Silicone MQ resin reinforced silicone elastomer emulsions
AssigneeDow Corning Corporation
InventorYihan Liu
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Abstract
An aqueous silicone emulsion forms a resin reinforced elastomeric film upon water evaporation. The emulsion composition contains a dispersed phase consisting of a silicone mixture composed of (i) a linear hydroxy terminated polydiorganosiloxane, (i) a silicone MQ resin, and (iii) an organofunctional polysiloxane. The aqueous silicone emulsion is prepared by mixing ingredients (i) to (iii) to form a mixture, adding emulsifiers and water to the mixture, mixing the ingredients to obtain an aqueous base emulsion, adjusting the pH of the base emulsion to an acidic or basic pH to facilitate crosslinking, and subsequently neutralizing the emulsion. Elastomeric films can be obtained by drying the emulsion on a substrate at ambient conditions.
Claims6
A method of making an aqueous silicone emulsion containing a crosslinked silicone elastomer comprising mixing;
- (i) 1-95 parts by weight of a linear hydroxy terminated polydiorganosiloxane,
- (ii) 5-60 parts by weight of a silanol containing silicone MQ resin, providing there is at least 40 parts of component (ii) per 100 parts of component (i), and
- (iii) 0.1-30 parts by weight of an organofunctional polysiloxane, to form a water-insoluble homogeneous silicone oil phase;
- admixing at least one emulsifier and water to the silicone oil phase to obtain an aqueous silicone base emulsion;
- adding a sufficient amount of an acidic or basic compound to the aqueous silicone base emulsion in order to adjust the pH of the aqueous silicone base emulsion to an acidic or basic pH necessary to facilitate condensation and crosslinking of the linear hydroxy terminated polydiorganosiloxane and the silanol containing silicone MQ resin in forming a crosslinked silicone elastomer;
- and neutralizing the aqueous silicone emulsion containing the crosslinked silicone elastomer.
Dependencies are inferred from the claim text.