Abstract: Particulate expandable styrene polymers are coated with a distilled acetylated monoglyceride product to reduce the cooling time of articles molded from such expandable styrene polymers. Coating of the expandable particulate styrene polymer is obtained by contacting the polymer with an emulsion of a distilled acetylated monoglyceride and water with a suitable surfactant. The distilled acetylated monoglyceride is a liquid at room temperature and is substantially completely acetylated.

Abstract: A method of impregnating polystyrene beads with an aliphatic hydrocarbon, rendering it into expandable polystyrene. The method involves the use of an improved impregnating solution or bath. The solution includes water, an expanding agent, the polystyrene beads and soaps which act as anti-agglomeration agents. The beads are maintained in the solution for a selected time period and at a temperature and pressure suitable to permit the expanding agent to impregnate the beads. The beads are then separated from the solution and, after drying, they are ready for use, no further processing being required.