Multifunctional Lube Oil Additives Based on Octadecene-Maleic Anhydride Copolymer

Abstract

In the present work, some polymeric additives based on octadecene-maleic anhydride copolymer were prepared and evaluated as multifunctional lube oil additives (viscosity index improvers, pour point depressants, and detergent/dispersant additives). The octadecene-maleic anhydride copolymer reacted with different alcohols (dodecyl, hexadecyl, octadecyl, and docosanol) to prepare four different types of esters then were aminated with different types of amines (dodecyl, hexadecyl, and octadecyl) to prepare another three copolymeric additives. Structures of the prepared compounds were confirmed by infrared (IR) spectroscopy and determination of molecular weight was made using gel permeation chromatography (GPC). The percentage of esterification and amination were determined by 1HNMR. The efficiencies of the prepared compounds as viscosity index improvers, pour point depressants, and detergents/dispersants were investigated. It was found that the efficiency of the prepared compound as viscosity index improvers increases with increasing the concentration of additives and with increasing the alkyl chain length of prepared compounds, whereas the efficiency of the prepared compounds as pour point depressants increases with decreasing the concentration of the prepared polymers. On the other hand, the prepared compounds showed excellent dispersion power.