Defense Date


Document Type


Degree Name

Master of Science



First Advisor

Dr. B. Frank Gupton

Second Advisor

Dr. M. Samy El-Shall

Third Advisor

Dr. Hani El-Kaderi

Fourth Advisor

Dr. Everett Carpenter

Fifth Advisor

Dr. Nastassja Lewinski


For decades, global regulations and government mandates have driven technological developments to improve vehicle fuel economy. Tribological components found in all automotive engines contain metal-on-metal contact zones that may result in increased friction and wear, reducing overall engine efficiency. Lubricant additives such as antiwear and friction modifying components are added to motor oils to prevent some of the damages that may occur at contact zones and improve friction. The effects of other additive components, such as dispersants, that are prevalent in a lubricant additive package on the anti-wear layer remain relatively unknown. Polyisobutenyl Succinimide (PIBSI) dispersants were evaluated for their interactions with the ZDDP antiwear component. The physical and chemical properties and friction of the tribofilms formed in presence of dispersants were defined revealing a previously unknown structure-activity relationship. Further analysis of ZDDP and dispersants revealed surface and bulk fluid interactions.


© The Author

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission