| abstract |
Forming composition containing an azeotropic or azeotrope-like mixture containing cis-1,1,1,4,4,4-hexafluoro-2-butene. The foam-forming composition comprises (a) cis-1,1,1,4,4,4-hexafluoro-2-butene and a mixture of methyl formate, 1,1,1,3,3-pentafluorobutane, trans An azeotropic or azeotrope-like mixture of 1,2-dichloroethylene, pentane, isopentane, cyclopentane, HFC-245fa or dimethoxymethane; And (b) an active hydrogen-containing compound having at least two active hydrogens. Also disclosed are closed-cell polyurethane or polyisocyanurate polymer foams made from the reaction of an appropriate amount of a foam-forming composition with a suitable polyisocyanate. Also disclosed is a process for preparing a closed-cell polyurethane or polyisocyanurate polymer foam by reacting an effective amount of a foam-forming composition with a suitable polyisocyanate. |