Ultra "Tiecoat" allows the adhesion of unsaturated polyester gelcoats to epoxy laminating resins.

The coating, catalyzed with 1.5 to 2.5 percent MEKP, is applied at 15 to 20 mils and allowed to cure for two to three hours at a minimum temperature of 70ºF (21ºC) prior to laminating with epoxy resin.

In addition to meeting the ASTM D 790 standard for bond strength, the tiecoat increases film toughness and water osmosis resistance while decreasing fiber pattern and print-through.

At 77ºF (25ºC), the uncured coating has a viscosity of 2,000-9,000 cps and gel time of eight to 12 minutes (1.5 percent MEKP). Peak exotherm is 300º to 366ºF (149º to 186ºC). The cured coating exhibits 3.5 percent flexural elongation and 300°F (149°C) heat distortion temperature.