Two-part condensation curable silicone compositions and their applications are provided. Also provided is a new titanium-based reaction product, which, because of its incorporation as a catalyst, is able to provide compositions having both improved stability in the presence of water and accelerated cure processes when compared to conventional titanium catalysts. The titanium-based reaction product is obtained or obtainable from a process comprising the steps of: (i) mixing a first ingredient, an alkoxy titanium compound having from 2 to 4 alkoxy groups with a second ingredient, a linear or branched polydiorganosiloxane polymer having at least two terminal silanol groups per molecule; (ii) enabling the first and second ingredients to react together by stirring under vacuum to form a reaction product; and collecting the reaction product of step (ii).

This silicone gel composition contains (A) an organopolysiloxane having one or more silicon atom-bonded alkenyl groups per molecule, (B) an organohydrogen polysiloxane having two or more silicon atom-bonded hydrogen atoms per molecule, (C) a platinum group metal-based curing catalyst, (D) an isocyanuric acid derivative having two trialkoxysilyl groups and one crosslinkable vinyl group and/or an isocyanuric acid derivative having three trialkoxysilyl groups, and (E) a ketenesilylacetal-type compound, and provides a cured product having a specific penetration.

The silicone gel composition can provide a silicone gel cured product that is a silicone gel having excellent heat resistance and adhesiveness to metals at high temperature and having a high penetration, that is capable of maintaining a low elastic modulus and a low stress even in use at high temperature for long periods of time, and that enables reduction of the occurrence of bubbles and reduction of deterioration in releasability from a substrate and in electrical insulating properties.

An alkoxysilane is contacted with water and an inorganic acid to form a first composition. A zirconium alkoxide is contacted with an organic acid to form a second composition. One or more alkoxysilanes and an organic acid are contacted with a mixture of the first and second compositions to form a sol-gel composition, to which a photoinitiator is added. The sol-gel composition has a ratio of a number of moles of silicon to a number of moles of zirconium (n.sub.Si/n.sub.Zr) ranging from about 2 to about 10. The sol-gel composition is applied on a substrate (e.g., an aluminum alloy substrate) multiple times to form multiple sol-gel layers, and at least one of the sol-gel layers is cured by UV radiation. The multiple sol-gel layers are then thermally cured.

An alkoxysilane is contacted with water and an inorganic acid to form a first composition. A zirconium alkoxide is contacted with an organic acid to form a second composition. One or more alkoxysilanes and an organic acid are contacted with a mixture of the first and second compositions to form a sol-gel composition, to which a photoinitiator is added. The sol-gel composition has a ratio of a number of moles of silicon to a number of moles of zirconium (n.sub.Si/n.sub.Zr) ranging from about 2 to about 10. The sol-gel composition is applied on a substrate (e.g., an aluminum alloy substrate) multiple times to form multiple sol-gel layers, and at least one of the sol-gel layers is cured by UV radiation. The multiple sol-gel layers are then thermally cured.

[Problem] To provide a curable white silicone composition that is capable of forming a cured product having a high optical reflectance as well as exceptional light resistance.

[Solution] The above-mentioned problem is solved by a curable white silicone composition comprising (A) an organopolysiloxane having at least 2 alkenyl groups per molecule, (B) a cerium-containing organopolysiloxane, (C) a white pigment, and (D) a curing catalyst.

A method for manufacturing a water-based coating material is provided, including: (a) reacting tetraalkoxysilane, acidic aqueous solution of vanadium salt, and trialkoxyalkylsilane to form an oligomer; (b) reacting the oligomer with colloidal silica particles to form a modified oligomer; and (c) reacting the modified oligomer with trialkoxyepoxysilane to obtain a water-based coating material.

An adhesive for joining metals and resins is disclosed. The adhesive comprises 0.0001˜3 wt. % of amino silane, 0.0001˜1 wt. % of a crosslinker and 0.0001˜3 wt. % of an organometallic compound. In particular, the adhesive forms an adhesive layer that has a metal atomic ratio less than 50%.

Aqueous silicone emulsion compositions which cure utilising titanium-based reaction products as catalysts, and a process to prepare the same and their uses, are provided. The composition comprises (a) a titanium-based reaction product; (b) one or more silicon containing compounds having at least 2 or at least 3 hydroxyl and/or hydrolysable groups per molecule; (c) one or more surfactants; and (d) water. The titanium-based reaction product (a) is obtained or obtainable from a process comprising the steps of: (i) mixing a first ingredient, an alkoxy titanium compound having from 2 to 4 alkoxy groups with a second ingredient, a linear or branched polydiorganosiloxane having at least two terminal silanol groups per molecule and a viscosity of from 30 to 300,000 mPa.Math.s at 25 C.; (ii) enabling the first and second ingredients to react together by stirring under vacuum to form a reaction product; and (iii) collecting the reaction product of step (ii).

Aqueous silicone emulsion compositions which cure utilising titanium-based reaction products as catalysts, and a process to prepare the same and their uses, are provided. The composition comprises (a) a titanium-based reaction product; (b) one or more silicon containing compounds having at least 2 or at least 3 hydroxyl and/or hydrolysable groups per molecule; (c) one or more surfactants; and (d) water. The titanium-based reaction product (a) is obtained or obtainable from a process comprising the steps of: (i) mixing a first ingredient, an alkoxy titanium compound having from 2 to 4 alkoxy groups with a second ingredient, a linear or branched polydiorganosiloxane having at least two terminal silanol groups per molecule and a viscosity of from 30 to 300,000 mPa.Math.s at 25 C.; (ii) enabling the first and second ingredients to react together by stirring under vacuum to form a reaction product; and (iii) collecting the reaction product of step (ii).

A process for the preparation of a titanium-based reaction product is provided. The titanium-based reaction product comprises the reaction product of an alkoxy titanium compound and a silanol terminated polydiorganosiloxane. The polydiorganosiloxane typically has at least two silanol groups per molecule. The titanium-based reaction product is also described, as is its use as a catalyst, having improved stability in the presence of water, for condensation curable silicone compositions. The titanium-based reaction product may additionally at least partially replace the need for a separate polymer to be used in the condensation curable silicone compositions.