Abstract: This invention is directed to stabilizing additives that contain at least one platinum complex, with the complex including a carbene group. The stabilizing additives make it possible to improve the resistance to decomposition of silicone elastomers under high temperatures. The additive can be used in a polyorganosiloxane composition intended for the production of a silicone elastomer with either crosslinks at high temperature under the action of organic peroxides or crosslinks at ambient temperature or with heat by polyaddition reactions in the presence of a metal catalyst.

Abstract: A process for production of an assembly including several silicone elements crosslinked by polyaddition of ?Si—H units onto ?Si-alkenyl (preferably ?Si-vinyl) units, the elements adhering to one another without detracting from their mechanical properties. The process includes: (I) forming (1st coating) a silicone element (i) with a liquid silicone preparation (i) containing polyorganosiloxanes (POS) A with ?Si-vinyl units, (POS) B with ?Si—H units, a platinum catalyst C; (II) crosslinking so that (i) has a surface density SD of unreacted, residual vinyl, per nm2, of 0.0100?SD?0.0040; (III) optionally repeating steps (I) and (II) n times to give n elements (i) that adhere to one another; (IV) forming (2nd coating) a silicone element (ii) with a liquid silicone preparation (ii) of the same type as described above; (v) crosslinking to give crosslinked (ii) that adheres to (i).

Abstract: The invention concerns the use as additive for improving properties of resistance to arc tracking and arc erosion: of a mixture A, B or C formed by: concerning mixture A: A1: platinum; and A2: at least an inorganic compound A2.1 of a metal with several degrees of oxidation selected from the group formed by V, Cr, Mn, Fe, Co, Ni, and Cu, in which the metal atom is at a degree of oxidation higher than zero, the least possible (abbreviation: DOX mini); or A3: a combination of at least an inorganic compound A2.1 with at least an inorganic compound A2.2 in which the atom of V, Cr, Mn, Fe, Co, Ni or Cu is at a degree of oxidation higher than DOX mini; concerning mixture B: B1 platinum; and B2: at least an inorganic compound B2.1 of cerium-IV or of lanthanum-III; or B3: a combination of at least an inorganic compound B2.1 with at least an inorganic compound B2.

Abstract: Single-component silicone elastomer compositions (SEA) are crosslinkable by polyaddition into self-adhesive state, contain at least one polyorganosiloxane (POS) including sites of ethylenic and/or acetylenic unsaturation {POS containing units ?Si— [unsaturation]}; at least one polyorganosiloxane (POS) containing units ?Si—H; a catalytic system including at least one metal catalyst and at least one crosslinking inhibitor; a filler; at least one adhesion promoter; optionally, at least one POS resin; optionally, at least one thermal resistance agent; and, optionally, at least one other functional additive, and are useful for gluing, assembling, sealing, e.g., joints, coatings, electrical, electronic and automobile engineering parts.

Abstract: The invention relates to adhesive silicone elastomer compositions which can be crosslinked by polyaddition. The composition, crosslinkable by polyaddition (hydrosilylation), comprises: ?/ at least one polyorganosiloxane (POS) bearing ethylenic and/or acetylenic unsaturations [POS with ?Si-(unsaturated) units]; ?/ at least one polyorganosiloxane (POS) with ?Si—H units; ?/ a catalytic combination comprising ?.1 at least one metallic catalyst (preferably platinum based), ?.2 and at least one crosslinking inhibitor; ?/ a filler; ?/ at least one adhesion promoter; ?/ at least one POS resin; ?/ at least one thermal resistance agent; and ?/ optionally at least one other functional additive. Methods of making and using the subject composition are also described.

Abstract: The general field of the invention is that of airbags. The invention relates to a process for improving the tear strength and the combing strength of coated fabrics intended for uses in the field of inflatable bags using a silicone composition comprising an additive containing a polyorganosiloxane resin (V) and a calcium carbonate. After coating the composition onto the fabric supports and curing, the coated supports not only have optimum adhesion and crease resistance properties, but also have good properties in terms of combing strength and tear strength.

Abstract: The invention concerns crosslinkable liquid silicone compositions whereof the inorganic filler can be increased while observing limits of viscosity compatible with coating of woven or nonwoven supports on an industrial scale, and which impart to the supports thermal properties (reducing calorific power and fire-proofing), impermeability and good mechanical characteristics. To achieve this, a mineral compound is used based on zirconium (zirconia or zirconium silicate) as filler slightly thickening ChZr in a crosslinkable liquid silicone composition. The ChZr has a D; ranging between 3 and 15 m and is used in a proportion of 100 to 350 parts by weight for 100 parts by weight of the silicone composition without fillers. Said silicone compositions may be of the type crosslinkable by polyaddition or polycondensation. The invention is useful for silicone coating textile tarpaulins for indoor or outdoor structures.

