In the world of silica, hydrophobicity is often claimed, but rarely quantified by the metric that matters most: The Contact Angle.
1. What is Contact Angle?
When a water droplet hits a surface, the angle at the interface between the liquid and the solid determines its wettability. Untreated silica has a contact angle of near 0°—it is "thirsty." Most commercial hydrophobic silicas reach 70-90°. At Silfeed, we set our benchmark at ≥110°.
2. The 110° Threshold
Why 110°? This is the tipping point where a surface transitions from "hydrophobic" to "super-hydrophobic characteristics." At 110°, water cannot just "sit"—it must bead. In a feed mill environment where humidity (RH) often exceeds 95%, this angle is the difference between a free-flowing production line and a catastrophic blockage.
High risk of "bridging" in storage silos.
Permanent flow, zero moisture ingress.
3. Precision Manufacturing
Achieving this angle requires absolute uniformity in the molecular grafting process. Our Sanming facility uses a proprietary multi-stage vapor-phase deposition technique, ensuring that every single silica particle—not just the surface layer—is shielded from moisture.