Henkel Hysol Loctite® UA5529-B80 Polyurethane Resin, 225.6 °C Flash Point, 85 Shore A Hardness, Musty Odor/Scent, 1.24 At 25 °C Specific Gravity. LOCTITE® STYCAST US 5529 is a flexible, flame retardant, mineral filled, polyurethane compound. This potting compound has long pot life, and is low viscosity so it flows well and adheres well to many substrates. It has very low odor and does not contain TDI or mercury compounds. Although LOCTITE STYCAST US 5529 is not UL recognized, it does have the same amount of flame retardant chemical as US5528, which is UL recognized.