Abstract: There are disclosed refrigeration working fluid compositions comprising tetrafluoroethane refrigerants and certain polyol esters of C7-C10 branched alkanoic acids or mixtures of such branched acids with linear C7-C10 monoalkanoic acids. The polyols are mono-, di- or technical grade pentaerythritol or trimethylolpropane; the esters exhibit suitable viscosity ranges and miscibility with refrigerants over a broad compositional range. The acids have a defined average effective carbon chain length and a certain degree of methyl branching for polyols other than trimethylolpropane.

Abstract: A lubricant which is prepared from at least one synthetic ester composition exhibiting thermal and oxidative stability which comprises the reaction product of 3,5,5-trimethyl-1-hexanol and an acid or anhydride; and a lubricant additive package; whereby the incorporation of an antioxidant in the lubricant additive package for the purpose of maintaining oxidative and thermal stability of the crankcase lubricating oil formulation to at least 20 minutes as measured by HPDSC at 220.degree. C., 3.445 MPa air and 0.5 wt. % dioctyl diphenyl amine can be either reduced or eliminated. The synthetic ester composition preferably exhibits the following additional properties: a metals content of 10 ppm or less metals based on the total synthetic ester composition, an ash content of 15 ppm or less ash based on the total synthetic ester composition, a total acid number of 0.05 mg KOH/g or less, and a volume resistivity of at least about 1.times.10.sup.11 ohm cm.

Abstract: A synthetic ester composition which exhibits thermal and oxidative stability, lower friction coefficient and lower wear, wherein the ester composition comprises the reaction product of: a branched or linear alcohol having the general formula R(OH).sub.n, wherein R is an aliphatic or cyclo-aliphatic group having from about 2 to 20 carbon atoms and n is at least 2; and at least one branched mono-carboxylic acid which has a carbon number in the range between about C.sub.5 to C.sub.13 ; wherein the synthetic ester composition has between about 5-35% unconverted hydroxyl groups, based on the total amount of hydroxyl groups in the branched or linear alcohol.