Process for the preparation of amidomethylated vinyl aromatic polymers

Abstract

The invention relates to a process for the preparation of amidomethylated vinyl aromatic polymers.

Description

[0001] P001 01254 Abroad

[0002] - 1 -

[0003] Method for the production of amidomethylated, vinylaromatic polymers

[0004] The invention relates to a process for the production of amidomethylated, vinylaromatic polymers.

[0005] WO-A 2024132644 discloses a process in which the amidomethylation of a vinylaromatic polymer is carried out with phthalimide, paraformaldehyde, and a protic acid in the presence of liquid sulfur dioxide in a one-pot process. A disadvantage of this process is that a high proportion of the amidomethylated vinylaromatic polymers undergo structural degradation during the conversion to the aminomethylated vinylaromatic polymer.

[0006] Therefore, there was a need for a process that overcomes the disadvantages of the state of the art and with which aminomethylated vinylaromatic polymers can be produced in good yields and with high stability.

[0007] It has now been surprisingly found that the reaction of vinylaromatic polymers with N-hydroxymethylimides and protic acids in the presence of sulfur dioxide leads to amidomethylated vinylaromatic polymers, which can be reacted to form aminomethylated vinylaromatic polymers without significant decomposition of the polymers.

[0008] The present invention therefore relates to a process for the production of amidomethylated, vinylaromatic polymers in which at least one vinylaromatic polymer is combined with at least one compound of formula (I) or its salts. where R 1 = -C(H(Ci-C6-Alkyl))- or -CH2- and R 2 = -C(H(Ci-C6-Alkyl))- or -CH2- or R1 and R 2 are two carbon atoms of an aromatic C6 ring, optionally substituted by one or two Ci-C6 alkyl groups, or R 1 and R 2 Each stands for -CH=, P001 01254 Abroad

[0009] - 2 - is reacted in the presence of at least one protic acid and in the presence of sulfur dioxide.

[0010] R 1 and R 2 preferably together form an aromatic C6 ring, optionally substituted by a Ci-Ce alkyl. R particularly preferably 1 and R 2The vicinal residue of a benzene ring, which is optionally substituted by Ci-C4 alkyl, is particularly preferred. Compounds of formula (I) N-hydroxymethylphthalimide, N-hydroxymethylsuccinimide, or N-hydroxymethylmaleimide are especially preferred. Compound of formula (I) N-hydroxymethylphthalimide is even more preferred. When using N-hydroxymethylphthalimide, phthalimidomethylated polymers are produced according to the invention. Salts of the compounds of formula (I) are preferably addition products of inorganic or organic bases with compounds of formula (I), such as, preferably, ammonium salts and alkali or alkaline earth metal salts. If salts are used, the sodium and potassium salts of the compounds of formula (I) are particularly preferred.

[0011] Within the scope of the invention, Ci-C6-alkyl and Ci-C4-alkyl represent a straight-chain, branched, or cyclic alkyl group with 1 to 6 or 1 to 4 carbon atoms, respectively. By way of example, and preferably, Ci-C6-alkyl represents methyl, ethyl, n-propyl, isopropyl, n-, i-, s-, or t-butyl, cyclopropyl, and 1-methylbutyl.

[0012] Ci-C4-Alkyl is used as an example and preferably represents Methyl, Ethyl, n-Propyl and Isopropyl.

[0013] The reaction is preferably carried out in the presence of liquid sulfur dioxide. However, mixtures of sulfur dioxide and other swelling agents can also be used.

[0014] Sulfur dioxide acts as a swelling agent for the polymers and also serves as a solvent for the other reactants of the amidomethylation reaction. Other organic swelling agents can also be added to the amidomethylation reaction. These include, for example, and preferably, benzotrifluoride, dibromomethane, 1,2-dichloroethane, 1,2-dichloropropane, 1,3-dichloropropane, 1,4-dichlorobutane, 1,6-dichlorohexane, methylene chloride, carbon tetrachloride, trichloroethane, chlorobenzene, 1,2-dichlorobenzene, carbon dioxide, or nitro-substituted hydrocarbons such as nitropropane, nitrobenzene, or cyclic hydrocarbons such as cyclohexane and methylcyclohexane. Preferably, no other swelling agents or solvents are used. P001 01254 Abroad

[0015] - 3 -

[0016] Preferably, the amount of sulfur dioxide in the swelling agents used is 80 to 100 wt.%. Particularly preferred is the amount of sulfur dioxide in the swelling agents used, which is 90 to 100 wt.%. Most particularly preferred is the amount of sulfur dioxide in the swelling agents used, which is 98 to 100 wt.%.

