A method for continuous bulk polymerization is disclosed that includes providing a planetary roller extruder having a plurality of planetary roller zones, introducing an acrylate monomer, a di-vinyl monomer, and a hydroxyl functional acrylic monomer into the planetary roller extruder, introducing an initiator into the planetary roller extruder for initiation of a free-radical polymerization of the acrylate monomer, the di-vinyl monomer, and the hydroxyl functional acrylic monomer to form an acrylic polymer, maintaining the temperature of the free-radical polymerization in the planetary roller extruder below 240° C., and discharging a portion of the acrylic polymer from the planetary roller extruder, and returning the portion of the acrylic polymer to one or more of the plurality of planetary roller zones.