Abstract: A process for pelletizing elastomeric anionically polymerized polymers which comprises subjecting the polymer to solid state extrusion in a single screw extruder with a length to diameter ratio of 10:1 or less wherein the barrel of the extruder has longitudinal grooves and transversally extending pins to increase mixing wherein the temperature in the extruder is sufficient to agglomerate or melt the polymer but be lower than the degradation temperature of the polymer and the speed of the extruder screw is from 30 to 100 rpm.

Abstract: A process for finishing a hydrogenated diene polymer by producing porous pellets from a water slurry of the hydrogenated block copolymer. The process comprises adjusting the water content of the slurry to from 9 to 16 percent by weight, moving the slurry through a mechanical two-stage extruder dryer, drying the slurry at a temperature of 100 to 180° C., and recovering porous copolymer pellets having a moisture content of 0.2 to 3.0 percent by weight.

Abstract: In a process for producing hydrogenated block copolymers of conjugated dienes and/or vinyl aromatic hydrocarbons which comprises anionically polymerizing the monomers in an inert hydrocarbon solvent in the presence of an alkali metal initiator whereby a polymer cement is produced, contacting the cement with hydrogen under hydrogenation conditions in the presence of a hydrogenation catalyst, and then removing the hydrogenation catalyst residue by washing the polymer cement with water or an aqueous acid, the improvement which comprises reducing the viscosity of the polymer cement by polymerizing the block copolymer under conditions such that the vinyl content of the polymer produced in the polymerization step is in the range from 45 to 80 percent by weight.