SiSiB® PC2000 is a bifunctional polysulfidic organosilane for the rubber industry defined chemically as Bis(3-triethoxysilylpropyl)tetrasulfide. It is used to improve the reinforcing capability of fillers with silanol group on their surface (e.g., silicas, silicates, clay, etc.), and also as an integral part of curing systems to improve crosslinking network properties.
SiSiB® PC2000 is the equivalent of Momentive's A-1289, Dow's Z-6940, Evonik's Si-69, ShinEtsu's KBE-846 silane.
Color and Appearance
1.1 +/- 0.02
Boiling Point at 1013 mbar(°C)
Decomposition above 250
Flash Point (°C)
Average Chain Length(%)
3.75 +/- 0.15
Total Sulfur (standard value)(%)
22.7 +/- 0.8
Soluble in Primary alcohols, ketones, benzene, toluene, dimethylformaminde, chlorinated hydtocarbons, cetonitrile, dimethysulfoxide; Insoluble in Water;
When used in rubber compounds, it produces these effects:
Silane coupling agent for non-black pigments.
Cure equilibrium for reversion resistance.
Curing agent for good heat aging.
Coupling Agent - With as little as 0.5 to 1.0 phr with clay fillers and 1.0 to 4.0 phr for silica pigments, SiSiB® PC2000 couples the non-black pigment and elastomers resulting in increases in modulus of low modulus silicone and increase in abrasion resistance.
Cure Equilibrium - SiSiB® PC2000 has four sulfur atoms positioned in the center.
At cure temperatures, these participate with sulfur in producing polysulfidic crosslinks. The SiSiB® PC2000 replaces crosslinks broken during cure, resulting in reversion resistant, and with proper compounding, reversion free compounds. This is known as equilibrium cure. The dynamic flex characteristics, E.G., heat generation and crack growth, are dramatically improved.
Curing Agent - Removing all sulfur from the compound for NR, SBR, NBR and replacing it with SiSiB® PC2000 and certain thiuram accelerators, produces compounds with excellent heat aging characteristics in addition to the coupling effects.
SiSiB® PC2000 is a silane coupling agent that has crosslinking and accelerator activity in silicone rubber compounds.
SiSiB® PC2000 is supplied in net weight 200Kg steel drum or 1000Kg IBC tote.
In the unopened original container SiSiB® PC2000 has a shelf life of five years in a dry and cool place.