[0017] Protic acids can be, for example, inorganic or organic. Examples of inorganic protic acids include hydrochloric acid, sulfuric acid, oleum, nitric acid, nitrous acid, sulfurous acid, aliphatic or aromatic methanesulfonic, benzenesulfonic, or toluenesulfonic acids, or phosphoric acid. Examples of organic protic acids include oxalic acid, acetic acid, or formic acid. Inorganic protic acids are preferred. Sulfuric acid or oleum are particularly preferred as protic acids.

[0018] The polymers produced according to the invention are preferably spherical. The polymers preferably have a diameter of 200 to 1000 pm. Spherical polymers are referred to as pearl polymers.

[0019] The term vinylaromatic as used in the invention includes polyvinylaromatic and monovinylaromatic monomers. For the production of the vinylaromatic polymers, at least one monovinylaromatic compound and at least one polyvinylaromatic compound are used, for example. However, it is also possible to use mixtures of two or more monovinylaromatic compounds and mixtures of two or more polyvinylaromatic compounds. Preferably, at least one monovinylaromatic compound and at least one polyvinylaromatic compound are used to produce the vinylaromatic polymers.

[0020] Styrene, vinyltoluene, ethylstyrene, α-methylstyrene, chlorostyrene and chloromethylstyrene are preferably used as monovinylaromatic compounds in accordance with the present invention.

[0021] Styrene or mixtures of styrene with the aforementioned monomers are particularly preferred.

[0022] The monovinyl aromatic compounds are preferably used in amounts greater than or equal to 80 wt.%, more preferably from 80 to 99 wt.% based on the weight of monomers. P001 01254 Abroad

[0023] - 4 -

[0024] Preferred polyvinylaromatic compounds according to the present invention are divinylbenzene, divinyltoluene, trivinylbenzene, triallyl isocyanurate, divinylnaphthalene or trivinylnaphthalene.

[0025] The polyvinyl aromatic compounds are preferably used in amounts of 1 to 20 wt.%, particularly preferably in amounts of 2 to 12 wt.%, and most preferably 4 to 10 wt.%, based on the weight of the monomers. The type of polyvinyl aromatic compound (crosslinker) is selected with regard to the subsequent use of the polymer. Divinylbenzene is suitable in many cases. For most applications, commercially available grades of divinylbenzene, which contain ethylvinylbenzene in addition to the isomers of divinylbenzene, are sufficient.

[0026] In a preferred embodiment, the vinylaromatic polymers are styrene-divinylbenzene cross-linked copolymers.

[0027] In a preferred embodiment of the present invention, microencapsulated monomer droplets are used.

[0028] Materials suitable for microencapsulation of the monomer droplets are those known for use as complex coacervas, in particular polyesters, natural and synthetic polyamides, polyurethanes, and polyureas.

[0029] Gelatin, for example, is particularly well-suited as a natural polyamide. It is especially used as a coacervate and complex coacervate. Gelatin-containing complex coacervases, as defined in the invention, are primarily combinations of gelatin with synthetic polyelectrolytes. Suitable synthetic polyelectrolytes are copolymers with incorporated units of, for example, maleic acid, acrylic acid, methacrylic acid, acrylamide, and methacrylamide. Acrylic acid and acrylamide are particularly preferred. Gelatin-containing capsules can be hardened with conventional hardening agents such as formaldehyde or glutaraldehyde. The encapsulation of monomer droplets with gelatin, gelatin-containing coacervas, and gelatin-containing complex coacervas is described in detail in EP-AO 046 535. The methods for encapsulation with synthetic polymers are known.For example, interfacial condensation is well suited, in which a reactive component dissolved in the monomer droplet, such as an isocyanate or an acid chloride, is reacted with a second reactive component dissolved in the aqueous phase, such as an amine. P001 01254 Abroad.

