Abstract: Polymer blends are described that are formed from a transient polymer material, a polymer comprising an acrylonitrile group (e.g., ABS, SAN), and/or one or more polyester polymers. For blends in which two or more polyester polymers are blended with a transient polymer material, at least two of the polyester polymers are immiscible with one another, and one of the polyester polymers has a glass transition temperature less than or equal to 0° C. The polymer blends herein can decompose into liquid phase decomposition products upon exposure to a transience reaction trigger in less than 8 hours even at temperatures of less than ?20° C.