filtration, the copolymer was again precipitated in anhydrous ethanol. A 20% viscous solution of the copolymer was poured onto a horizontal glass plate and slowly dried. 27% formalin, which had been acidified with 0.2% hydrochloric acid, was poured over the broken layer, and the whole was then allowed to stand for 2 hours. The formaldehyde solution was then washed out with; water, and the membrane

which had been made water-insoluble by the cross-linking between the amide groups of the acrylamide units, could be easily removed from the glass. The membrane was divided into 2 halves. One was, without further ado, placed in water as a control sample while the other was placed in a 5% sodium nitrate solution for 5 minutes and then washed with water. With this treatment, the sample became opaque. It shrunk considerably and gained a several times higher tear strength.

Example 5

A 5% solution of polyacrylonitrile with an average molecular weight of 32,000 in dimethylformamide was precipitated with a 5% solution of the sblv salt. The blue salt solution had been prepared by splitting a solution of the free polyethylene sulfonic acid with an n-3 blue nitrate solution. Polyethylene sulfonic acid was prepared by passing an aqueous solution of the sodium polyethylene sulfonate through a column with a strongly acidic cation exchanger. The precipitate consisting of a polymeric salt of the polyethylene sulfonic acid with the complex polyacrylonitrile sblv base, formed in the wet state a soft, white-gray, plastic mass which could be molded in this state. After a complete use, the mass could be oriented. In the dry state, the mass was sprbd and could be ground into a powder

which could possibly be hot-pressed after the addition of binders or plasticizers.

IN

Example 6

An 8$ solution was prepared by dissolving dried, powdered polyacrylonitrile in concentrated nitric acid at 10-15°G. The concentrated sodium salt of polyethylenesulfonic acid was dissolved in concentrated nitric acid. To the 10% solution, an equivalent of sodium nitrate in the form of a n solution was added. When mixing both clear polymer solutions, a white precipitate formed which, after washing with water, had the same properties as the product according to example 5.

Example 7

The membrane according to example 1 was, after treatment with sodium nitrate and washing, immersed in a 5% ammoniacal hydrazine sulphate solution. The membrane became black due to excreted metallic solv. It was then treated for a further 1 hour with a 1% sodium chloride solution and thoroughly washed with water. The membrane could be used for filtering water while simultaneously disinfecting or aging spirits. Without a subsequent treatment with sulfur nitrate, the oligodynamic effect is low, as the nitrile and sulfo groups released by the excretion of metallic silver again absorb all the sulfur ions.

Example 8

The solution of the copolymer according to example 1 in aqueous dimethylformamide was thickened to a concentration of 11%, filtered, degassed and through a spinning nozzle with 0.2 mm wide openings pressed into a spinning bath where a 5% concentration of sodium nitrate was obtained.- The threads was thoroughly washed with hot, distilled water, stretched and cut into staples. Metallic sol was separated by reduction as indicated in Example 7, and the staple fibers were treated with a sol nitrate solution and then washed. They were very suitable for filtering alcoholic beverages while simultaneously artificially aging them.

Example 9

The procedure according to example 6 was repeated, except that polyethylene sulphonic acid was replaced with polystyrene sulphonic acid. It was necessary to carry out a good cooling of the polystyrene sulphonic acid solution in concentrated nitric acid and a rapid processing of this to prevent too strong nitration. After washing out the nitric acid, the white-grey precipitate had similar properties to the precipitate according to example 6.

Example 10

A 10% solution of polyacrylonitrile with an average molecular weight of 55,000 in concentrated cold nitric acid was prepared at a temperature below 20°C. The solution was mixed with a likewise 10% solution of the sodium salt of polyethylene sulfone-; acid in concentrated nitric acid. The album stayed clear. Then a n-sulfonyl nitrate solution was added to the mixed polymer solution. A white precipitate was immediately formed which in daylight had a violet color and which, in addition to nitrogen, also contained

sulfur in the form of sulfonic acid groups.

Example. 1 11

A beaker with a slightly flat edge was tightly covered with a 0.5 mm thick membrane of regenerated cellulose and, in an upside-down state, immersed with this membrane (partition wall) in a dish containing a solution of an acrylonitrile-ethylene sulfonic acid copolymer with a molar ratio between the monomers of 2.5:1 in aqueous dimethylformamide.

Penetrating solar ions had precipitated the copolymer and formed a porous membrane. The nature of the membrane could be changed within wide limits by changing the sodium nitrate concentration, the permeability of the partition wall and the quality of the copolymer, respectively. concentration.

Example 12

The copolymer solution prepared according to example 1 in aqueous dimethylformamide was thickened to a concentration of 11% and spread in even, thin layers onto a cardboard paper and dried. The paper was then, under the exclusion of light, treated for 10 minutes with a 5% aqueous sodium nitrate solution and thoroughly washed. After printing, the paper was exposed to daylight for 5 minutes under a negative, and the image was developed in a methol-hydroquinone developer and fixed in the usual way. The image had a violet-brown colour.

Example 13

The paper according to example 12, after treatment with blue nitrate and washing, was treated with a 0.ln potassium bromide solution which also contained 1% potassium chloride and 0.1% potassium iodide. The paper was then, with the exclusion of light, treated for 1 hour at 30°C in a weak , aqueous soda solution at a pH of 8, washed well and dried. The paper had a higher sensitivity to light than the paper according to example 12.

Example 14

The procedure according to Example 13 was repeated, except that a more swellable copolymer with 7% sulfur was used, and the solution was also mixed with 5% gelatin, based on the fiber content, in the form of a solution in warm water. The layer's sensitivity to light was thereby considerably increased.

Example 15

The membrane produced according to example 1, which did not contain any metal, was cut into small pieces and filled into a small container. A highly diluted blue nitrate solution, which consisted of wash water from the preparation of the fibers according to Example 8, was slowly passed through this column. What happened was. quantitatively captured.

Claims (1)

Procedure for the production of sol- or copper-containing. polymers or copolymers, characterized in that polymeric systems which, in addition to strongly acidic groups, such as sulfo groups, contain nitrile groups in the polymer skeleton, are brought into contact with solutions containing monovalent solar ions and/or monovalent copper ions so that the amount of bound metal, based on dry polymer , becomes 10-50 weight#.