[0030] - 5 -

[0031] The optionally microencapsulated monomer droplets may contain an initiator or mixtures of initiators to trigger the polymerization. Initiators suitable for the process according to the invention are preferably peroxy compounds such as dibenzoyl peroxide, dilauroyl peroxide, bis(p-chlorobenzoyl) peroxide, dicyclohexyl peroxydicarbonate, tert-butyl peroctoate, tert-butyl peroxy-2-ethylhexanoate, 2,5-bis(2-ethylhexanoyl peroxy)-2,5-dimethylhexane, or tert-amyl peroxy-2-ethylhexane, as well as azo compounds such as 2,2'-azo-bis(isobutyronitrile) or 2,2'-azobis(2-methylisobutyronitrile). Dibenzoyl peroxide is particularly preferred.

[0032] The initiators are preferably used in amounts of 0.05 to 2.5 wt.%, particularly preferably in amounts of 0.1 to 1.5 wt.%, based on the monomer mixture.

[0033] As further additives in the optionally microencapsulated monomer droplets, porogens can optionally be used to create a macroporous structure in the polymer. Organic solvents that poorly dissolve or swell the resulting polymer are suitable for this purpose. Hexane, dextane, isooctane, isododecane, methyl ethyl ketone, butanol, or octanol and their isomers are preferably mentioned. Isododecane is particularly preferred as a porogen. Porogens are preferably used in the production of the amidomethylated, vinylaromatic polymers according to the invention.

[0034] The terms microporous or gel-like or macroporous have already been described in detail in the specialist literature.

[0035] Preferred polymers according to the present invention have a macroporous structure.

[0036] Macroporous within the meaning of the invention preferably means that the mean diameter of the pores in the polymer is > 25 nm. Particularly preferably, the pores in the polymer of the macroporous polymers have a mean diameter of 30 nm to 1000 nm. Most preferably, the pores in the polymer of the macroporous polymers have a mean diameter of 30 nm to 100 nm.

[0037] Gel-like within the meaning of the invention means that the BET surface area is < 2 m² 2 / g. Preferably, the BET surface area is 0.02 m² for gel-like polymers. 2 / g up to 2 m 2 / G.

[0038] Preferably, the BET surface area is > 20 m² for macroporous polymers. 2 / g. P001 01254 Abroad

[0039] - 6 -

[0040] The optionally microencapsulated monomer droplet may optionally contain up to 30 wt% (based on the monomer) of crosslinked or uncrosslinked polymer. Preferred polymers are derived from the aforementioned monomers, particularly preferably from styrene.

[0041] Polymers can be produced in heterodisperse or monodisperse form. Heterodisperse polymers are produced using general methods known to those skilled in the art, e.g., by suspension polymerization.

[0042] Preferably, monodisperse, vinylaromatic polymers are produced using the process according to the invention.

[0043] In the present application, substances are referred to as monodisperse if at least 90% by volume or mass, preferably 90% by volume, of the particles have a diameter that lies within the interval with a width of + / - 10% of the most frequent diameter around the most frequent diameter.

[0044] For example, for a fabric with a most common diameter of 0.5 mm, at least 90% by volume or mass lies within a size interval between 0.45 mm and 0.55 mm; for a fabric with a most common diameter of 0.7 mm, at least 90% by volume or mass lies within a size interval between 0.77 mm and 0.63 mm.

[0045] The monodisperse polymer can be prepared according to methods known from the literature. In the preparation of monodisperse, vinylaromatic polymers, the aqueous phase may optionally contain a dissolved polymerization inhibitor. Preferably, the aqueous phase contains a dissolved polymerization inhibitor. Both inorganic and organic substances are suitable as inhibitors within the meaning of the present invention. Examples of inorganic inhibitors are nitrogen compounds such as hydroxylamine, hydrazine, sodium nitrite, and potassium nitrite; salts of phosphorous acid such as sodium hydrogen phosphite; and sulfur-containing compounds such as sodium dithionite, sodium thiosulfate, sodium sulfite, sodium bisulfite, sodium thiocyanate, and ammonium thiocyanate. Examples of organic inhibitors are phenolic compounds such as hydroquinone, hydroquinone monomethyl ether, resorcinol, catechol, and tert-100.-Butyl catechol, pyrogallol, and condensation products of phenols with aldehydes. Other suitable organic inhibitors are nitrogen-containing compounds. These include hydroxylamine derivatives such as N,N-diethylhydroxylamine, N-isopropylhydroxylamine, as well as sulfonated or carboxylated N-alkylhydroxylamine or N,N-dialkylhydroxylamine derivatives, hydrazine derivatives such as N,N-hydrazinodiacetic acid, and nitroso compounds such as P001 01254 Ausland.

