Synthesis, characterization, and performance evaluation of N,N-Dimethylacrylamide-alkyl acrylate copolymers as novel multifunctional additives for lube oil

Three copolymeric and two homopolymeric additives were synthesized utilizing the C18 alkyl acrylate (C18Ac) and N,N-dimethylacrylamide (DMAA) monomers. Three additives named as additive 1, additive 2, and additive 3 were synthesized by varying the ratio between C18Ac: DMAA as 1:1, 1:2 and 2:1 respectively by free radical polymerization using AIBN (azobis(isobutyronitrile)) as initiator, whereas additive 4 and additive 5 were the homopolymers of C18Ac and DMAA, respectively. All the synthesized polymers were characterized by FT-IR (fourier transform infrared spectroscopy), NMR (nuclear magnetic resonance), and GPC (gel permeation chromatography) analysis. Performance evaluation of the copolymers as viscosity index improver (VII), pour point depressant (PPD), anti-wear, antifriction, and anticorrosion additives in polyol base oil was done by standard methods. As far as the VII, anti-wear, antifriction, and anticorrosive properties are concerned, additive 2 revealed best performance; however, none of the above synthesized additives was found to be suitable for PPD activity.