| abstract |
This invention provides an insulating extruded thermoplastic polymer closed-cell foam having a thermal conductivity according to EN-13164 of about 35 mW/m.°K or less. The polymer is a monovinyl aromatic polymer with a broad molecular weight distribution. The foam contains blowing agent residuals from production of freshly formed cells of the foam using a blowing agent mixture that includes a primary blowing agent (one or more fluorine-containing carbon compounds and, optionally, carbon dioxide) and a secondary blowing agent (C1-4 alcohol, a C1-5 linear or cyclic hydrocarbon, an alkyl halide, water or a mixture thereof). |