Carbon dioxide blown polyurethane packaging foam with chemical nucleating agents

摘要

A method of preparing polyurethane packaging foam for dispensing into a container in which an article is present to be packaged for shipping, wherein the temperature of the polyurethane foam being dispensed into the container is reduced, as is the maximum reaction exotherm temperature. The method involves reacting polymeric isocyanate and polyoxyalkylated polyol precursors in the presence of water as the blowing agent for the foam. A nucleating agent is present in at least one of the precursors and is present in an amount sufficient to reduce the dispensing temperature of the foam reaction product but also the exotherm as the reaction continues to completion. Incorporation of a nucleating agent into the isocyanate and polyol resin components results in a carbon dioxide blown polyurethane packaging foam preferably having a density of 0.2 lb./ft.3 to 2.0 lb./ft.3.