FOAMING OF POLYISOCYANATE/ACTIVE HYDROGEN-CONTAINING COMPOUND REACTION PRODUCT

1 . Process comprising forming a foamed reaction product obtained by reacting polyisocyanate with active hydrogen-containing compound in the presence of blowing agent comprising 55 to 75 wt % Z-1,1,1,4,4,4-hexafluoro-2-butene and 25 to 45 wt % E-1,1,1,4,4,4-hexafluoro-2-butene, the combined weight of these isomers totaling 100 wt %, to obtain said foamed reaction product.

2 . Process of claim 1 wherein said foaming is carried out at a temperature of at least 100° F. (37.7° C.).

3 . The process of claim 2 wherein the thermal conductivity of said foamed reaction product is not appreciably changed when said foaming temperature is changed within the range of 100° F. (37.7° C.) to 150° F. (65.6° C.).

4 . The process of claim 1 wherein said active-hydrogen-containing compound is polyol.

5 . Composition comprising 55 to 75 wt % Z-1,1,1,4,4,4-hexafluoro-2-butene and 45 to 25 wt % E-1,1,1,4,4,4-hexafluoro-2-butene, the combined amounts of these isomers totaling 100 wt %.

6 . The composition of claim 5 comprising catalyst for the reaction between polyisocyanate and active hydrogen-containing compound,

7 . The composition of claim 6 comprising said active hydrogen-containing compound.

8 . The composition of claim 5 wherein the amounts of said Z-1,1,1,4,4,4-hexafluoro-2-butene and E-1,1,1,4,4,4-hexafluoro-2-butene are 57 to 73 wt % and 43 to 27 wt %, respectively to total 100 wt % of the combined amount of these isomers.

9 . The composition of claim 5 wherein the amounts of said Z-1,1,1,4,4,4-hexafluoro-2- butene and E-1,1,1,4,4,4-hexafluoro-2-butene are 67 to 73 wt % and 33 to 27 wt %, respectively to total 100 wt % of the combined amount of these isomers.

10 . The composition of claim 6 wherein said active hydrogen-containing compound is polyol.