Rheology characterization of UV curable silicone elastomers

摘要

Silicone rubber is vulcanized through either addition cure, condensation cure or free radical cure. Addition-cured silicone generally offers better mechanical, electrical and optical properties than other silicones. Platinum is a commonly used catalyst for addition cure. It is normally activated by heat to facilitate the hydrosilylation reaction between vinyl containing polysiloxane and hydride containing polysiloxane that crosslinks the rubber (refs. 1 and 2). Typical curing temperatures for fabricating silicone articles are in the range of 120-200°C. Such high temperatures tend to exclude silicone from consideration in many applications involving low heat materials (such as polyolefins) or temperature-sensitive substances (such as pharmaceutical ingredients). It is also challenging to find a desired balance of fast cure and long work life for silicone, which are two seemingly contradictory but important properties.