abstract |
Azeotrope-like compositions comprising trichlorofluoromethane, a dichlorotrifluoroethane selected from the group consisting of 1,1-dichloro-2,2,2-trifluoroethane and 1,2-dichloro-1,1,2-trifluoroethane and isopentane are novel compositions particularly useful as blowing agents in the preparation of polyurethane and polyisocyanurate foams. |