Soybean Oil as a Biocompatible Multifunctional Additive for Lubricating Oil

Abstract

The application of greener additives based on vegetable oils in the formulation of biolubricants has attracted considerable interest due to their biocompatibility and enhanced multifunctional performances compared to conventional additives. In this investigation, homopolymers of soybean oil and copolymers with methyl acrylate, 1-decene and styrene were synthesized by a thermal method using azobisisobutyronitrile as a radical initiator. Characterization of the prepared polymers was performed by spectral (NMR, IR), viscometric analysis and gel permeation chromatography. Performance evaluations of the polymers as pour point depressant, viscosity modifier/viscosity index improver (VII) and antiwear in different base oils (mineral) were conducted by standard ASTM methods. Biodegradability of the prepared additives was tested against fungal pathogens and micro-organisms by the disc diffusion method and soil burial test method, respectively. Thermal stability of each of them was evaluated and included. The multifunctional performances were compared and reported.