Abstract: A process for increasing the surface tension (“wettability”) of a silicone element crosslinked by polyaddition from a liquid composition containing one or more ?,?-dimethylvinylpolydimethylsiloxanes (PDMS), one or more poly(dimethyl)(methylhydrogenosiloxy)-?,?-dimethylhydrogenosiloxanes, and a platinum crosslinking catalyst. The silicone surface is treated with a homogeneous atmospheric plasma using a plasma spraying apparatus having a rotating head with one or more plasma nozzles that are offset relative to the axis of rotation, each one being capable of generating a plasma jet whose axis is parallel to said axis of rotation. The articles to which the invention relate include composites of flexible substrate (e.g. textile)/silicone coating. Application: adhesive bonding of silicone surfaces crosslinked by ?Si—H/?Si-vinyl polyaddition.

Abstract: The invention concerns the use as additive for improving properties of resistance to arc tracking and arc erosion: of a mixture A, B or C formed by: concerning mixture A: A1: platinum; and A2: at least an inorganic compound A2.1 of a metal with several degrees of oxidation selected from the group formed by V, Cr, Mn, Fe, Co, Ni, and Cu, in which the metal atom is at a degree of oxidation higher than zero, the least possible (abbreviation: DOX mini); or A3: a combination of at least an inorganic compound A2.1 with at least an inorganic compound A2.2 in which the atom of V, Cr, Mn, Fe, Co, Ni or Cu is at a degree of oxidation higher than DOX mini; concerning mixture B: B1 platinum; and B2: at least an inorganic compound B2.1 of cerium-IV or of lanthanum-III; or B3: a combination of at least an inorganic compound B2.1 with at least an inorganic compound B2.

Abstract: The invention concerns the preparation of a silica suspension in a silicon fluid, said suspension being used to produce silicon vulcanisable by polyaddition (RTV elastomers). The problem which the invention aims to solve is that of finding a technical compromise between the rheological and mechanical properties of the final RTV. The invention solves the problem by providing a method for preparing a silica suspension treated with hexamethyldisilazane (HMDZ) in a silicon fluid with siloxyl Si-Vinyl function, characterized in that it consists essentially in introducing HMDZ in the preparation medium, before and/or substantially while bringing at least part of the silicon fluid prepared with at least part of the particulate filler used, said introduction being carried out once or several times for a HMDZ fraction corresponding to a proportion not more than 8% by dry weight with respect to the total silica charge and after bringing together the POS and the filler.

Abstract: The invention relates to the adhesive bonding of fibrous materials, in particular of flexible supports, such as woven supports or nonwoven supports, comprising at least one silicone coating obtained by the application of a coat or by impregnation. The aim of the invention is to provide an improved process for combining together fiber/silicone composite parts using a silicone elastomer, which process has to be economical and not very expensive to carry out. This aim is achieved by the invention, which relates to a process for the adhesive bonding of fibrous supports, this process being of the type of those consisting in causing the supports to be adhesively bonded to overlap one another, a silicone-based adhesive thermosetting by radical crosslinking using at least one peroxide being inserted between the supports over at least a portion of the region of overlap.

Abstract: The invention concerns a silicone composition crosslinkable into elastomer by hydrosilylation, in the presence of carbene-based metal catalysts. The invention aims at providing a composition of that type, stable over long periods at room temperature (one day to several months), without loss of its characteristic of being heat-curable by hydrosilylation and without generating secondary isomerization or coloring reactions. The invention is characterised in that the composition comprises: a polyorganovinylsiloxane(polydimethyl)(methylvinyl) siloxane; a polyorganohydrogenosiloxane; a platinum catalyst formed by a complex of formula C3 and optionally an acetylene crosslinking inhibitor, optionally a siliceous filler. The invention also concerns novel hydrosilylation catalysts of the metal complex type of formula C3 above.

Abstract: A silicone composition useful especially for the production of varnishes applicable to substrates whose coefficient of friction it is sought to reduce. The object is to provide an anti-friction silicone varnish for textiles coated with silicone elastomers which is economic and adhesive, provides the desired slip, resists soiling and is shiny. This object is achieved by a crosslinkable silicone composition containing two silicones A and B which react with one another in the presence of a catalyst C to allow crosslinking, and a particulate component D selected from the group comprising powdered (co)polyamides—preferably (co)polyamides 6, 12 and 6/12. The (co)polyamide particles are of substantially rounded shape and the mean particle diameter ?md is between 0.1 and 200 ?m, preferably between 5 and 100 ?m and particularly preferably between 10 and 50 ?m. Also disclosed is a varnishing process and a composite containing the varnished substrate.

Abstract: A non-drip, preferably self-adhesive, silicone elastomer composition crosslinkable by polyaddition, such as those polyorganosilanes (POS) bearing C2?C6?Si-alkenyl units and ?Si—H units but excluding fluorinated POS. The composition includes at least a thixotropic additive containing at least a fluorinated resin, preferably based on polyfluoroethylene (PTFE). The composition may be prepared from a Si—Vi polydimethylsiloxane (PDMS) and a Si—H PDMS crosslinked by platinum catalysis. Polytetrafluorethylene, a filler, particularly one containing silicone, optionally a ternary adherence promoter such as vinyltrimethosilane/glycidoxypropyltrimethoxysilane/butyl orthotitanate, and other typical additives may be added to the composition. The composition (not excluding the fluorinated POS as a possible constituent in the composition) may be used to produce joints in situ and/or as an adhesive, particularly in upholstery.

