As part of an ongoing effort to develop processable, high-performance
resins for aerospace applications, a phenylethynyl-terminated imide (P
ETI) oligomer designated LaRC(TM) PETI-1 was developed. This reactive
oligomer has a number-average molecular weight of 6300 g/mol and a T-g
of 218 degrees C. Upon curing the reactive oligomer at 350 degrees C
for 1 h, a tough material with a T-g of 249 degrees C was obtained. Th
e properties of cured PETI-1 in the form of composites, adhesive speci
mens, thin films, and neat resin moldings are excellent. The synthesis
, characterization, and mechanical properties of this polyimide are di
scussed. (C) 1996 John Wiley & Sons, Inc.