Rheology Characterization of UV Curable Silicone Elastomers

Vulcanization using UV light makes it possible for command cure of silicone rubbers.  It combines fast cure with long work life, two counter-intuitive properties for most heat-cured or moisture-cured silicones.  It also can help solve some long-standing processing challenges for conventional silicones, such as making thick parts or integrating temperature-sensitive materials.  However, characterizing the vulcanization behavior of UV curable silicones is not an easy task, as UV radiation has to be implemented in the test.  Dynamic rheology is utilized in this study to investigate the curing properties of UV curable silicone.  The effect of UV intensity, catalyst loading, sample thickness and irradiation time on the curing is also examined.  Rheology is an important tool that not only helps define the vulcanization process but also helps elucidate and quantify the curing features of this new class of silicone elastomers.