A mechanical method of making an oil-in-water microemulsion containing (A) a polysiloxane and (B) an inert fluid selected from an inert siloxane fluid and an inert organic fluid, where the average emulsion particle size is between 1 and 140 nanometers, is disclosed. The process involves the following steps: i) preparing an oil phase comprising a polysiloxane containing mixture by the polymerization of silane or siloxane containing monomers and/or oligomers in the presence of an inert fluid, a suitable catalyst and optionally an end-blocking agent； and ii) where required quenching the polymerization process； wherein the inert fluid is substantially retained within the resulting polysiloxane containing mixture； iii) if required, mixing one or more surfactants into the oil phase； iv) adding water to the oil phase, followed by applying agitation or shear to the mixture to arrive at an oil-in-water microemulsion； v) optionally diluting the oil-in-water microemulsion by adding more water.
