Bismaleimide Resin BMI-70

BMI-70 cured coatings retain structural integrity and electrical insulation properties from –60°C to +250°C continuous service, with short-term excursion resistance to 300°C. This is achieved through the thermally stable imide ring structure forming during ring-opening polyaddition cure. Cure requires elevated temperature: typically 175°C for 2 hours post-gel, followed by 220°C for 4 hours post-cure to achieve full imidization and Tg >250°C. Unlike epoxy coatings (maximum ~180°C) or silicone resins (~200°C), BMI maintains flexural modulus >3 GPa above 200°C with <10% degradation. Applications include engine bay protective coatings, jet engine nacelle composite skins, and PCB laminates for millimeter-wave radar systems where conventional FR-4 epoxy laminates fail at operational temperatures above 150°C.