Fumed Silica
SemiSIL® hydrophilic and hydrophobic fumed silica grades — BET 100–380 m²/g — for rheology control, mechanical reinforcement, and surface modification across coatings, adhesives, silicone rubber, inks, and pharmaceuticals.
Technical Grade Selection Matrix
Select the optimal hydrophilic or hydrophobic grade based on your resin system’s polarity and viscosity requirements.
| Grade / Model | Surface Property | BET Area (m²/g) | Carbon Content | Recommended Application |
|---|---|---|---|---|
| SEMISIL 150 | Hydrophilic | 150 ± 20 | — | RTV Silicone Rubber, Coatings, PVC |
| SEMISIL 200 | Hydrophilic | 200 ± 20 | — | RTV Silicone, Adhesives, Paints |
| SEMISIL 300 | Hydrophilic | 300 ± 20 | — | HTV Silicone Rubber, Defoamers, Resins |
| SEMISIL 380 | Hydrophilic | 380 ± 20 | — | LSR, Gel Coats, Specialty Greases |
| SEMISIL R110 | Hydrophobic | 100 ± 20 | 3.5 – 5.5% | Moisture-sensitive RTV, Advanced Coatings |
| SEMISIL R272 | Hydrophobic | 110 ± 20 | 0.6 – 1.2% | Printing Inks, Industrial Adhesives |
| SEMISIL R620 | Hydrophobic | 260 ± 30 | 2.8 – 4.0% | Liquid Coatings, Pharmaceutical Excipients |
Industrial Applications
Coatings & Paints
Optimizing surface integrity, adhesion, and suspension stability for high-performance coating systems.
Rheological Precision
Prevents pigment settling and phase separation.
Anti-Sagging
Eliminates paint runoff on vertical surfaces.
Surface Fortification
Enhances scratch resistance and weatherability.
Adhesion Promotion
Strengthens bonding between films and substrates.
Silicone Rubber (HTV / LSR)
Enhancing structural integrity and thermal stability via advanced 3D silica networking.
Molecular Networking
Si-OH groups bond with macromolecules for 3D reinforcement.
Mechanical Boost
Increases base rubber strength up to 40× (tensile / tear).
Dynamic Resilience
Improves hardness while maintaining elasticity.
Thermal Protection
Bolsters heat resistance and dielectric properties.
Printing Inks
Optimises rheology and drying speed for precise imaging on high-speed substrates.
Optical Enhancement
Maximises brightness and colour density.
Dispersion Stability
Controls anti-settling for long storage life.
Precision Rheology
Ensures sharp contours and streak-free flow.
Pharmaceuticals
Enhances solid-dosage consistency and liquid formulation stability.
Improved Flowability
Optimises powder flow for precise manufacturing.
Anti-Adherent Action
Prevents tablet sticking and ensures mould release.
Formulation Stability
Stabilises emulsions and suspensions.
Logistics & Loading Specs
Standardised vacuum packaging (10 kg/bag) designed for maximum freight efficiency.
| Transport Mode | Pallet Configuration | Total Bags (10 kg) | Total Net Weight |
|---|---|---|---|
| Domestic Truck (17.5 m) | Full Truckload (FTL) | 880 Bags | 8.8 Tons |
| 20′ Container (Ocean) | 10 Pallets (180 kg/pallet) | 180 Bags | 1.8 Tons |
| 40′ High Cube | 20 Pallets (220 kg/pallet) | 440 Bags | 4.4 Tons |
| 40′ High Cube (Max Vol) | 20 Pallets + Loose Bags | 480 Bags | 4.8 Tons |
Global Delivery Lead Times
| Milestone | Timeline |
|---|---|
| Port Preparation | Ready at Qingdao Port within 3 days |
| Total Origin Lead Time | Order confirmation to departure: 3–7 days |
| SE Asia Frequency | 3–4 departures per week |
| EU / Middle East Frequency | 1 departure per week |
Fumed Silica in Lithium Battery
SEMITECH fumed silica plays two distinct roles in the lithium battery cell — controlling the rheology of separator coating slurries and enabling gel polymer electrolyte formation. Both rely on its hydrogen-bond-driven thixotropic gel behaviour in polar solvents.
Frequently Asked Questions
+How to choose between Hydrophilic and Hydrophobic silica?
Use hydrophilic silica for polar systems and hydrophobic silica for non-polar systems. Hydrophilic grades provide maximum thickening through hydrogen bonding in polar media (like water-borne coatings). Hydrophobic grades (e.g., SEMISIL R620) are surface-treated to contain a carbon content of 0.6–5.5%, making them essential in moisture-sensitive formulations like epoxy or silicone resins to prevent viscosity drift.
+What is the optimal dosage for anti-sagging?
Typically 0.5% to 2.0% by total weight. At this concentration, the particles form a stable 3D thixotropic network that counteracts gravity on vertical surfaces.
+How much can it increase silicone rubber tensile strength?
Up to 40 times. By utilising grades with a BET surface area of 300 ± 20 m²/g, the Si-OH groups create dense molecular cross-linking with raw silicone macromolecules.
+What impact does BET surface area have on dispersion energy?
Higher BET surface area directly increases the required dispersion energy. High surface area grades (e.g., 380 m²/g) require high-shear equipment operating at a peripheral speed of 10–15 m/s to fully develop the rheological network.