1. Hydrogen-containing silicone oils typically require emulsification, catalysis, specific formulation, and alkaline conditions within the substrate to function effectively.
2. Silicone oils that are not properly formulated may fail to wet the concrete uniformly or penetrate deeply.
3. Factors such as emulsion particle size, solids content, and stability can influence penetration and surface residue.
4. The reaction within the formulation may release gas; therefore, it is necessary to assess construction safety as well as the impact on porosity and surface appearance.
5. Surface impregnation serves a different purpose than incorporating additives into cement-based product formulations; consequently, the same dosage rates and acceptance criteria cannot be applied to both.
Therefore, when on-site spraying is required and penetration depth is a priority, specialized silane or silane-siloxane systems should be evaluated first; conversely, when bulk water repellency is required for cement or gypsum products, suitable hydrogen-containing silicone oil emulsions or other internal additive systems should be considered.