Chemical blowing agent compositions and methods

Abstract From the Canadian patent

Abstract of the Disclosure, A method of making a foam injection molded article is disclosed wherein corrosion of the mold element is significantly reduced or substantially eliminated. The method comprises dispersing effective amounts of a primary chemical blowing agent of sodium borohydride and an activation system of sodium bicarbonate/citric acid mix into a polymer resin to form a mixture. The mixture is then heated whereby the activation system releases water and the sodium borohydride reacts with the water to produce hydrogen gas. The mixture is subsequently injected into a mold to obtain expansion of the polymer resin to form the foam article. The invention also comprehends a …