Abstract: The invention relates to the preparation of a suspension of precipitated silica in a silicone oil, this suspension being usable for the production of silicones crosslinkable by polyaddition or polycondensation (RTV elastomers). The object of the invention is to seek a compromise between on the one hand the cost and on the other hand the rheology and mechanical properties of the final RTVs. The invention achieves this object by providing a process for the preparation of a suspension of precipitated silica, treated with hexamethyldisilazane (HMDZ), in a crosslinkable silicone oil. This HMDZ is introduced in at least two fractions. The 1st fraction on the one hand corresponds to a proportion less than or equal to 15% by dry weight, based on the total amount of HMDZ, and on the other hand is first brought into contact with the precipitated silica and the water. The invention further relates to the production of a silicone elastomer composition from this suspension and to the composition thus obtained.

Abstract: A process for increasing the surface tension (“wettability”) of a silicone element crosslinked by polyaddition from a liquid composition containing one or more ?, ?-dimethylvinylpolydimethylsiloxanes (PDMS), one or more poly(dimethyl) (methylhydrogenosiloxy)-?,?-dimethylhydrogenosiloxanes, and a platinum crosslinking catalyst. The silicone surface is treated with a homogeneous atmospheric plasma using a plasma spraying apparatus having a rotating head with one or more plasma nozzles that are offset relative to the axis of rotation, each one being capable of generating a plasma jet whose axis is parallel to said axis of rotation. The articles to which the invention relate include composites of flexible substrate (e.g. textile)/silicone coating. Application: adhesive bonding of silicone surfaces crosslinked by ?Si—H/?Si-vinyl polyaddition.

Abstract: A hydrosilylation (polyaddition)-vulcanizing elastomer silicone composition, including (a) a vinylated polyorganosiloxane (POS), (b) at least one hydrogenated POS, (c) a platinum catalyst, (d) optionally a coupling agent, (e) optionally a mineral filler, (f) optionally a crosslinking inhibitor, and optionally a POS resin and functional additives. The composition has a dynamic viscosity between 1,000 and 7,000 mPa·s, at 25° C. before crosslinking and, after overall crosslinking by thermal effect has at least one of the following properties: a Shore A hardness of at least 2, a breaking strength of at least 0.5 N·mm?1, and a breaking elongation of at least 50%. Also disclosed is a composite which is fully impregnated by means of a 100% bicomponent (RTV-2) silicone liquid.

Abstract: The invention relates to adhesive silicone elastomer compositions which can be crosslinked by polyaddition. The composition, crosslinkable by polyaddition (hydrosilylation), comprises: ?/ at least one polyorganosiloxane (POS) bearing ethylenic and/or acetylenic unsaturations [POS with?Si-(unsaturated) units]; ?/ at least one polyorganosiloxane (POS) with ?Si—H units; ?/ a catalytic combination comprising ?.1 at least one metallic catalyst (preferably platinum based), ?.2 and at least one crosslinking inhibitor; ?/ a filler; ?/ at least one adhesion promoter; ?/ at least one POS resin; ?/ at least one thermal resistance agent; and ?/ optionally at least one other functional additive. Methods of making and using the subject composition are also described.

Abstract: A process for production of an assembly including several silicone elements crosslinked by polyaddition of ?Si—H units onto ?Si-alkenyl (preferably ?Si-vinyl) units, the elements adhering to one another without detracting from their mechanical properties. The process includes: (I) forming (1st coating) a silicone element (i) with a liquid silicone preparation (i) containing polyorganosiloxanes (POS) A with ?Si-vinyl units, (POS) B with ?Si—H units, a platinum catalyst C; (II) crosslinking so that (i) has a surface density SD of unreacted, residual vinyl, per nm2, of 0.0100?SD?0.0040; (III) optionally repeating steps (I) and (II) n times to give n elements (i) that adhere to one another; (IV) forming (2nd coating) a silicone element (ii) with a liquid silicone preparation (ii) of the same type as described above; (v) crosslinking to give crosslinked (ii) that adheres to (i).

Abstract: The invention concerns crosslinkable liquid silicone compositions whereof the inorganic filler can be increased while observing limits of viscosity compatible with coating of woven or nonwoven supports on an industrial scale, and which impart to the supports thermal properties (reducing calorific power and fire-proofing), impermeability and good mechanical characteristics. To achieve this, a mineral compound is used based on zirconium (zirconia or zirconium silicate) as filler slightly thickening ChZr in a crosslinkable liquid silicone composition. The ChZr has a D; ranging between 3 and 15 m and is used in a proportion of 100 to 350 parts by weight for 100 parts by weight of the silicone composition without fillers. Said silicone compositions may be of the type crosslinkable by polyaddition or polycondensation. The invention is useful for silicone coating textile tarpaulins for indoor or outdoor structures.