摘要 |
The use in conventional polyolefin extrusion foaming processes of a stability control agent (e.g., stearamide, EAA copolymer, etc.) in conjunction with certain mixed blowing agent systems, the mixed blowing agent system containing 60-95 weight percent of 1-chloro-1,1-difluoroethane or 60-95 weight percent of 1,1-difluoroethane. These compounds have a shorter atmospheric lifetime and lower stability than the saturated chlorofluorocarbons presently used as blowing agents or in blowing agent systems. |