Two maleimido end-capped poly(ethylene glycol) (m-PEG) of different molecular weights were synthesized and blended at various proportions with bismaleimide resin (4,4'-bismaleimido diphenylmethane) (BDM). The curing behavior and the thermal properties of the m-PEG/BDM blends were studied and presented here. It was found that the addition of m-PEG enhanced the processability of the BDM resin significantly. The processing window of the BDM resin was increased from approximately 20 to 80degreesC. The addition of m-PEG modified resins, however, resulted not only in the reduction in the thermal stability of the blended BDM resin but also elevation of the coefficients of thermal expansion. The changes in thermal/mechanical properties of the blends were found to be proportional to the amounts of m-PEG incorporated. It was observed that the curing behavior, and thermal and mechanical properties, of the blends were independent of the molecular weight of the PEG segment.