[0046] - 7 - for example, N-nitrosophenylhydroxylamine, N-nitrosophenylhydroxylamine ammonium salt, or N-nitrosophenylhydroxylamine aluminum salt. The concentration of the inhibitor is preferably 5 to 1000 ppm based on the aqueous phase, particularly preferably 10 to 500 ppm, and even more preferably 10 to 250 ppm. Resorcinol is preferably used as the polymerization inhibitor. A polymerization inhibitor is preferably used.

[0047] The polymerization of the optionally microencapsulated monomer droplets to form the monodisperse, vinylaromatic polymer is carried out, as already mentioned above, optionally in the presence of one or more protective colloids in the aqueous phase. Suitable protective colloids include natural or synthetic water-soluble polymers, such as gelatin, starch, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid, polymethacrylic acid, or copolymers of (meth)acrylic acid and (meth)acrylic acid esters. Cellulose derivatives, in particular cellulose esters and cellulose ethers, such as carboxymethylcellulose, methyl hydroxyethylcellulose, methylhydroxypropylcellulose, and hydroxyethylcellulose, are also very suitable. Gelatin is particularly well-suited and is preferably used. The amount of protective colloids used is preferably 0.05 to 1 wt% based on the aqueous phase, and particularly preferably 0.05 to 0.5 wt%.

[0048] The polymerization to the monodisperse, vinylaromatic polymer can optionally be carried out in the presence of a buffer system. Buffer systems that adjust the pH of the aqueous phase at the start of the polymerization to a value between 14 and 6, preferably between 13 and 8, are preferred. Under these conditions, protective colloids with carboxylic acid groups exist wholly or partially as salts. This favorably influences the effectiveness of the protective colloids. Particularly suitable buffer systems contain phosphate or borate salts. For the purposes of this invention, the terms phosphate and borate also include the condensation products of the ortho forms of the corresponding acids and salts. The concentration of the phosphate or borate in the aqueous phase is preferably 0.5 to 500 mmol / l, and particularly preferably 2.5 to 100 mmol / l.

[0049] The stirring speed during polymerization is less critical and does not affect particle size. Low stirring speeds are used, sufficient to keep the suspended monomer droplets in suspension and to facilitate the removal of the heat of polymerization. Various stirrer types can be used for this purpose. Axial-acting grid stirrers are particularly suitable. P001 01254 Abroad

[0050] - 8 -

[0051] The volume ratio of encapsulated monomer droplets to aqueous phase is preferably 1 :0.75 to 1 :20, particularly preferably 1 :1 to 1 :6.

[0052] The polymerization temperature depends on the decomposition temperature of the initiator used. It is preferably between 50 and 180°C, and particularly preferably between 55 and 130°C. The polymerization preferably lasts from 0.5 to several hours. It has proven advantageous to use a temperature program in which the polymerization is started at a low temperature, for example 60°C, and the reaction temperature is increased as the polymerization progresses. In this way, for example, the requirement for a reliable reaction and high polymerization conversion can be very well met. After polymerization, the polymer is isolated using conventional methods, preferably by filtration or decantation, and optionally washed.

[0053] The vinylaromatic polymer is reacted with at least one compound of formula (I) in the presence of sulfur dioxide and in the presence of at least one protic acid to form the amidomethylated vinylaromatic polymer.

[0054] The vinylaromatic polymer can, for example, first be swollen, perhaps in the presence of swelling agents other than sulfur dioxide, and in this state mixed with a mixture of the compounds of formula (I), the sulfur dioxide, and the protic acids. Alternatively, the compounds of formula (I) could first be added to the cross-linked polymer in the presence of sulfur dioxide, followed by the addition of the protic acids. Or, one could first prepare the compounds of formula (I) and the vinylaromatic polymer, add the sulfur dioxide, and then add the protic acid.

[0055] In a preferred embodiment of the invention, the vinylaromatic polymer and the compounds of formula (I) are first provided. Then, the sulfur dioxide, preferably in liquid form, is added. Preferably, the addition is carried out by pumping the sulfur dioxide into the reactor. The pressure is preferably increased, and the sulfur dioxide is converted back into liquid form. Then, preferably, the temperature is increased. Then, preferably, the protic acid is added. The separation of the sulfur dioxide is preferably carried out by reducing the pressure, preferably to atmospheric pressure. Preferably, the separated sulfur dioxide is collected in a further container and can then be reused. P001 01254 Abroad

[0056] - 9 -

[0057] Preferably, the reaction mixture is heated. The reaction is preferably carried out without separating any intermediate products formed from the reaction solution. The work-up of the reaction products is carried out according to a method known to those skilled in the art.

