Diphenyl ether and benzophenone compositions

Abstract

A functional fluid composition comprises a homogeneous mixture of diphenyl ether and benzophenone and at least one additional component selected from the group consisting of dibenzofuran and naphthalene. In a more specific embodiment, a functional fluid composition comprises a homogeneous mixture of diphenyl ether employed in an amount from about 5 to about 80 weight percent, benzophenone employed in an amount from about 5 to about 50 weight percent, and at least one additional component selected from the group consisting of dibenzofuran and naphthalene employed in an amount from about 5 to about 25 weight percent, the diphenyl ether, the benzophenone, and the at least one additional functional fluid composition is thermally stable up to at least about 650° F. and has a freezing point of less than about 54° F.

What is claimed is: 
     
       1. A functional fluid composition, comprising a homogeneous mixture of from about 5 to about 80 weight percent diphenyl ether and from about 5 to about 50 weight percent benzophenone and from about 5 to about 25 weight percent of at least one additional component selected from the group consisting of dibenzofuran and naphthalene. 
     
     
       2. The functional fluid composition of claim 1, wherein the diphenyl ether, the benzophenone, and the at least one additional component are in proportions such that the functional fluid composition is thermally stable up to at least about 650° F. 
     
     
       3. The functional fluid composition of claim 1, wherein the diphenyl ether, the benzophenone, and the at least one additional component are in proportions such that the functional fluid composition has a freezing point of less than about 54° F. 
     
     
       4. The functional fluid composition of claim 1, further comprising biphenyl employed in an amount from greater than 0 to about 30 weight percent. 
     
     
       5. The functional fluid composition of claim 1, wherein the diphenyl ether is employed in an amount from about 40 to about 60 weight percent, the benzophenone is employed in an amount from about 20 to about 35 weight percent, and the at least one additional component is employed in an amount from about 5 to about 15 weight percent. 
     
     
       6. The functional fluid composition of claim 5, wherein the at least one additional component includes a combination of both dibenzofuran and naphthalene individually employed in amounts from about 5 to about 15 weight percent. 
     
     
       7. The functional fluid composition of claim 6, further comprising biphenyl employed in an amount from about 10 to about 20 weight percent. 
     
     
       8. A functional fluid composition, comprising a homogeneous mixture of diphenyl ether employed in an amount from about 5 to about 80 weight percent, benzophenone employed in an amount from about 5 to about 50 weight percent, and the at least one additional component selected from the group consisting of dibenzofuran and naphthalene employed in an amount from about 5 to about 25 weight percent, the diphenyl ether, the benzophenone, and the at least one additional component being present in such quantities that the functional fluid composition is thermally stable up to at least about 650° F. and has a freezing point of less than about 54° F. 
     
     
       9. The functional fluid composition of claim 8, further comprising biphenyl employed in an amount from greater than 0 to about 30 weight percent. 
     
     
       10. The functional fluid composition of claim 8, wherein the at least one additional component includes a combination of dibenzofuran and naphthalene individually employed in amounts from about 5 to about 15 weight percent. 
     
     
       11. The functional fluid composition of claim 10, further comprising biphenyl employed in an amount from about 10 to about 20 weight percent. 
     
     
       12. The functional fluid composition of claim 1, wherein the homogeneous mixture contains: (a) diphenyl ether employed in an amount from about 50 to about 60 weight percent;   (b) benzophenone employed in an amount from about 28 to about 38 weight percent; and   (c) naphthalene employed in an amount from about 7 to about 17 weight percent.   
     
     
       13. The functional fluid composition of claim 1, wherein the homogeneous mixture contains: (a) diphenyl ether employed in an amount from about 49 to about 59 weight percent;   (b) benzophenone employed in an amount from about 27 to about 37 weight percent; and   (c) dibenzofuran employed in an amount from about 9 to about 19 weight percent.   
     
     
       14. The functional fluid composition, of claim 1, wherein the homogeneous mixture contains: (a) diphenyl ether employed in an amount from about 42 to about 52 weight percent;   (b) benzophenone employed in an amount from about 23 to about 33 weight percent;   (c) naphthalene employed in an amount from about 5 to about 15 weight percent; and   (d) biphenyl employed in an amount from about 11 to about 21 weight percent.   
     
     
       15. The functional fluid composition, of claim 1, wherein the homogeneous mixture contains: (a) diphenyl ether employed in an amount from about 41 to about 51 weight percent;   (b) benzophenone employed in an amount from about 22 to about 32 weight percent;   (c) dibenzofuran employed in an amount from about 6 to about 16 weight percent; and   (d) biphenyl employed in an amount from about 11 to about 21 weight percent.   
     
     
       16. The functional fluid composition, of claim 1, wherein the homogeneous mixture contains: (a) diphenyl ether employed in an amount from about 44 to about 55 weight percent;   (b) benzophenone employed in an amount from about 24 to about 34 weight percent;   (c) dibenzofuran employed in an amount from about 7 to about 17 weight percent; and   (d) naphthalene employed in an amount from about 5 to about 15 weight percent.   
     
     
       17. The functional fluid composition, of claim 1, wherein the homogeneous mixture contains: (a) diphenyl ether employed in an amount from about 37 to about 47 weight percent;   (b) benzophenone employed in an amount from about 20 to about 30 weight percent;   (c) dibenzofuran employed in an amount from about 5 to about 15 weight percent;   (d) naphthalene employed in an amount from about 4 to about 14 weight percent; and   (e) biphenyl employed in an amount from about 9 to about 19 weight percent.