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3.3.2Defoamer formulations
ОглавлениеCombinations of the active ingredients described above are frequently used in defoamers. This enables properties such as effectiveness against macro-foam and micro-foam or compatibility with the application system to be varied as required. Filling with a hydrophobic particle often boosts efficiency significantly [3]. Defoamers are supplied in different forms: concentrates, emulsions or solutions. The properties of the different supply forms are indicated in Table 3.2.
| Table 3.2: Comparison of supply forms of defoamers | |||
| Concentrates | Emulsions | Solutions | |
| Active content | 100 % | 10 – 25 % | ≤ 60 % |
| Filled with hydrophobic particles | mostly | mostly | rarely |
| Solvent-free | yes | yes | no |
| Dilutability | good | limited | very good |
| Storage stability | long | limited | long |
| Freeze stability | yes | no | yes |
| Incorporation | requires high shear forces | easy | easy |
| Efficiency | very high | high | moderate |
| Compatibility | in some systems critical | good | very good |
