HIFULL®HB-139 Fumed Silica (BET=110㎡/g)

Description

Compared to untreated hydrophilic fumed silica, HB-139 loses its surface hydroxyl groups due to chemical reactions or shielding, making it hydrophobic. Its particle size increases, and the nitrogen adsorption-specific surface area decreases from 200m²/g to around 110±30 m²/g. Its pH ranges from 4.0% to 7.0% in a 4% dispersion of isopropanol-water solution (1:1 volume ratio). The pH change of hydrophobic fumed silica is influenced by the treating agent.

Further Information

How to Use Fumed (Colloidal) Silica

Fumed Silica requires significant agitation (stirring) to become fully mixed into a resin. Use of a mechanical stirrer will make the process quicker and easier but manual mixing is perfectly possible. For maximum effect, allow the Fumed Silica to soak in the resin for as much as a day before thorough mixing. Fumed Silica added to resin at a ratio of 0.7% – 1% (by weight) will produce a thixotropic resin. 2-3% will produce a gelcoat consistency. Percentages up to 3%+ can be used to make a filler paste (additional filler powders may be required). Please note the addition of Fumed Silica will reduce the clarity of clear resin systems meaning it is not ideal for turning clear laminating resin into a clear gelcoat.

Safety

Fumed Silica particles are incredibly small and light and will become airborne as soon as the material is scooped, moved or mixed. Always wear protective gloves and a dust mask when handling this product in its raw state.