Abstract: A method for hydrolyzing/condensing, by acid catalysis, silanes bearing hydrolyzable groups, preferably halogenosilanes and more preferably still chlorosilanes, in a polyphase reaction medium (preferably biphasic), includes contacting the silanes bearing the hydrolyzable groups with water, buffer solution and neutralizing agent, while stirring, then in separating the aqueous phase from the organic phase, which contains the hydrolysis/condensation products, namely hydroxylated polyorganosiloxanes; such method is characterized by (a) employing intensively stirring means producing, in the reaction medium, an agitation at least equivalent to that induced by a shearing corresponding to that provided by a rotor whereof the peripheral speed is not less than 8 m.s?1, preferably not less than 10 m.s?1, and more preferably still ranging between 15 and 20 m.s?1, enabling thus organic phase droplets to be formed, of d32 less than 500 ?m; and (b) ensuring that the silanes/aqueous phase mass fraction is not less than 0.

Abstract: A method for hydrolyzing/condensing, by acid catalysis, silanes bearing hydrolyzable groups, preferably halogenosilanes and more preferably still chlorosilanes, in a polyphase reaction medium (preferably biphasic), includes contacting the silanes bearing the hydrolyzable groups with water, buffer solution and neutralizing agent, while stirring, then in separating the aqueous phase from the organic phase, which contains the hydrolysis/condensation products, namely hydroxylated polyorganosiloxanes; such method is characterized by (a) employing intensively stirring means producing, in the reaction medium, an agitation at least equivalent to that induced by a shearing corresponding to that provided by a rotor whereof the peripheral speed is not less than 8 m.s?1, preferably not less than 10 m.s1, and more preferably still ranging between 15 and 20 m.s?1, enabling thus organic phase droplets to be formed, of d32 less than 500 ?m; and (b) ensuring that the silanes/aqueous phase mass fraction is not less than 0.

Abstract: The invention concerns the use for increasing the life span of molds made of silicone elastomer crosslinking by polyaddition or polycondensation reaction, of an additive capable of stabilizing the silicone elastomer whereof the mold is constituted with respect to materials to be mouded, said additive corresponding the following formula (1) wherein R1 and R2 are linear or branched alkyl radicals or cycloaliphatic radicals having 1 to 40 carbon atoms. Preferably, said additive is methyl laurylthiopropionate. C12H25—S—CH2—CH2—CO—O—CH3. The invention also concerns the corresponding silicone compositions and the resulting molds.

Abstract: The invention relates to a heat-activated initiator for polymerising and/or cross-linking polyorganosiloxane-type monomers, oligomers and/or polymers with organofunctional groups, comprising a boron derivative of formula (I): (A)xB(R′)y, wherein the symbols R′ are the same or different and represent an alkyl or alkenyl radical in C1-C12, an alkoxy radical in C1-C12, a phenyl radical substituted by at least one electroattractor element, an aryl radical containing at least two aromatic rings such as biphenyl, naphthyl, optionally substituted by at least one electroattractor element, especially a halogen atom (particularly fluorine), or an electroattractor group, especially a CF3, NO2, CN group; and a radical —C2H4—Si(Q)3 with the symbols Q being the same or different and representing an alkyl or alkoxy group in C1 to C10 or a siloxane oligomer with less than 10 silicon atoms. The invention also relates to a corresponding cross-linkable composition and to the uses thereof.

Abstract: The invention relates to polyorganosiloxane polymers to which antioxidant functional groups have been grafted. These polymers can be used for the stabilization of polymer compositions, in particular non-organosilicon organic polymer compositions and silicone compositions. More particularly, they are used to stabilize silicone compositions intended for the preparation of moulds, in particular of moulds for the moulding of polyester items.

Abstract: The invention concerns the use for increasing the life span of moulds made of silicone elastomer crosslinking by polyaddition or polycondensation reaction, of an additive capable of stabilising the silicone elastomer whereof the mould is constituted with respect to materials to be moulded, said additive corresponding the following formula (1) wherein R1 and R2 are linear or branched alkyl radicals or cycloaliphatic radicals having 1 to 40 carbon atoms. Preferably, said additive is methyl laurylthiopropionate. C12H25—S—CH3—CH2—CO—O—CH3. The invention also concerns the corresponding silicone compositions and the resulting moulds.

Abstract: The invention concerns the use as heat-activated catalyst of at least a boron derivative of formula (I): AxB(R)y for dehydrogenative concentration between at least a monomer, oligomer and/or polymer organosiloxane having, per molecule, at least a reactive SiH unit and at least a monomer, oligomer and/or polymer organosiloxane having, per molecule, at least a reactive SiOH unit.