SynopsisCrosslinking of 4,4'(bismaleimido)diphenyl ether (BM) was investigated in presence of bis(maminophenyl) methylphosphine oxide (BAP), tris(m-aminopheny1)phosphine oxide (TAP), diaminodiphenyl ether (E) and 3,3-bis(p-aminophenyl)phthalide (AP). These crosslinked resins were examined for thermal stability by thermogravimetric analysis. A slight decrease in initial decomposition temperature, the temperature of maximum rate of weight loss, was observed, though the char yield in nitrogen atmosphere a t 8OOOC did not change appreciably. Glass-cloth-reinforced laminates were fabricated from BM and amine mixtures. An improvement in mechanical properties was observed in the presence of phosphorus-containing di-and triamines.