[0058] Preferably, the weight ratio of sulfur dioxide to the vinylaromatic polymer is 15:1 to 2:1. Particularly preferably, the weight ratio of sulfur dioxide to the vinylaromatic polymer is 12:1 to 3:1.

[0059] The stoichiometric ratio of the aromatic groups in the vinylaromatic polymer to the compounds of formula (I) is preferably 0.2:1 to 2.5:1. Particularly preferably, the stoichiometric ratio of the aromatic groups in the vinylaromatic polymer to the compounds of formula (I) is 0.5:1 to 1.8:1. Most preferably, the stoichiometric ratio of the aromatic groups in the vinylaromatic polymer to the compounds of formula (I) is 0.7:1 to 1.6:1.

[0060] The stoichiometric ratio of the compounds of formula (I) to the protic acid used is preferably between 10:1 and 1:10. Particularly preferably, the stoichiometric ratio of the compounds of formula (I) to the protic acid used is 1:1 to 1:10. Even more preferably, the stoichiometric ratio of the compounds of formula (I) to the protic acid used is 1:1 to 1:3.

[0061] If sulfuric acid is used as the protic acid, then the concentration of the sulfuric acid used is preferably 70 to 100 wt.%. Even more preferably, the concentration of the sulfuric acid used is 90 to 100 wt.%.

[0062] The reaction temperature for the conversion of the vinylaromatic polymers to the amidomethylated vinylaromatic polymers is preferably 0°C to 130°C. The reaction is preferably carried out at a pressure and temperature at which the solvents are liquid. If the reaction is carried out in the presence of sulfur dioxide, the pressure is preferably 4 to 20 bar. The reaction temperature is preferably 30°C to 90°C.

[0063] The amidomethylated vinylaromatic polymers are particularly important intermediates for the production of ion exchangers and chelating resins. For example, ion exchangers, especially anion exchangers, and chelating resins can be produced from the amidomethylated vinylaromatic polymers prepared according to the inventive process. P001 01254 Abroad

[0064] - 10 -

[0065] Preferably, the amidomethylated vinylaromatic polymer is converted in a further step to aminomethylated vinylaromatic polymers. From these, ion exchangers and chelating resins can then be produced using known methods.

[0066] The reaction is preferably carried out with at least one alkali or alkaline earth metal hydroxide or mixtures of these compounds, particularly preferably with alkali metal hydroxides such as sodium hydroxide or potassium hydroxide, or mixtures of these compounds. The reaction is particularly preferably carried out in the presence of an aqueous or alcoholic solution of an alkali metal hydroxide. The concentration of the alkali or alkaline earth metal hydroxide, preferably sodium hydroxide solution, is in the range of 10 to 60 wt.%, preferably 10 to 40 wt.%. The reaction to form the aminomethylated, vinylaromatic polymer is preferably carried out at temperatures of 100°C to 250°C, particularly preferably at temperatures of 120°C to 190°C.In a further preferred embodiment of the invention, the amidomethylated vinylaromatic polymer is heated in the presence of one or more alkali or alkaline earth metal hydroxides for a period of 6 to 10 hours at temperatures of 100°C to 250°C.

[0067] Another embodiment of the invention is a process for the production of aminomethylated vinylaromatic polymers, in which in a first step a.) at least one vinylaromatic polymer is combined with at least one compound of the formula

[0068] (I) or their salts where R 1 = -C(H(Ci-C6-Alkyl))- or -CH2- and R 2 = -C(H(Ci-C6-Alkyl))- or -CH2- or R 1 and R 2 are two carbon atoms of an aromatic C6 ring, optionally substituted by one or two Ci-C6 alkyl groups, or R 1 and R 2Each stands for -CH=, is reacted in the presence of at least one protic acid and in the presence of sulfur dioxide to form an amidomethylated, vinylaromatic polymer and P001 01254 Abroad

[0069] - 11 - in step b.) the amidomethylated vinylaromatic polymer from step a.) is reacted with at least one alkali or alkaline earth metal hydroxide and in the presence of water at a temperature of 100°C to 250°C.

[0070] The resulting aminomethylated, vinylaromatic polymer can be washed alkali-free with fully demineralized water.

