A composition useful in the manufacturing of plastic cookware includes a polyetherimide resin and an acidic additive selected from the group consisting of aliphatic carboxylic acids having a vapor pressure less than one atmosphere at 300° C., aromatic carboxylic acids having a vapor pressure less than one atmosphere at 300° C., and combinations comprising at least one of the foregoing acidic additives. In one embodiment, the composition further comprises an additional resin, such as a polyester resin. The acidic additive is effective in improving the mold release and increasing the melt flow of the composition. Articles including the composition and a method for preparing the composition are also described.