Patent ID: 8513322

Claim:
A method of making a polymeric bead, the method comprising: providing a precursor composition comprising: a) greater than 10 weight percent polar solvent based on a total weight of the precursor composition, wherein the polar solvent is not a monomer and wherein the polar solvent is water, a water-miscible organic solvent, or a mixture thereof; and b) polymerizable material capable of free-radical polymerization and having an average number of ethylenically unsaturated groups per monomer molecule equal to at least 1.5 based on all of the polymerizable material in the precursor composition, wherein the polymerizable material is miscible with the polar solvent and wherein the polymerizable material comprises a poly(alkylene oxide (meth)acrylate) having at least 2 (meth)acryloyl functionality groups and having at least 10 alkylene oxide units; forming a droplet of the precursor composition, wherein the droplet is totally surrounded by a gas phase; and exposing the droplet to radiation for a time sufficient to at least partially polymerize the polymerizable material and to form a first swollen polymeric bead.