[0071] The aminomethylated, vinylaromatic polymer can be reacted with further alkylating agents to form anion exchangers or chelating resins, or can be used as an ion exchanger.

[0072] Furthermore, it is possible to react the aminomethylated, vinylaromatic polymers according to the invention with halomethyl nitrogen heterocycles, such as 2-chloromethylpyridine, 3-chloromethylpyridine or 4-chloromethylpyridine, and thereby produce chelate resins.

[0073] The present invention provides a new manufacturing process for amidomethylated vinylaromatic polymers, with which these, in particular phthalimidomethylated polymers and aminomethylated polymers, can be produced in high yield and with high stability, taking ecological aspects into account.

[0074] P001 01254 Abroad

[0075] - 12 -

[0076] 1

[0077] 1.1 Production of the monodisperse, macroporous polymer based on styrene, divinylbenzene and ethylstyrene

[0078] In a 10-liter glass reactor, 3000 g of fully demineralized water are placed, and a solution of 10 g gelatin, 16 g disodium hydrogen phosphate dodecahydrate, and 0.73 g resorcinol in 320 g deionized water is added and mixed. The mixture is then heated to 25°C. While stirring, a mixture of 3200 g of microencapsulated monomer droplets with a narrow particle size distribution of 3.6 wt% divinylbenzene and 0.9 wt% ethylstyrene (used as a commercially available isomer mixture of divinylbenzene and ethylstyrene with 80% divinylbenzene), 0.5 wt% dibenzoyl peroxide, 56.2 wt% styrene and 38.8 wt% isododecane (technical isomer mixture with a high proportion of pentamethylheptane), wherein the microcapsule consists of a formaldehyde-cured complex coacervate of gelatin and a copolymer of acrylamide and acrylic acid, and 3200 g of aqueous phase with a pH of 12 is added.

[0079] The mixture is polymerized by gradually increasing the temperature under stirring, following a temperature program starting at 25°C and ending at 95°C. The mixture is then cooled, washed through a 32 pm sieve, and subsequently dried under vacuum at 80°C.

[0080] One obtains 1893 g of a polymer with a narrow particle size distribution. The mean diameter of the pores in the polymer is 42 nm.

[0081] 1.2. Preparation of a phthalimidomethylated, monodisperse, macroporous polymer using the swelling agent sulfur dioxide

[0082] In an autoclave, 53.1 g of polymer from Example 1.1 and 93.0 g (0.525 mol) of N-hydroxymethylphthalimide (177.2 g / mol) are placed. The autoclave is then evacuated, 600 g of sulfur dioxide (64 g / mol) are added, and the autoclave is closed. The mixture is stirred for 60 min at room temperature, and then 103 g (1.05 mol) of sulfuric acid (100 wt%, 98.1 g / mol) are added dropwise over 60 min at 40°C. The mixture is then stirred for 6 h at 50°C under a pressure of approximately 7.0 bar. Under these conditions, a high proportion of the sulfur dioxide is in a liquid state during the reaction. For work-up, the beads are washed successively with 78 wt% and 50 wt% sulfuric acid, and subsequently with water, acetone, and water. P001 01254 Abroad

[0083] - 13 -

[0084] Volume yield: 275 ml

[0085] Nitrogen content (after drying): 5.4% by weight

[0086] 1.3. Preparation of an aminomethylated, vinylaromatic, monodisperse, macroporous polymer

[0087] At room temperature, 250 ml of fully demineralized water and 95 g of a 50 wt% sodium hydroxide solution are placed in an autoclave. While stirring, 250 ml of resin are prepared and dosed according to Example 1.2.

[0088] The suspension is heated to 180°C and stirred at this temperature for a further 8 hours. It is then cooled. The resulting spherical polymer is separated using a sieve and washed neutrally with fully demineralized water.

[0089] Volume yield: 212 ml

[0090] Whole pearls: 99%

[0091] The spherical polymer remains stable after hydrolysis to the aminomethylated polymer, so that 99% of the polymer remains in a spherical state.

