Multifunctional lube oil additives based on maleic anhydride

Copolymer of maleic anhydride with 1-decene was synthesized by using azobisisobutyronitrile as an initiator in toluene solvent and the prepared copolymer was reacted separately with different long chain amines (n-octyl amine, n-decyl amine, and n-dodecyl amine) to get three copolymers. The performance of the polymers in different base oils was evaluated as viscosity modifier (VM) also called viscosity index improver, pour point depressant (PPD), and dispersant by standard ASTM methods. The molecular weight of the polymers was determined by gel permeation chromatography. The TGA value was determined by the standard ASTM method. It was found that the efficiency of the polymers as a VM and dispersant increases with increasing the molecular weight of the polymers as well as with increasing the alkyl chain length. However, the efficiency as a PPD increases with decreasing molecular weight of the prepared polymers and with the decreasing the alkyl chain length.