A novel pour point depressant was synthesized by developing a polymeric nanocomposite using polymethacrylate and magnetite nanoparticles. The primary objective was to assess and compare the efficacy of PMA and PMA/Fe3O4 nanocomposite in reducing the gelation point, yield stress, apparent viscosity, and pour point of waxy crude oil. Extensive assessments were conducted to evaluate the performance of these additives. Rheometry tests were employed to measure the pour point of the lubricating oil pour point following the addition of PMA and PMA/Fe3O4 nanocomposite. The findings demonstrated a significant reduction in pour point, reaching values of − 18 °C, − 27 °C, − 24 °C, and − 36 °C for CP1, CP2, NP1, and NP2, respectively, at an optimal concentration of 10,000 ppm. Various characterization techniques such as Fourier Transform Infrared Spectrometer, Proton Nuclear Magnetic Resonance, X-ray Diffraction, Scanning Electron Microscope, Differential Scanning Calorimetry, Dynamic Light Scattering, Polarized Optical Microscope, and Gel Permeation Chromatography were utilized to analyze the polymers. Furthermore, the effectiveness of each polymer as a viscosity index improver (VII) and pour point depressant for mineral-based oil was evaluated. The mechanism of action of the polymers as pour point depressants was investigated through photomicrographic analysis. Additionally, the rheological properties of the formulated lubricant were assessed and reported. Thermogravimetric analysis was used to determine the thermal stability of the polymers, revealing that the copolymer nanocomposites exhibited higher thermal stability, viscosity index (VI), and molecular weights compared to the copolymers alone. These enhancements in thermal stability and molecular properties contributed to the improved pour point depressant (PPD) properties. Overall, the study successfully synthesized a novel pour point depressant and evaluated its performance using various tests and characterization techniques. The results demonstrated the effectiveness of the additives in reducing the pour point and improving the thermal stability of the lubricating oil.
