[ioannis]

Hi all,
I am having issues in some of my formulations. I am using Aerosil R972 (Silane, dichlorodimethyl-, reaction products with silica) in a paint solvent-bourne system for its anti-settling, anti-sagging and corrosion resistance properties. Lately I observed clusters on the paint surface after the addition of a solution of polymeric phosforic acid ester (DISPERBYK-110) as a wetting and dispersing additive. Is it possible that silica reacts with the phosphoric acid ester to cause silica particle clusters?

Thanks in advance,

Ioannis

[Hunter2]

I would say yes. Wetting means it has hydrophobic groups, which easily react with silan compounds.