Dow Corning Corporation

Case Western Reserve University

Virginia Institute and State University

Timothy Chi-Shan Chao

Dimitris Katsoulis

Gary Thomas Burns

Malcolm Edward Kenney

Ronald Paul Boisvert

Satyendra Kumar Sarmah

Aref Ben Jallouli

A method of preparing a hydrophobic partially aggregated colloidal silica, the method comprising reacting (a) a silica sol comprising at least one hydrophilic partially aggregated colloidal silica with (b) an organosilicon compound selected from (i) at least one organosilane having the formula R H SiX , (ii) at least one organocyclosiloxane having the formula (R SiO) , (iii) at least one organosiloxane having the formula R SiO(R SiO) SiR , and (iv) a mixture comprising at least two of (i) (ii), and (iii), in the presence of (c) water (d) an effective amount of a water-miscible organic solvent, and (e) an acid catalyst, to produce the hydrophobic partially aggregated colloidal silica and an aqueous phase, wherein R is hydrocarbyl or substituted hydrocarbyl; X is a hydrolysable group; a is 0, 1, 2, or 3; b is 0 or 1; a&plus;b&equals;1, 2, or 3, provided when b&equals;1, a&plus;b&equals;2 or 3; m has an average value of from 3 to 10; and n has an average value of from 0 to 10; and the hydrophobic partially aggregated colloidal silica produced by the method.

Method of preparing hydrophobic partially aggregated colloidal silica

A filled silicone composition comprising (A) a curable silicone composition and (B) 5 to 60% (w/w) of a hydrophobic partially aggregated colloidal silica; and a cured silicone product comprising a reaction product of the filled silicone composition.

Filled silicone composition and cured silicone product

Polysiloxane sheet or tube polymers having pendant siloxane groups are prepared by contacting sheet or tube silicates with halogen endblocked halosiloxanes represented by the formula: ##STR1## where X is chlorine, fluorine, bromine, or iodine; R1 to R7 are alkyl groups with 1-6 carbon atoms, aryl groups, alkaryl groups, or aralkyl groups; in which one of the groups R1, R4, and R5 can additionally represent X; and n has a value of 2 to about 20.

Sheet and tube polymers with pendant siloxane groups

A polymer matrix composite comprises a matrix of a cured methylsilsesquioxane resin and a reinforcing material. The composite has low heat release rate, smoke yield, and carbon monoxide yield when burned. After burning, the composite has high char yield and retains much of its initial tensile strength. The method for making the composite comprises applying a silanol-functional methylsilsesquioxane resin comprising 70 to 90 mol % ((CH.sub.3)SiO.sub.3/2) units and 10 to 25 mol % (CH.sub.3 Si(OH)0.sub.2/2) units to a reinforcing material and curing the resin.

Silicone resin composites for fire resistance applications and method

Organopolysiloxane sheet or tube polymers are made by contacting a sheet or tube silicate with an alkenyl group containing chlorosilane to form an alkenylsiloxy polymer, and subsequently contacting the alkenylsiloxy sheet or tube polymer with a hydrosilane or hydrosiloxane in the presence of a hydrosilation catalyst, to catalyze a reaction between the alkenyl group on the alkenylsiloxy polymer and hydride functionality on the hydrosilane or hydrosiloxane. Silylalkoxysiloxane sheet or tube polymers are made by contacting a sheet or tube silicate with an acidic solution of an alkenyl alcohol to form a polymeric sheet or tube alkenyloxysiloxane, and subsequently contacting the alkenyloxysiloxane with a hydrosilane or hydrosiloxane in the presence of a hydrosilation catalyst, to catalyze a reaction between the alkenyl group on the alkenyloxysiloxane and hydride functionality on the hydrosilane or hydrosiloxane.

Growing community of inventors

Midland, MI, United States of America

Timothy Chi-Shan Chao