Understanding and utilising π-π interactions in hydrocarbons: towards advanced lubricants and fuel additives

Abstract

Aromatic interactions in a non-porous solvents have been significantly overlooked in the past few decades. In contrast aromatic interactions in polar solvents, in particular water have been studied extensively leading to an in depth understanding of these interactions and driving forces in these media. The first chapter of this thesis reviews the nature of aromatic interactions, how to best define and evaluate their strength, as well as presenting a historical perspective on aromatic interactions in non-polar environments.The second chapter of this thesis describes the strength and driving forces of aromatic interactions in such solvents as heptane, methylcyclohexane, dibutyl ether, squalene and chloroform. This was evaluated by studying an archetypal aromatic donor-acceptor complex between that of naphthalenediimide and dialkoxynaphthalene. A combination of 1H NMR, UV-vis spectroscopy and isothermal calorimetry techniques were employed to elucidate their strength and thermodynamic functions.In the third and fourth chapters the knowledge acquired concerning aromatic interactions in non-polar environments was then employed in the design of lubricant additives. In Chapter 3, as potential friction modifiers in which their behaviour on metal surfaces was probed using reflective absorbance infrared spectroscopy, sum frequency generation spectroscopy, as well as initial rig tests. Finally in chapter 4, as potential soot solubilisation agents in which the interaction of various polycyclic aromatics with perylenediimide was monitored by UV-vis spectroscopy.

Date of Award	23 Nov 2016
Original language	English
Awarding Institution	University of Bath
Sponsors	BP Technology Centre
Supervisor	Dan Pantos (Supervisor), Sofia Pascu (Supervisor), Kevin R. West (Supervisor) & Sorin V. Filip (Supervisor)