US 4,620,878 A · Method of preparing polyorganosiloxane emulsions having small particle size

Abstract

A method of preparing fine polyorganosiloxane emulsions with an average particle size of less than 0.3 micron and polyorganosiloxane microemulsions with an average particle size of less than 0.14 micron is described. A translucent oil concentrate is prepared by mixing a polyorganosiloxane which contains polar groups, a surfactant which is insoluble in the polyorganosiloxane, and sufficient water to obtain a translucent mixture. The translucent oil concentrate is then rapidly dispersed in water to form the desired fine emulsion or microemulsion. In general, if the translucent oil concentrate is not transparent a fine emulsion with an average particle size of less than 0.3 micron is obtained; whereas, if the oil concentrate is transparent, a microemulsion with an average particle size of less than 0.14 micron is obtained.

Claims97

Dependent claims

A process for preparing a polyorganosiloxane emulsion of the oil-in-water type, said process comprising

(A) forming a translucent oil concentrate by
(1) mixing a polyorganosiloxane with at least one surfactant where said polyorganosiloxane contains at least one polar radical attached to silicon through Si--C or Si--O--C bonds or at least one silanol radical where said polyorganosiloxane is liquid at the temperature of mixing, and where at least one of said surfactants is insoluble in said polyorganosiloxane at the temperature of mixing;
and
(2) adding water to the polyorganosiloxane and surfactant mixture of step (1) where water is added in an amount sufficient to produce a translucent oil concentrate;
and
(B) forming a polyorganosiloxane emulsion of the oil-in-water by rapidly dispersing said translucent oil concentrate in water where the average particle size of said polyorganosiloxane in said emulsion is less than 0.14 micron.

3 more elements

A process for preparing a polyorganosiloxane emulsion of the oil-in-water type, said process comprising

(A) forming a translucent oil concentrate by mixing a polyorganosiloxane, at least one surfactant, and water where said polyorganosiloxane contains at least one polar radical attached to Si through Si--C or Si--O--C bonds or at least one silanol radical, where said polyorganosiloxane is liquid at the temperature of mixing, where at least one of said surfactants is insoluble in said polyorganosiloxane at the temperature of mixing, and where water is present in an amount sufficient to produce a translucent oil concentrate;
and
(B) forming a polyorganosiloxane emulsion of the oil-in-water type by rapidly dispersing said translucent oil concentrate in water where the average particle size of said polyorganosiloxane in said emulsion is less than 0.14 micron.

An oil concentrate comprising

(A) a polyorganosiloxane which contains at least one polar radical attached to Si through Si--C or Si--O--C bonds or at least one silanol radical,
(B) a surfactant which is insoluble in said polyorganosiloxane
where said polyorganosiloxane and said surfactant form an opaque mixture, and
(C) a sufficient amount of water to produce a translucent mixture;
wherein said oil concentrate, when rapidly dispersed in water, will produce a polyorganosiloxane emulsion of the oil-in-water type with an average particle size of said polyorganosiloxane in said emulsion of less than 0.14 micron.

2 more elements

A polyorganosiloxane microemulsion of the oil-in-water type consisting essentially of

(A) a polyorganosiloxane which contains at least one polar radical attached to Si through Si--C or Si--O--C bonds or at least one silanol radical,
(B) a surfactant which is insoluble in said polyorganosiloxane, and
(C) water
wherein said polyorganosiloxane is the disperse phase and water is the continuous phase, wherein said polyorganosiloxane in said microemulsion has an average particle size of less than 0.14 microns and wherein said polyorganosiloxane microemulsion is transparent.

1 more element

Dependencies are inferred from the claim text.

Method of preparing polyorganosiloxane emulsions having small particle size

Life of this patent

Method of preparing polyorganosiloxane emulsions having small particle size

Life of this patent

Abstract

Claims97