Process for preparing aminomethylated bead polymers
Aminomethylated bead polymers for use as ion exchangers, especially as anion exchangers, or for the preparation of chelate resins, are prepared in the presence of 1,3-dichloropropane as solvent and swelling agent.
1. A process for preparing aminomethylated bead polymers, the process comprising:
contacting monodisperse bead polymer comprising units based on styrene and divinylbenzene with:
compounds of the formula (I) or salts thereof
where R 1 =C 1 -C 3 -alkyl or H,
compounds of the formula (II)
where n=8 to 100,
1,3-dichloropropane, and
sulfuric acid,
wherein:
about 7.5 to about 13 mol of the 1,3-dichloropropane is used per mole of the bead polymer; and
about 3.5 to about 13 mol of the 1,3-dichloropropane is used per mole of the compounds of the formula (I);
to produce phthalimidomethylated bead polymer; and
hydrolysing the phthalimidomethylated bead polymer to produce aminomethylated bead polymer.
2. The process according to claim 1 , wherein R 1 =H.
3. The process according to claim 1 , wherein the 1,3-dichloropropane is both a solvent and a swelling agent in the process, and the amount of 1,3-dichloropropane used, based on a total amount of solvents and swelling agents used, is greater than 90% by weight.
4. The process according to claim 1 , wherein the contacting is conducted at a temperature of about 55° C. to about 75° C.
5. The process according to claim 1 , wherein the contacting comprises:
swelling the bead polymer in the 1,3-dichloropropane to form swelled bead polymer;
combining the swelled bead polymer, the compounds of the formula (I), and the compounds of the formula (II) to form a mixture; and
adding the sulfuric acid to the mixture.
6. The process according to claim 1 , wherein the hydrolyzing is in the presence of aqueous or alcoholic solutions of an alkali metal hydroxide at temperatures of about 100° C. to about 250°C.
7. The process according to claim 1 , wherein the monodisperse bead polymer comprises macroporous, monodisperse bead polymer, and the aminomethylated bead polymer produced is a macroporous aminomethylated bead polymer.
8. The process according to claim 1 , wherein the 1,3-dichloropropane is both a swelling agent and a solvent in the process, and no additional swelling agent or solvent is used.
9. The process according to claim 1 , wherein:
the process further comprises polymerizing monomer droplets of a mixture comprising styrene, divinylbenzene, and at least one initiator to produce the monodisperse bead polymer, wherein:
the initiator is selected from a group consisting of dibenzoyl peroxide, dilauroyl peroxide, bis(p-chlorobenzoyl) peroxide, dicyciohexyl peroxydicarbonate, tert-butyl peroctoate, tert-butyl peroxy-2-ethylhexanoate, 2,5-bis(2-ethylhexanoyiperoxy)-2,5-dimethylhexane, tert-amylperoxy-2-ethylhexane, 2,2′-azobis(isobutyronitrile), and 2,2′-azobis(2-methylisobutyronitrile) and mixtures of these compounds; and
the monomer droplets are microencapsulated with polyesters, natural polyamides, synthetic polyamides, polyurethanes, or polyureas;
R 1 =H; and
the 1,3-dichloropropane is both a swelling agent and a solvent in the process, and the amount of 1,3-dichloropropane used, based on a total amount of solvents and swelling agents used, is at least 95% by weight.
10. The process according to claim 9 , wherein at least one further swelling agent and/or solvent, in addition to the 1,3-dichloropropane, is used, and the at least one further swelling agent and/or solvent comprises at least one swelling agent and/or solvent selected from the group consisting of: 1,2-dichloroethene, 1,2-dichloropropane, 1,4-dichlorobutane, 1,6-dichlorohexane, methylene chloride, carbon tetrachloride, trichloroethane, chlorobenzene, 1,2-dichlorobenzene, nitropropane, nitrobenzene, cyclohexane, and methylcyclohexane.
11. The process according to claim 9 , wherein:
the polymerizing of the monomer droplets is in the presence of a porogen;
the contacting is conducted at a temperature of about 55° C. to about 75° C.;
an amount of the 1,3-dichloropropane is about 6 to about 9 mol per mole of compounds of the formula (I); and
the contacting comprises:
swelling the bead polymer in the 1,3-dichloropropane to form swelled bead polymer;
combining the swelled bead polymer, the compounds of the formula (I), and the compounds of the formula (II) to form a mixture; and
adding the sulfuric acid to the mixture; and
the hydrolyzing is in the presence of aqueous or alcoholic solutions of an alkali metal hydroxide at temperatures of about 100° C. to about 250° C. to produce macroporous aminomethylated bead polymer.
12. The process according to claim 11 , wherein:
an amount of the compounds of the formula (I) is about 0.6 mol per mole of sulfuric acid; and
the amount of 1,3-dichloropropane used, based on a total amount of swelling agent and solvent used, is 100% by weight.