Advances in the Standards & Applied Sciences

Advances in the Standards & Applied Sciences

Functional Additives and Polymer-Based Strategies for High-Performance Engine Oils

Document Type : Review Article

Authors
Nooshin Gholipour Zanjani 1
Fatemeh Arabgol 2
1 Chemistry and Petrochemistry, Standard Research Instiute
2 Department of Chemical and Materials and polymer Engineering, Buein Zahra Technical University, Buein Zahra, Qazvin, Iran
10.22034/asas.2026.564069.1090
Abstract
Reducing friction and wear is crucial for maintaining engine efficiency and prolonging its lifespan. Modern engine oils achieve this through a carefully balanced combination of base oils and additives that work together to maintain viscosity, protect surfaces, and enhance overall performance. Recent research highlights the role of nanoparticles, viscosity index improvers, and bio-based thickeners in reducing friction, enhancing thermal stability, and improving load-bearing capacity. Yet, conventional additives can struggle under extreme conditions, such as high shear or high temperature. Viscosity index improvers (VIIs) are essential polymeric additives used to stabilize the temperature–viscosity behavior of lubricants. Their ability to enhance viscosity at elevated temperatures while maintaining fluidity at low temperatures enables broad operational performance across automotive, industrial, and hydraulic systems. Emerging smart polymers, including polymer brushes and supramolecular networks, could be studied to provide adaptive viscosity control and superior stability. This review consolidates current insights on base oils, additive technologies, and advanced polymeric systems, examining their mechanisms, benefits, and potential to shape the next generation of high-performance lubricants. Additionally, the research revealed that the polymer's molecular weight, structure, and polarity can significantly impact its ability to enhance the viscosity index and reduce friction.
Keywords
Viscosity index improver
Polymer additives
Lubricant formulation
Subjects
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Advances in the Standards & Applied Sciences
Volume 3, Issue 3
Spring 2025
Pages 90-99