Overview
HJSIL R622 is a hydrophobic fumed silica treated with HMDS (hexamethyldisilazane), supplied as a high-purity white colloidal powder with a BET surface area of 260 ± 30 m²/g. Its high specific surface area and strong hydrophobicity make it an excellent reinforcing filler for HTV and liquid silicone rubber, while also delivering stable thixotropy and anti-caking performance in coatings, inks, adhesives, sealants, and powder coatings. Equivalent to Aerosil R812.
Technical Specifications
| Property | Unit | Value | Standard |
|---|---|---|---|
| Specific surface area (BET) | m²/g | 260 ± 30 | GB/T20020 |
| pH value (4% dispersion) | — | 5.5–7.8 | GB/T20020 |
| Loss on drying (105°C, 2 hrs) | Wt% | ≤0.5 | GB/T20020 |
| Loss on ignition (1000°C, 2 hrs) | Wt% | ≤4.0 | GB/T20020 |
| Silica content | Wt% | ≥99.8 | GB/T20020 |
| Tamped density | g/L | 40–60 | GB/T20020 |
| Carbon content | Wt% | 2.8–4.0 | GB/T20020 |
| Surface treatment | — | HMDS (hexamethyldisilazane) | — |
| Appearance | — | Lightweight, fluffy white powder | — |
Applications
- HTV silicone rubber reinforcement
- Liquid silicone rubber
- Adhesives and sealants
- Paints and coatings
- Printing inks
- Powder coatings
Key Properties
- Reinforcement of HTV silicone rubber with excellent anti-caking performance
- High hydrophobicity and stable thixotropy for coatings and inks
- Good hydrophobic and rheology performance in adhesives and sealants
- Improvement of free flow in powder coatings and anti-caking
Packaging & Storage
Supplied in 10 kg kraft paper bags. Store in closed containers under dry conditions and protect from volatile substances.
Lead time: 10 days.
Related Products
- HJSIL® Fumed Silica
- HJSIL R620 — HMDS-treated hydrophobic fumed silica, 190 m²/g BET
- HJSIL R272 — DDS-treated hydrophobic fumed silica, 110 m²/g BET
- HJSIL R110 — PDMS-treated hydrophobic fumed silica, 100 m²/g BET
Next step
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