STABILIZATION OF SILICONE LUBRICATING FLUIDS AT 300 TO 400C BY SOLUBLE CERIUM COMPLEXES.
Abstract
The Si-H bond was shown to be involved in the formation of a stable cerium-silicone inhibitor system and this discovery was applied to the development of improved methods for stabilizing silicones. The inhibitory process uses initial reactions between hydrous cerous acetylacetonate and a polymethylhydrogen silicone. These reactions proceed and terminate in aerated refluxing benzene to provide a silicone-soluble adduct. The chemistry of the hydride group was followed quantitatively and some features of structure are postulated for the adduct. The simplified inhibitory process is a two-step reaction. Stabilization is completed by aerating a mixture of the cerium adduct and a silicone oil for one hour at 270 to 280C. There is an optimum concentration of cerium adduct for the stabilization of lightly phenylated dimethyl silicones. The same concentration achieves 100 to 500 percent improvements in the 300C stability of dimethyl silicones and their chlorophenyl- and phenyl-substituted types; with more highly phenyl-substituted silicones, stabilization temperatures are raised to 400C and relative improvement factors roughly parallel those observed at 300C. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 08, 1965
- Accession Number
- AD0612064
Entities
People
- H. R. Baker
- J. G. O'rear
- P. J. Sniegoski
- R. E. Kagarise
Organizations
- United States Naval Research Laboratory