A room temperature curable water-based mold release agent that is useful for demolding composite parts, such as epoxy and polyester based polymer materials. The mold release agent is curable at low temperatures, such as room temperature, but is thermally stable up to conventional epoxy based composite molding temperatures, e.g., greater than 200 or 280 DEG C. The mold release agent is useful for demolding large composite parts that are cured in large ovens at high temperature when the molds themselves are prepped at room temperature before placing in the oven. The mold release agent is also useful for demolding polyester composite parts that are prepared and cured at low temperature such as room temperature.