Thixotropic additive for RTV-2 silicones

General Information

SI-661, when used in specific Silicones, Inc. RTV-2 silicones, creates a non-flowing (thixotropic) version. It is recommended where there is an extreme vertical surface, such as walls or natural objects, for on-site architectural reproductions, and to enable cost effective glove molding of irregularly shaped items. The addition of SI-661 allows the silicone rubber to be applied with a brush, spatula or trowel. It can be used in a variety of silicones, such as GI-1000, GI-384, P-10, P-15, P-20, P-90, P-45, P-727 and P-830, in amounts varying from 0.1 to 5 % by weight depending on the product. Mix the silicone rubber according to normal directions and add the SI-661 once a homogeneous mixture is achieved. If a skin coat is wanted, first apply the unmodified catalyzed silicone rubber to the original, then immediately follow with a layer of the same rubber containing the SI-661. Allow the silicone rubber to cure normally, usually 16 to 18 hours, before demolding.