When turbine inlet temperatures hit 1,600°C, only advanced carbon fiber prepreg with Tg > 200°C can survive. The new breed of phenylethynyl-terminated (PETI) epoxy prepregs is redefining aerospace thermal limits. The Tg Paradox Standard aerospace epoxy carbon fiber prepreg (Tg=180°C) loses 80% stiffness at 200°C. Cytec’s CYCOM® 977-