Pituitous Silicone Fluids

Abstract

Fluid compositions are disclosed containing a branched organopolysiloxane and a carrier fluid. The branched organopolysiloxane is obtainable by reacting an organohydrogencyclosiloxane and an alkenyl terminated polydiorganosiloxane. The disclosed fluid compositions possess pituitous rheological properties.

1 . A fluid composition comprising:
 A) 0.1 to 50 wt % of a branched organopolysiloxane prepared by reacting;
 a) an organohydrogencyclosiloxane having the formula [(CH 3 )HSiO] g  
 where g is 3 to 8, and, 
 
 b) an alkenyl terminated polydiorganosiloxane comprising siloxy units of the formula (R 2 R 2 SiO 1/2 ) v (R 2 SiO 2/2 ) x  
 where v≧2, and x≧50, 
 R is an alkyl group containing 1 to 6 carbon atoms, 
 R 2  is an alkenyl group containing 2 to 12 carbon atoms, 
 
 in the presence of a hydrosilylation catalyst, where the molar ratio of alkenyl groups to SiH in the reaction is between 0.9/1 to 2.2/1, and 
   B) 50 to 99.9 wt % of a carrier fluid,   
       wherein the fluid composition has a viscosity of at least 100 mPa·s at 23° C. and exhibits pituitous rheological properties. 
     
     
         2 . The fluid composition of  claim 1  wherein the rheological properties of the fluid are determined from a plot of normal force in Pascals vs a perpendicular shear rate in sec −1  wherein the plot has an average slope that is greater than 3.6. 
     
     
         3 . The fluid composition of  claim 1  where the alkenyl terminated polydiorganosiloxane is a vinyl terminated polydimethylsiloxane. 
     
     
         4 . The fluid composition of  claim 3  wherein the vinyl terminated polydimethylsiloxane is a gum. 
     
     
         5 . The fluid composition of any of the above claims where g is 4. 
     
     
         6 . The fluid composition of  claim 1  where the carrier fluid is a hydrocarbon solvent. 
     
     
         7 . The fluid composition of  claim 1  consisting of;
 A) 0.1 to 50 wt % of a branched organopolysiloxane prepared by reacting;
 a) an organohydrogencyclosiloxane having the formula [(CH 3 )HSiO] g  
 where g is 3 to 8, and, 
 
 b) an alkenyl terminated polydiorganosiloxane comprising siloxy units the formula (R 2 R 2 SiO 1/2 ) v (R 2 SiO 2/2 ) x  
 where v≧2, and x≧50, 
 R is an alkyl group containing 1 to 20 carbon atoms, 
 R 2  is an alkenyl group containing 2 to 12 carbon atoms, 
 
 in the presence of a hydrosilylation catalyst, where the molar ratio of alkenyl groups to SiH in the reaction is between 0.9/1 to 2.2/1, and 
 
 B) 50 to 99.9 wt % of a carrier fluid, 
 
       where g is 4, the alkenyl terminated polydiorganosiloxane is a vinyl terminated polydimethylsiloxane. 
     
     
         8 . A personal care composition comprising the fluid composition according to  claim 1 .