Process for macroporous acrylic resins
View Patent ↗A macroporous core-shell resin bead having carboxylic acid groups; the bead has from 3% to 100% of monomer residues derived from crosslinker, an average pore diameter of at least 1.5 nm, and an average particle size from 10 μm to 900 μm; wherein at least 90% of the carboxylic acid groups in the bead are in the shell region, and the shell region comprises from 5% to 75% of the bead by volume.
1. A macroporous core-shell resin bead having carboxylic acid groups; said bead comprising a core region surrounded by a shell region; said bead having from 3% to 100% of monomer residues derived from crosslinker, an average pore diameter of at least 1.5 nm, and an average particle size from 10 μm to 900 μm; wherein at least 90% of the carboxylic acid groups in the bead are in the shell region, and the shell region comprises from 5% to 75% of the bead by volume.
2. The bead of claim 1 in which the average particle size is from 100 μm to 500 μm, the shell region comprises from 5% to 50% of the bead by volume and the bead has from 5% to 30% of monomer residues derived from crosslinker.
3. The bead of claim 2 which is an acrylic resin.
4. The bead of claim 3 comprising from 8% to 30% of monomer residues derived from crosslinker.
5. The bead of claim 4 in which the shell region comprises from 10% to 30% of the bead by volume.
6. The bead of claim 5 in which at least 95% of the carboxylic acid groups in the bead are in the shell region.
7. The bead of claim 1 comprising from 80% to 100% of monomer residues derived from crosslinker.