How to choose defoaming agent?

In general, an effective defoamer must satisfy the following conditions:

• Must have a higher surface activity than a foaming surfactant, i.e. it must have a lower surface tension.

• Easy to disperse in a system

• It must be insoluble (at least partially insoluble) in the foaming medium, or it will act as a surfactant itself, i.e. to stabilize the foam.

• The droplet size of the defoamer should be within the thickness range of the foam thin layer.

• Chemical inertia

• No residue or odor