Preparation and Tribological Performance of Two-Component Supramolecular P-cresol-AOT Gel

In recent years, supramolecular gel lubricants, as a new type of lubricant, have attracted a lot of people's attention. Generally speaking, supramolecular gel lubricants include gelators and solvent, among which solvent can be water, oil, organic solvent or ionic liquid. Gels are formed by self-assembly between gelators through non-covalent interaction, and three-dimensional network structure is formed in the solvent. As a lubricant, the gel has good thixotropic and creep recovery properties and can be converted into a liquid during friction tests, thus reducing the problems of machine resistance and heat dissipation. According to the literature, gelators can form gel lubricants in ionic liquid, base oil and water for the field of lubrication. Gels are formed by self-assembly in various solvents by non-covalent interaction between molecules. And gels formed in base oil is a very important lubricant (base oil includes mineral oil, synthetic base oil, synthetic engine oil, synthetic lubricating oil and ionic liquid). Supramolecular gel lubricants not only have good thixotropy and thermal reversibility, but also can significantly improve the lubrication performance. Although supramolecular gel lubricants have many excellent characteristics, they also have some problems, such as the complexity of gelators and high synthesis cost. To settle these problems, a kind of two-component gel lubricant were reported in this paper. The physical and chemical performances of the gel can be adjusted by transposing the gelators composition. Tribological experiments showed that the gels had satisfactory anti-friction and anti-wear effect, moreover, the two-component gels had the advantages of simple preparation and adjustability. Therefore, the two-component gel lubricant had a good application prospect. As other studies have reported, the two-component gelators were bound by non-covalent bonds (such as π-π stacking, hydrogen bonding and electric dipole moment). It has been reported that gelators can gel only a few numbers of base oils. In order to generalize the application of gel lubricants, the gelators should gel as much of the base oil as possible, we intend to prepare a gelator that can make more base oils into gels. In this paper, a kind of two-component supramolecular gel lubricants, i.e. p-Cresol and AOT (p-Cresol-AOT) in a variety of base oils, was reported. (Base oil includeed mineral oil, synthetic base oil, synthetic engine oil, synthetic lubricating oil). Here a kind of two-component supramolecular gel lubricants i.e. p-Cresol and AOT (p-Cresol-AOT) in a variety of base oils was reported. The gelators had a strong self-assembly ability to gel multiple base oils, involving mineral base oils, synthetic base oils and synthetic engine oils. Firstly, the self-assembly mechanism and rheological performances of the gels were explored by means of nuclear magnetic, FTIR and RS6000 rotational rheometer. The results showed that the gelators mainly formed an ordered structure through supramolecular self-assembly by intermolecular non-covalent interaction. The tribological performances of the gels were tested by SRV-IV. The gels can improve the lubricity and load carrying capacity. This excellent lubrication properties were mainly attributed to the fact that the gel formed the protective film at the metal surface, thereby reducing the direct contact and improving the lubrication properties.