Abstract: Heat-curable silicone compositions employing a reactive silicone, a silicone hydride crosslinker and a catalyst system which includes a rhodium-based catalyst, a stabilizing system are disclosed. A combination of rhodium and platinum-based catalysts are employed as well. The compositions are low temperature curing and are capable of providing low coefficient of thermal expansion compositions. A stabilizer system which includes in combination a peroxide and an acetylenic compound is also disclosed.

Abstract: The present invention provides novel “hybrid” silyl-terminated polymers that contain at least two different reactive end-capping groups. The “hybrid” silyl-terminated polymers of the present invention are produced by a novel single multi-step end-capping reaction of at least one silanol-terminated polymer with at least two silanes in the presence of a catalyst.

Abstract: The present invention relates generally to conductive, silicone-based compositions, with improved initial adhesion and reduced micro-voiding. More specifically, the present invention relates to a conductive, silicone-based composition, which includes a polyorganosiloxane, a silicone resin, and a conductive filler component.

Abstract: Heat-curable silicone compositions employing a reactive silicone, a silicone hydride crosslinker and a catalyst system which includes a rhodium-based catalyst, a stabilizing system are disclosed. A combination of rhodium and platinum-based catalysts are employed as well. The compositions are low temperature curing and are capable of providing low coefficient of thermal expansion compositions. A stabilizer system which includes in combination a peroxide and an acetylenic compound is also disclosed.

Abstract: Heat-curable silicone compositions employing a reactive silicone, a silicone hydride crosslinker and a catalyst system which includes a rhodium-based catalyst, a stabilizing system are disclosed. A combination of rhodium and platinum-based catalysts are employed as well. The compositions are low temperature curing and are capable of providing low coefficient of thermal expansion compositions. A stabilizer system which includes in combination a peroxide and an acetylenic compound is also disclosed.

Abstract: Heat-curable silicone compositions employing a reactive silicone, a silicone hydride crosslinker and a catalyst system which includes a rhodium-based catalyst, a stabilizing system are disclosed. A combination of rhodium and platinum-based catalysts are employed as well. The compositions are low temperature curing and are capable of providing low coefficient of thermal expansion compositions. A stabilizer system which includes in combination a peroxide and an acetylenic compound is also disclosed.

Abstract: The present invention relates to a process for preparing an alkoxy silyl-terminated material, which has at least two alkoxy groups on both terminal ends, said process comprising reacting in the presence of a catalytically effective amount of an organo-lithium reagent an alkoxysilyl-terminated first reactant with a second reactant having both ends of its chain terminating in a silanol. The alkoxy silyl-terminated material may have a variety of polymer backbone types such as silicone, polyurethane, polyamide and the like. These materials are intended to cure by either moisture or photo cure or by dual moisture and photo cure mechanisms. The alkoxy silyl-terminated material is preferably an organopoly-siloxane having at least two alkoxy groups at both terminal ends.

Abstract: An impregnation sealant composition comprises a low viscosity vulcanizable silicone. The silicone is selected from the group consisting of (i) a heat curable silicone composition formed as the reaction product in the presence of a platinum catalyst of a first silicon containing material containing at least two SiH functionalities and having a molecular weight less than 2000 with a second silicon containing material containing at least two ethylenically unsaturated functionalities and having a molecular weight less than 2000, said silicone composition having a ratio of SiH to Si-ethylenically unsaturated functionalities of from about 0.8 to about 1.2; and (ii) a room temperature vulcanizing silicone composition formed as the reaction product of a silicone fluid containing at least two SiOH functionalities and having a molecular weight less than 2000 with a silane cross-linker of formula (I):R.sub.n Si(X).sub.

Abstract: An anaerobically curing composition is comprised of (i) a silicone fluid formed as the reaction product of at least one first silane of formula I:R.sub.n Si(X).sub.4-n (I),wherein the R groups are the same or different and selected from the group consisting of hydrogen, C1-C12 alkyl, C6-C12 aryl, C7-C18 arylalkyl, C7-C18 alkylaryl, haloalkyl, haloaryl and monovalent ethylenically unsaturated radicals excluding (meth)acryloxy functional groups, X is a hydrolyzable functionality, and n is an integer of from 0 to 3, and at least one second silane of formula II:R.sup.1.sub.m R.sup.2.sub.p Si(X).sub.4-(m+p) (II),wherein R.sup.1 is a (meth)acrylic functional group and R.sup.

