titleOfInvention |
Azeotropic compositions of perfluorohexane, or 1,1,1,4,4,4-hexafluorobutane, or 1,3-dioxolane and hydrocarbons having 5 or 6 carbon atoms |
abstract |
Azeotropic compositions made up of: a) one compound selected from (1) about 26 to about 88 % by weight perfluorohexane, (2) about 4 to about 50 % by weight 1,3-dioxolane, or (3) about 64 to about 87 % by weight 1,1,1,4,4,4-hexafluorobutane; and b) one compound selected from (1) about 20 to about 74 % by weight 2-methyl butane, (2) about 13 to about 53 % by weight n-pentane, (3) about 75 to about 96 % by weight cyclopentane, (4) about 14 to about 79 % by weight 2-methyl pentane, (5) about 13 to about 77 % by weight 3-methyl pentane, or (6) about 12 to about 69 % by weight n-hexane, in which the sum of weight percent a) plus weight percent b) is approximately 100 percent, have been found to be useful as blowing agents in the production of rigid polyurethane foams. |