Abstract: The invention provides reinforced aerogel monoliths as well as reinforced composites thereof for a variety of uses. Compositions and methods of preparing the monoliths and composites are also provided. Application of these materials in transparent assemblies is also discuss.

Abstract: Adhesion promoting additives for organosiloxane compositions that cure by a platinum-catalyzed hydrosilation reaction are reaction products of (1) an ethylenically unsaturated ether of a polyfunctional alcohol and (2) at least one silicon compound selected from the group consisting of (i) epoxy-substituted organosilicon compounds containing at least one hydrolyzable group per molecule and (ii) tetraalkyl orthosilicates, also referred to tetraalkoxysilanes, where the reaction is conducted in the presence of a suitable catalyst such as an organotitanium compound. The additive optionally includes a chelated organoaluminum compound.

Abstract: The present invention utilizes a class of novel hydrosilation catalysts that are inhibited in the absence of molecular oxygen to prepare storage stable, one part curable compositions containing (1) compounds with alkenyl radicals and (2) compounds with silicon-bonded hydrogen atoms. The compositions are stable until exposed to molecular oxygen, at which time they cure in the same manner as conventional compositions containing these ingredients.

Abstract: Curable polyorganosiloxanes prepared using a base-catalyzed equilibration reaction involving at least one organosiloxane are treated with a composition that includes a triorganohalosilane to neutralize the catalyst. The silane can be used alone or in combination with other Lewis acids. Curable compositions containing polyorganosiloxanes prepared using the present method exhibit improved thermal stability relative to compositions containing polyorganosiloxanes prepared using prior art neutralizing agents.

Abstract: This invention relates to a method of forming a ceramic coating on a substrate. The method comprises coating the substrate with a solution comprising a solvent and a silica precursor followed by evaporating the solvent to form a preceramic coating. The preceramic coating is then exposed to an environment comprising ammonium hydroxide or an environment to which water vapor and ammonia vapor have been added to facilitate conversion of the silica precursor to the ceramic coating. The preceramic coating is then subjected to a temperature sufficient to facilitate conversion of said preceramic coating to a ceramic coating.

Abstract: The presence of both an organotitanium compound and a microencapsulated platinum-containing hydrosilation catalyst in organosiloxane compositions curable by a hydrosilation reaction not only increases the heat stability of elastomers prepared from the composition, but also unexpectedly increases the cure rate of the compositions. In addition to the platinum-containing and organotitanium co-catalysts the curable compositions comprise an organohydrogenpolysiloxane curing agent and a liquid or high consistency organopolysiloxane containing an average of at least two ethylenically unsaturated hydrocarbon radicals per molecule.

Abstract: Storage stable and gel-free organosiloxane compositions in the form of flowable powders are prepared by blending a high consistency polydiorganosiloxane into a quantity of fluidized reinforcing filler that is heated to a temperature of from 100.degree. to 200.degree. C. prior to or immediately following introduction of the polydiorganosiloxane. When silica is the reinforcing filler, the filler is typically treated with an anti-creping agent either prior to or during this blending process. The resultant mixture is heated while being subjected to shearing forces that reduce its average particle size to achieve a flowable powder.

Abstract: This invention relates to a low temperature method of converting coatings of hydrogen silsesquioxane resin or hydrolyzed or partially hydrolyzed R.sub.X Si(OR).sub.4-X to ceramic silica coatings. The method comprises applying a silica precursor coating to a substrate, exposing the coating to an environment comprising an amine and subjecting the coating to a temperature sufficient to yield the ceramic coating. The methods of the invention are particularly applicable to applying coatings on electronic devices.

Abstract: The silacyclobutane functional polydiorganosiloxane copolymers of the invention have the following structure: ##STR1## wherein M is selected from ##STR2## wherein R.sup.a, R.sup.b, R.sup.c, R.sup.d, R.sup.e, and R.sup.f are independently monovalent radicals selected from the group consisting of hydrogen, hydrocarbon, or substituted hydrocarbon; m and x are integers of from 0 or more; n is equal to 1; and p is an integer greater than 0; with the proviso that there is at least one silacyclobutane group in the copolymer. The copolymer can be made by reacting a hydroxyl endblocked polydiorganosiloxane with either a difunctional chain extending silacyclobutane or with a monofunctional chain stopper, or a mixture of chain extender and chain stopper. The copolymer can be made into curable compositions by use of suitable catalyst.

Abstract: This invention describes a polycyclosiloxane of the formula ##STR1## where R.sup.a, R.sup.b, and R.sup.c are independently monovalent radicals; x is an integer equal to or greater than 3, y is equal to or greater than 0, and x plus y is greater than 3. A process for the production of the polycyclosiloxane above consisting essentially of (A) adding a solvent solution of 1,1-dichlorosilacyclobutane, and optionally dichlorodiorganosilane, to a mixture of water and solvent with rapid stirring at room temperature at a rate which does not cause the mixture to raise in temperature, (B) washing with water, (C) drying with MgSO.sub.4, (D) filtering, and (E) removing the solvent. Methods of using the polycyclosiloxane of silacyclobutane as an ingredient in a silicone composition which cures on exposure to moisture to give an elastomer is claimed, as is the composition produced.

Abstract: An aqueous, silicone emulsion of polydiorganosiloxane having silacyclobutane groups comprises the product obtained by the emulsion polymerization of a mixture of polydiorganosiloxane oligomer having hydroxyl endblocking and silacyclobutane containing silicone material. Adding a nucleophilic material to the emulsion produces an emulsion which yields an elastomer upon removal of the water from the emulsion. The elastomer from this emulsion can be reinforced by adding an aqueous, dispersed fume silica to the emulsion before removal of the water.

Abstract: Novel silacyclobutanes useful as silylating agents and a process for their preparation are provided. The process comprises reacting a halogen substituted silacyclobutane with a silylating reagent to exchange the halogen substituents with groups on the silylating reagent.

Abstract: Novel silacyclobutanes useful as silylating agents and a process for their preparation are provided. The process comprises reacting a halogen substituted silacyclobutane with a silylating reagent to exchange the halogen substituents with groups on the silylating reagent.

Abstract: A method of producing alkoxysilethylene endblocked polydiorganosiloxane consists essentially of first reacting hydroxyl endblocked polydiorganosiloxane with an excess of a SiH compound having from 2 to 4 SiH groups in the presence of a platinum catalyst, then reacting that product with vinyltrialkoxysilane to give the desired polymer.

Abstract: Extrudable organosiloxane compositions that cure by a hydrosilation reaction comprise a first polydiorganosiloxane containing alkenyl radicals only at the terminal positions of each molecule and a second polydiorganosiloxane containing alkenyl radicals on both terminal and non-terminal silicon atoms. When the alkenyl radicals on at least the second of the two polydiorganosiloxanes contain at least four carbon atoms the cure rate of the compositions is substantially increased relative to compositions wherein the alkenyl radicals on this polymer are vinyl.