Phosphazene based functional fluid compositions

A functional fluid composition comprising a plurality of different cyclic phosphazene compounds of the general formula:

• (P=N).sub.n (R).sub.a (R').sub.b (R").sub.c (R"').sub.d
• wherein;
• R is at least one alkoxy moiety described by the general formula --OCH.sub.2 (CF.sub.2).sub.y X, with X being hydrogen or fluorine and y being equal to 1 to about 10;
• R', R" and R"' are different aryloxy moieties, each of R', R" and R"' being selected from the group consisting of phenoxy, alkoxy phenoxys, alkylphenoxys, chlorinated phenoxys, fluorinated phenoxys, arylphenoxys, phenoxy phenoxys, fluoroalkyl phenoxys, fluoroalkoxy phenoxys, chlorinated phenoxy phenoxys, fluorinated phenoxys phenoxys and mixtures thereof;
• n is equal to 3 to about 4;
• for each of said phosphazene compounds, each of a, b, c, and d is equal to or greater than zero such that the sum a+b+c+d is equal to 2n;
• and
• for the composition as a whole, the average value of each of a, b, c, and d is greater than 0;
• and
• wherein each of said different phosphazene compounds is present in an amount less than 70% by weight of the total phosphazene content of said composition.