Description

Aerosil R 202 is a hydrophobic fumed silica, a high-performance specialty chemical widely used as a rheology control agent and reinforcing filler. Its surface-treated, hydrophobic nature provides excellent thickening, anti-settling, and free-flowing properties in demanding formulations. This product is essential for manufacturers in the coatings, adhesives, sealants, and elastomers (CASE) industries, as well as in plastics and personal care, seeking to enhance product stability and performance.

Application

• Rheology Modifier in Coatings & Inks: Provides sag resistance, anti-settling, and improved application properties in solvent-based and high-solids systems.
• Reinforcing Filler in Silicone Sealants & Elastomers: Enhances tensile strength, tear resistance, and thixotropy without interfering with cure chemistry.
• Anti-caking and Free-flow Agent: Prevents caking and ensures consistent flow in powders, including construction chemicals and food-contact materials where hydrophobicity is required.
• Viscosity Control in Adhesives: Imparts thixotropy to prevent slump in vertical applications and controls penetration in porous substrates.
• Gelation and Thickening Agent: Used in greases, gel coats, and resin systems to create stable, non-sagging gels.
• Plastics and Composites: Acts as a processing aid and reinforcing agent to improve mechanical properties and dispersion.

Basic Information

Product Name	Aerosil R 202
CAS No.	109944-58-3
Molecular Formula	SiO₂ · (C₈H₁₇)ₓ (Surface modified)
Molecular Weight	N/A (Polymeric material)
Synonyms	Hydrophobic Fumed Silica; Silica, dimethylsilylated; Octylsilane-treated silica; Fumed silica, hydrophobic grade; Pyrogenic silica, surface-treated; R 202; Colloidal silicon dioxide, hydrophobic; CAB-O-SIL TS-720 (similar type)
EINECS	Contact for details

Quality Control

Our Aerosil R 202 is manufactured under a stringent quality management system. Each batch is tested against rigorous internal specifications to ensure consistent performance as a rheological additive. Key parameters such as hydrophobicity, specific surface area (BET), and tamped density are verified. A Certificate of Analysis (COA) documenting these results is available for every shipment to support your quality assurance and regulatory compliance needs.

Storage

Preserve in a tightly closed container, protected from light. This product is hygroscopic (moisture-sensitive). Store in a cool, dry, and well-ventilated area at room temperature (15-25°C). Keep the container tightly sealed when not in use to prevent moisture absorption, which can affect performance. Keep away from strong acids and bases.

Specification

Item	Specification
Appearance	White, fluffy powder
Hydrophobicity	Hydrophobic (Surface modified)
Specific Surface Area (BET)	90 - 130 m²/g
Tamped Density	Approx. 50 g/l
pH (in 4% dispersion)	4.0 - 6.0
Loss on Drying (2h @ 105°C)	≤ 1.0 %
Ignition Loss (2h @ 1000°C)	2.0 - 5.0 %
Sieve Residue (Mocker, 45 µm)	≤ 0.05 %

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.