Foam control compositions comprising silicone materials

A process for making a foam control composition comprising a silicone material in which is dispersed a finely divided filler, which comprises the steps of:

• A) providing for a silicone based material cured via a condensation cure chemistry which is the condensation reaction product of:
• (i) at least one condensation curable silyl terminated polymer having at least one hydrolysable and/or hydroxyl functional groups per molecule;
• (ii) a cross-linker selected from silanes having at least 2 hydrolysable groups and/or polysilanes having at least 2 hydrolysable groups and/or polysilyl functional molecules having at least 2 silyl groups, each silyl group containing at least one hydrolysable group;
• and
• (iii) a condensation catalyst selected from the group of titanates or zirconates characterized in that the molar ratio of hydroxyl groups to hydrolysable groups is between 0.5:1 to 2:1 using a monosilane cross linker or 0.5:1 to 6:1 using disilyl functional crosslinker and the molar ratio of M-OR functions to the hydroxyl groups is comprised between 0.01:1 and 0.5:1, where M is titanium or zirconium;
• and subsequently:
• B) mixing the finely divided filler (b) in the silicone based material cured via a condensation cure chemistry.

A process for making a foam control composition comprising a silicone material in which is dispersed a finely divided filler, which comprises the steps of:

• A) mixing prior to step (B) a finely divided filler (b) with
• (i) at least one condensation curable silyl terminated polymer having at least one hydrolysable and/or hydroxyl functional groups per molecule;
• (ii) a cross-linker selected from silanes having at least 2 hydrolysable groups and/or polysilanes having at least 2 hydrolysable groups and/or polysilyl functional molecules having at least 2 silyl groups, each silyl group containing at least one hydrolysable group;
• and
• (iii) a condensation catalyst selected from the group of titanates or zirconates characterized in that the molar ratio of hydroxyl groups to hydrolysable groups is between 0.5:1 to 2:1 using a monosilane cross linker or 0.5:1 to 6:1 using disilyl functional crosslinker and the molar ratio of M-OR functions to the hydroxyl groups is comprised between 0.01:1 and 0.5:1, where M is titanium or zirconium;
• and subsequently
• B) allowing the condensation reaction of components (i) and (ii) in the presence of the condensation catalyst (iii) and finely divided filler (b).

A process for making a foam control composition comprising a silicone material in which is dispersed a finely divided filler, which comprises the steps of:

• A) providing for a silicone based material cured via a condensation cure chemistry which is the condensation reaction product of:
• (i) at least one condensation curable silyl terminated polymer having at least one hydrolysable and/or hydroxyl functional groups per molecule;
• (ii) a cross-linker selected from silanes having at least 2 hydrolysable groups and/or polysilanes having at least 2 hydrolysable groups and/or polysilyl functional molecules having at least 2 silyl groups, each silyl group containing at least one hydrolysable group;
• and
• (iii) a condensation catalyst selected from the group of titanates or zirconates characterized in that the molar ratio of hydroxyl groups to hydrolysable groups is between 0.5:1 to 2:1 using a monosilane cross linker or 0.5:1 to 6:1 using disilyl functional crosslinker and the molar ratio of M-OR functions to the hydroxyl groups is comprised between 0.01:1 and 0.5:1, where M is titanium or zirconium;
• and subsequently
• B) mixing the finely divided filler in the silicone based material cured via a condensation cure chemistry;
• and subsequently
• C) emulsifying the mixture of step B).