Abstract: The distribution of nitrogen species in a long chain alkenyl succinimide dispersants is quantitated and speciated by means of 15N nuclear magnetic resonance spectroscopy.

Abstract: The nitrogen species in a long chain alkenyl succinimide are quantitated and speciated by means of X-Ray Photoelectron Spectroscopy with speciation being made by chemometrically curve resolving the XPS spectrum.

Abstract: Provided is a lubricant blend including one or more lubricant base stocks and one or more dispersants. The dispersant is chosen from a polyalphaolefin succinimide, a polyalphaolefin succinamide, a polyalphaolefin acid ester, a polyalphaolefin oxazoline, a polyalphaolefin imidazoline, a polyalphaolefin succinamide imidazoline, and combinations thereof. The one or more dispersants are present at 2 to 20 wt % based on the total weight of the blend. The one or more dispersants and the one or more lubricant base stocks are together present at 8 wt % or more of the total weight of the blend. Provided is also a process for making the lubricant blend and a method for the service life of a lubricant.

Abstract: An apparatus for evaluating deposit formation characteristics of lubricant samples. The apparatus includes a reactor chamber having a closed first end and a second end, said closed first end of said reactor chamber forming a lubricant sump and said second end open to the atmosphere, an electric heater for heating a test coupon positioned thereon, said electric heater positioned within said reactor chamber, above said lubricant sump, an air supply tube, said air supply tube having a first end in fluid communication with a source of air and a second end, said second end positioned adjacent the test coupon, said air supply tube having a sample orifice located between said first end and said second end of said air supply tube and a lubricant supply tube, said lubricant supply tube having a first end positioned within said lubricant sump and in fluid communication with a source of lubricant and a second end, said second end positioned within said sample orifice of said air supply tube.