SYNTHETIC LIQUID SPACE LUBRICANTS

THE OBJECTIVE OF THE PROPOSED INVESTIGATION IS THE PRODUCTION AND CHARACTERIZATION OF LIQUID SPACE LUBRICANTS OF HIGH VISCOSITY INDEX, A KINEMATIC VISCOSITY OF 90-150 CS AT 40 DEG C, GOOD COMPATIBILITY WITH BEARING MATERIALS, AND A VAPOR PRESSURE OF >225 DEG C UNDER A PRESSURE OF 1 MM HG. A FURTHER OBJECTIVE IS TO INVESTIGATE THE THERMAL STABILITY AND THE ANTIWEAR CHARACTERISTICS OF ALL COMPOUNDS PRODUCED, E.G., DETERMINING THE VISCOSITY AND VAPOR PRESSURE OF THE MATERIALS AFTER EXPOSURE TO ELEVATE TEMPERATURE. THE THREE COMPOUND CLASSES PROPOSED FOR INVESTIGATION ARE SILAHYDROCARBONS, HYDROGENATED POLYALPHAOLEFINS, AND, TO A LESSER EXTENT, ALKYLBENZENES. ALL OF THESE COMPOSITIONS ARE KNOWN TO POSSESS GOOD LUBRICANT PROPERTIES, RELATIVELY HIGH VISCOSITY INDICES, AND ACCEPTABLE THERMAL STABILITY; YET NONE HAS BEEN PRODUCED THUS FAR THAT WILL MEET THE SPECIFIED LOW VOLATILITY/VAPOR PRESSURE CHARACTERISTICS. THE PROPOSED APPROACH WILL THEREFORE BE TO REPRODUCE STRUCTURAL ARRANGEMENTS SIMILAR TO THOSE ALREADY KNOWN, BUT OF MOLECULAR WEIGHTS HIGH ENOUGH TO DECREASE THE VAPOR PRESSURE TO OR BELOW THE DESIRED RANGE WITH SUFFICIENT STRUCTURAL AND COMPOSITIONAL VARIETY TO ENSURE THE NEEDED LIQUID CHARACTER.