Novel bis cyclic ureas are disclosed having the formula ##STR1## WHEREIN C.sub.n H.sub.2 n represents alkylene from 4 to 12 inclusive and provided there are at least 4 carbon atoms in succession in the chain and R is the residue obtained by the removal of both halogen atoms from a diacid halide. The bis cyclic ureas are easily converted to a novel class of aliphatic diisocyanates simply by heating. Alternatively, they are blended with polymeric polyols to form one-component storage stable compositions which are thermally converted to polyurethane resins without any significant volatile or side product formation.