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CAB-O-SIL® S-17D, the highest surface area fumed silica available, imparts the highest reinforcement in rubbers. The bulk density of S-17D has been mechanically increased for faster incorporation and ease of handling. 

Application Information:

CAB-O-SIL S-17D is used to reinforce silicone rubbers.  Use of densed, higher bulk density, silica such as S-17D requires very high shear dispersion equipment to achieve adequate dispersion of the silica.  The higher bulk density of S-17D facilitates faster wet-in or incorporation into these viscous polymer systems.

Silicone Rubbers:

CAB-O-SIL S-17D is widely used for reinforcement of liquid silicone rubbers (LSR).  It imparts the greatest increase in hardness, tensile and elongation.  For clear silicone rubber applications, very well dispersed S-17D provides the greatest transparency.  Because of the hydrophilic surface of untreated fumed silicas, further modification of the silica surface is necessary to prevent crepe hardening.