A method of preparing a mono(C4-32 hydrocarbyl) ester of a mono(C1-4 alkyl)polyoxyalkylene glycol by contacting a C1-4 alcohol and an alkylene oxide comprising ethylene oxide, propylene oxide, or a combination comprising at least one of the foregoing under conditions effective to provide a first mono(C1-4 alkyl)polyoxyalkylene glycol having a first average degree of polymerization; contacting the first mono(C1-4 alkyl)polyoxyalkylene glycol and the alkylene oxide under conditions effective to provide a second mono(C1-4 alkyl)polyoxyalkylene glycol having a second average degree of polymerization that is higher than the first average degree of polymerization; and contacting the second (C1-4 alkyl)polyoxyalkylene glycol and a C4-32 carboxylic acid to provide the mono(CC4-32 hydrocarbyl) ester of a mono(C1-4 alkyl)polyoxyalkylene glycol.