Abstract: Isotropic porous polymer beads having a high surface porosity and large pore diameters from about 0.002 to about 5 microns are produced from solutions of a polymer or a copolymer by a thermally-induced phase separation process. The use of mixed solvent-non-solvent combinations as solvents for the polymers, produces high pore content, substantially spherical beads having a morphology ideally suited to the chromatography of large molecules, such as proteins, and for enzyme-binding.

Abstract: A porous shaped substrate such as a porous bead is formed from polyacrylonitrile or a copolymer thereof containing nitrile groups. The substrate has a hydrophilic surface containing amide groups constituting about 1.8 mole percent to less than about 15 mole percent of the total nitrile groups, and containing no amide or carboxyl groups. The substrate is substantially non-swellable in water and is able to resist pressures in a columnar bed of up to about 3000 psi without collapsing. In forming the amide groups, polyacrylonitrile or copolymer thereof containing nitrile groups, an alkaline catalyst such as sodium hydroxide and a nonsolvent for the substrate such as methanol are combined to form a suspension. A peroxide is added to the suspension and the suspension is heated to hydrolyze nitrile groups to amide groups. Succinylated aminoethyl groups or activated carboxyl groups can be formed on the substrate and a bioactive ligand such as p-aminobenzamidine covalently bonded to the substrate.

Abstract: Isotropic porous polymer beads having a high surface porosity and large pore diameters from about 0.002 to about 5 microns are produced from solutions of an acrylonitrile polymer or a copolymer by a thermally-induced phase separation process. The use of mixed solvent-non-solvent combinations as solvents for the polymers, produces high pore content, substantially spherical beads having a morphology ideally suited to the chromatography of large molecules, such as proteins, and for enzyme-binding.

Abstract: Isotropic porous polymer beads having controllable surface porosity and large pore diameters from about 0.002 to about 5 microns are produced from solutions of an acrylonitrile polymer or a copolymer by a thermally-induced phase separation process including intensively shearing the polymer solution into small droplets. The use of mixed solvent non-solvent combinations as solvents for the polymers, and preferably reducing the polymer content in solution to below 10 percent produces high pore content, substantially spherical beads having a morphology ideally suited to the chromatography of large molecules, such as proteins, and for enzyme-binding.