Mixtures of polydiorganosiloxanes - and silica of specified properties are anti-foaming agents

摘要

These are based on mixtures of siloxane polymers and silica. Viscosity at 25 deg.C is 50-500.000 cs, and 1-10% consists of silicon with a surface of at least 50 m2/g and a liquid consisting essentially of a polydiorganosiloxane, in which the organic groups are methyl and/or ethyl and/or 2-phenylpropyl.