摘要:
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.
摘要:
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., as necessary or desirable for further curing by other cure mechanisms dissociated with the additional functionality (ii) (B). The compositions of the invention are usefully employed as adhesives, sealants, conformal coatings, potting materials, and the like.
摘要:
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.
摘要:
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. The compositions of the invention are usefully employed as sealants, conformal coatings, potting materials, and the like, and are readily curable with UV radiation.
摘要:
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. The resultant alkoxy-terminated organopolysiloxanes are substantially stable materials as measured by preservation and maintenance of viscosity values (cps) over time and exhibit a higher crosslinking density when cured due to a higher degree of endcapping as compared to the prior art.
摘要:
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.15 are independently selected from hydrogen, halo, and organo radicals; andn is an integer having a value of from 1 to 4; and(c) a polysiloxane having at least two functional groups per molecule with which said first and second silanes are cappingly reactive;wherein: (1) the first and second silanes together are provided in sufficient quantity relative to the polysiloxane to react with substantially all of the cappingly reactive functional groups of the polysiloxane; and (2) the first silane constitutes from about 50% to about 98% by weight of the total weight of the first and second silanes.
摘要:
The present invention relates to a method of preparing fast curing silicone RTV compositions by reacting an amino endcapped silicone with an isocyanato functionalized silane, and to compositions formed thereby. In particular, the present invention provides compositions which include silicones endcapped with silanes which contain α-ureas. Illustrative of the inventive compositions are those which include a polymer of Formula (I):
摘要:
The present invention relates to a process for forming a cured-in-place gasket by liquid injection molding. More particularly, the present invention relates to a low pressure and room temperature process for forming a cured-in-place gasket by liquid injection molding.
摘要:
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.
摘要:
The present invention relates to a process for forming a cured-in-place gasket by liquid injection molding. More particularly, the present invention relates to a low pressure and room temperature process for forming a cured-in-place gasket by liquid injection molding.