Emulsion Polymerized Emulsions from Polydimethyl Siloxane Mixture and Consequence of Cyclic Generation in Final Emulsion

A commercial manufacturing process of a stable emulsion having particle size (D50 value) of up to 1000 nanometer and cyclosiloxane content of upto 3000 ppm comprising:

• i) providing a formulation comprising
• (a) a starting organopolysiloxane comprising two or more organopolysiloxane which is the same or different of general formula (I) or its mixture
• where R1 is same or different and is a monovalent hydrocarbon group of 1 to 10 carbon atoms or a hydroxyl group or an alkoxy group having 1 to 8 carbon atoms,
• R is same or different and is a monovalent hydrocarbon radical,
• x is same or different and is an integer from 1 to 2000,
• (b) water,
• (c) a non-ionic emulsifier(s) having HLB in the range of 8-19 and
• (d) a neutralized anionic emulsifier;
• ii) homogenizing the formulation using any standard homogenizer and maintaining a temperature up to 35° C.;
• iii) cooling the formulation below a temperature of 12° C.;
• iv) adding an anionic emulsifier to obtain an organopolysiloxane polymer with viscosity of at least 20000 mPa·s at 25° C.;
• and
• iii) neutralizing the emulsion by alkali to a pH range of 6 to 8.