Development and Evaluation of Castor Oil-Based Additives for Sustainable Lubricating Oils

Abstract

The gradual reduction of worldwide crude oil stores, increasing costs of crude oil, and escalating environmental worries are critical matters with the capacity to profoundly affect human existence. Meeting these challenges necessitates researchers' dedicated focus on discovering alternative solutions and advancing the creation of a sustainable ecosystem.This research seeks to tackle these issues by creating homopolymers of castor oil (CO) and copolymers using Castor oil  and n-butyl acrylate, without solvent. The process uses benzoyl peroxide (BZP) as the initiator for polymerization, and the resulting polymers are tested for their effectiveness as additives in lubricating oils. Analyzing the synthesized polymers entails utilizing spectroscopic methods like FT-IR and NMR spectroscopy for characterization purposes. Thermo-gravimetric analysis (TGA) is employed to evaluate thermal stability, while gel permeation chromatography (GPC) is utilized to ascertain molecular weight. The effectiveness of additives in enhancing viscosity index (VI) and reducing pour point (PP) is being examined through the ASTM procedure using the SN150 mineral oil standard. The disk diffusion method was utilized to evaluate the biodegradability of various polymers. The results from the experiment and the analysis of the data suggest that the copolymer shows potential as a versatile lubricating oil additive when compared to the homopolymer. Furthermore, elevating the concentration of n-butyl acrylate within the copolymer leads to heightened average molecular weight, better thermal stability, and superior effectiveness as a viscosity index improver (VII) and pour point depressant (PPD). This implies that modifying the copolymer's makeup can enhance its molecular properties and effectiveness when used as an additive in lubricating oil.