Abstract: A radiation and moisture curable silicone conformal coating composition comprises a silicone fluid of a monovalent ethylenically unsaturated functional group endcapped silicone and at least one (meth)acryl-functionalized silicone; and a photoinitiator effective for radiation curing of the silicone composition. The encapped silicone is the product of a reaction between a silanol terminated silicone and a silane cross linker having joined directly to a silicon atom thereof a monovalent ethylenically unsaturated functional group and at least 2 hydrolyzable groups.

Abstract: A radiation surface-curable RTV silicone composition which subsequent to radiation surface curing thereof, is interiorly moisture-curable in character. Such radiation surface-curable, interiorly moisture-curable RTV silicone composition comprises: a silanol-containing silicone; a silane cross-linker for the silicone, such cross-linker having joined directly to a silicon atom thereof an ethylenically unsaturated functional group and at least two hydrolyzable functional groups; and a photoinitiator effective for radiation surface curing of the silicone composition. Also disclosed is a "liquid potting system" formulation, which is irradiated subsequent to dispensing thereof at the potting locus, so that the radiation surface-cured skin layer overlies and contains (cooperatively with the associated bounding surface(s) of the potting locus) the uncured liquid, so that the potted structure or material is encapsulated in a liquid (damping) medium.

Abstract: Photocurable silicone compositions based on capping of a silicone with a silyl diacrylate capper of the formula ##STR1## wherein: R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9, and R .sub.10 are independently selected from hydrogen, halo, and organo radicals; and n is an integer having a value of from 1 to 4.In specific embodiments, the compositions include a polymodal-cure resin composition comprising an acryloxy-functional capped silicone, and a photocurable silicone gel composition and precursor thereof.

Abstract: The present invention relates to a process for preparing an alkoxy silyl-terminated material, which has at least one alkoxy group on at least one terminal end, said process comprising reacting in the presence of a catalytically effective amount of an organo-lithium reagent an alkoxysilyl-terminated first reactant with a second reactant having at least one end of its chain terminating in silanol groups. The alkoxy silyl-terminated material may have a variety of polymer backbone types such as silicone, polyurethane, polyamide and the like. These materials are intended to cure by either moisture cure or by dual moisture and photo cure mechanisms. The alkoxy silyl-terminated material is preferably an organopoly-siloxane having alkoxy groups at its terminal ends. The resultant alkoxy-terminated organopolysiloxanes are substantially stable materials as measured by preservation and maintenance of viscosity values (cps) over time.

Abstract: An acryloxy-functional capped silicone formed as a reaction product of:(i) a silyl diacrylate compound of the formula ##STR1## wherein: R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9, and R.sub.10 are independently selected from hydrogen, halo, and organo radicals; and n is an integer having a value of from 1 to 4; and(ii) a silicone having (A) functionality which is reactive with an acryloxy functionality of the silyl diacrylate compound, and (B) additional functionality imparting (directly or by reaction with a co-reactant) further curability to the silicone by another modality (e.g., moisture curability, heat curability, etc.)The capped polyfunctional silicone may suitably be formulated with (a) an effective amount of a photoinitiator for partial curing of the acryloxy-functional capped silicone under photoinitiating curing conditions, and (b) suitable curatives, initiators, accelerators, etc.

Abstract: A silicone composition comprising:(a) a first silane of the formula: ##STR1## wherein: R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9, and R.sub.10 are independently selected from hydrogen, halo, and organo radicals; andn is an integer having a value of from 1 to 4;(b) a second silane of the formula: ##STR2## wherein: R.sub.11 and R.sub.16 are non-polymerizable groups and are independently selected from halo and organo radicals;R.sub.12, R.sub.13, R.sub.14, and R.sub.

Abstract: An acryloxy-functional capped silicone formed as a reaction product of:(i) a silyl diacrylate compound of the formula: ##STR1## wherein: R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9, and R.sub.10 are independently selected from hydrogen, halo, and organo radicals; andn is an integer having a value of from 1 to 4; and(ii) a silicone having at least one functionality which is reactive with an acryloxy functionality of the silyl diacrylate compound to yield the acryloxy-functional capped silicone.The capped silicone may suitably be formulated with an effective amount of a photoinitiator for curing of the acryloxy-functional capped silicone under photoinitiating curing conditions. The silicone functionality which is reactive with the acryloxy functionality of the silyl diacrylate compound may be --OH, or other labile hydrogen-containing substituent. Preferably, the silicone is a hydroxy-terminated linear polydiorganosiloxane.