AEROSIL® R 972

Description

AEROSIL® fumed silica such as hydrophilic AEROSIL® 150 is used as a thickening and reinforcing thixotropic filler in silicone sealants. These hydrophilic fumed silica products have freely accessible silanol groups (Si-OH) on their surface causing moisture absorption from environment. However, moisture absorption reduces the shelf-life of the silicone sealants, especially of moisture sensitive neutral alkoxy formulations. Hydrophobization with DDS eliminates the silanol groups and turns the hydrophilic surface of the fumed silica to hydrophobic, for example in AEROSIL® R 972.

Hydrophobized fumed silica powder

BET Surface area: 90 – 130 m2/g

Carbon content: 0.6 – 1.2 %

Key effects: rheology, reinforcement, anti-settling, free-flow, anti-caking

Typical applications: silicone rubber and sealants, adhesives, cosmetics, plant care, coatings

BENEFITS & ADVANTAGES
• Hydrophobic component for thickening and reinforcement of RTV-1 K silicone sealants
• Improves shelf-life of silicone sealants
• Water resistant, hydrophobising of liquid systems
• Rheology control of (complex) liquid systems
• For use in coatings as anti-settling agent, for pigment stablilization and improvement of corrosion protection
• Improves hydrophobicity and rheology of offset printing inks
• Improvement and maintenance of free flow and anticaking characteristics of powders