LIQUID FUEL COMPOSITIONS

摘要

The present invention provides a method of improving the performance of the lubricant of an internal combustion engine, said method comprising fuelling an internal combustion engine containing the engine lubricant with a liquid fuel composition comprising: - a base fuel suitable for use in an internal combustion engine; and - one or more poly (hydroxycarboxylic acid) derivative having a terminal amine group having formula (III) : [Y-CO[O-A-CO]n-Zp]m-X wherein Y is hydrogen or optionally substituted hydrocarbyl group, A is a divalent optionally substituted hydrocarbyl group, n is from 1 to 100, m is 1 or 2, Z is an optionally substituted divalent bridging group, p is from 0 to 10, and X is terminal amine group or a group carrying a terminal amine group, wherein the terminal amine group is selected from -NR12, wherein R1 is independently selected from hydrogen and a C1-C6 hydrocarbyl group.