Patent ID: 8580862

Claim:
A continuous process of making a silicone-in-water emulsion in an extruder, comprising: (i) forming a silicone polymer having a viscosity of at least 10,000 mm 2 /s at 25° C. by polymerization of one or more polyorganosiloxanes in the extruder; wherein polymerization is selected from (a) condensation polymerization of at least one polyorganosiloxane having at least one hydroxyl group capable of undergoing condensation polymerization; (b) ring-opening polymerization of at least one cyclosiloxane; (c) addition polymerization of a mixture of at least one polyorganosiloxane having at least one unsaturated aliphatic group and at least one hydrogen-terminated polyorganosiloxane; and (d) combinations thereof; wherein one or more catalysts, optionally one or more endblockers, and optionally one or more other additives are mixed with the polyorganosiloxanes; wherein polymerization is carried out in the absence of solvent other than solvents used as carriers for the catalysts, optional endblockers, and optional additives; (ii) optionally, neutralizing or stripping the silicone polymer in the extruder, wherein stripping can occur before, after, or without addition of a neutralizing agent; (iii) cooling the silicone polymer in a cooling zone of the extruder at a temperature between about 0° C. and about 60° C.; (iv) optionally, mixing one or more emulsifiers with the silicone polymer in the extruder; (v) optionally, adding water to the silicone polymer in the extruder; (vi) applying shear to form a silicone-in-water emulsion in the extruder; wherein the emulsion has a silicone polymer; wherein the emulsion has 0-0.3% by weight of at least one of octamethylcyclotetrasiloxanes and decamethylcyclopentasiloxanes; and (vii) optionally, diluting the emulsion in the extruder; wherein the extruder is selected from single-screw extruders and multi-screw extruders.