[0092] Example 2 (comparative example)

[0093] (not according to the invention)

[0094] 2.1 Preparation of a phthalimidomethylated, monodisperse, macroporous pearl polymer with phthalimide

[0095] In an autoclave, 53.1 g of polymer from Example 1.1, 77.2 g (0.525 mol) of phthalimide (147.13 g / mol), and 16.4 g (0.525 mol) of paraformaldehyde (30.03 g / mol (n = 8 to 30)) are placed. The autoclave is then evacuated, 600 g of sulfur dioxide (64 g / mol) are added, and the autoclave is closed. The mixture is stirred for 60 min at room temperature, and then 103 g (1.05 mol) of sulfuric acid (100 wt%, 98.1 g / mol) are added dropwise over 60 min at 40°C. The mixture is then stirred for 6 h at 50°C, with a pressure of approximately 7.1 bar. Under these conditions, a high proportion of the sulfur dioxide is in a liquid state during the reaction. For processing, the beads are washed successively with 78 wt% and 50 wt% sulfuric acid, and then with water, acetone, and water. P001 01254 Abroad

[0096] - 14 -

[0097] Volume yield: 310 ml

[0098] Nitrogen content (after drying): 5.4% by weight

[0099] 2.2 Preparation of an aminomethyl group-containing monodisperse, macroporous polymer. At room temperature, 268 ml of fully demineralized water and 118 g of a 50 wt% sodium hydroxide solution are placed in an autoclave. While stirring, 250 ml of resin are prepared, metered according to Example 2.1.

[0100] The suspension is heated to 180 °C and stirred at this temperature for a further 8 hours. It is then cooled. The resulting spherical polymer is separated using a sieve and washed neutrally with fully demineralized water.

[0101] Volume yield: 210 ml

[0102] Whole pearls: 15%

[0103] Only 15% of the spherical polymer remains in a spherical state.

[0104] The remaining spheres are not stable and break into small polymer pieces.

Claims

P001 01254 Abroad - 15 - Patent claims 1. Process for the production of amidomethylated, vinylaromatic Polymers characterized in that at least one vinylaromatic Polymer comprising at least one compound of formula (I) or its salts where R 1 = -C(H(Ci-C6-Alkyl))- or -CH2- and R 2 = -C(H(Ci-C6-Alkyl))- or -CH2- or R 1 and R 2 are two carbon atoms of an aromatic Ce ring, optionally substituted by one or two Ci-Ce alkyl groups, or R 1 and R 2 Each stands for -CH=, which is reacted in the presence of at least one protic acid and in the presence of sulfur dioxide.

2. Method according to claim 1, characterized in that the reaction is carried out at a pressure of 4 to 20 bar.

3. Method according to one of claims 1 or 2, characterized in that the reaction is carried out at a temperature of 30°C to 90°C.

4. Method according to one or more of claims 1 to 3, characterized in that sulfuric acid is used as the protic acid.

5. Method according to claim 4, characterized in that the concentration of the sulfuric acid used is 90 to 100 wt.%.

6. Method according to one or more of claims 1 to 5, characterized in that a styrene-divinylbenzene copolymer is used as the vinylaromatic polymer. P001 01254 Abroad - 16 - 7. Method according to one or more of claims 1 to 6, characterized in that N-hydroxymethylphthalimide is used as the compound of formula (I).

8. Method according to one or more of claims 1 to 7, characterized in that a monodisperse vinylaromatic polymer is used as the vinylaromatic polymer.

9. Method according to one or more of claims 1 to 8, characterized in that a macroporous vinylaromatic polymer is used and the pores have a diameter of > 25 nm.

10. Method according to one or more of claims 1 to 9, characterized in that the weight ratio of sulfur dioxide to the vinylaromatic polymer is 12:1 to 3:

1.

11. Method according to one or more of claims 1 to 10, characterized in that the stoichiometric ratio of the aromatic groups in the vinylaromatic polymer to the compounds of formula (I) is 0.7:1 to 1.6:

1.

12. Method according to one or more of claims 1 to 11, characterized in that the stoichiometric ratio of the compounds of formula (I) to the protic acid used is between 1 :1 and 1 :

3.

13. A process according to one or more claims 1 to 12, characterized in that the amidomethylated vinylaromatic polymer is reacted to form an aminomethylated vinylaromatic polymer in the presence of at least one alkali or alkaline earth metal hydroxide.

14. A process according to one or more claims 1 to 13, characterized in that the amidomethylated vinylaromatic polymer is reacted to form an aminomethylated vinylaromatic polymer in the presence of at least one alkali metal hydroxide and in the presence of water at a temperature of 100°C to 250°C.

15. Method according to claim 13 or 14, characterized in that the reaction takes place in the presence of sodium hydroxide.

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