Operational characteristics of new biological lubricants

Abstract

The lubricating characteristics of ultrathin interlayers of bio-oil RMO made from coastal algae P.Moriformis are investigated in this work. One of the most important qualities of the oil is its lubricity of the friction surfaces. It determines the possibility of formation of a stable separating film between contact surfaces, with orientational ordering in wall adjacent layers, with the strength value required in the boundary friction regime. The structural characteristics of such epitropic-liquid crystal (ELC) layers are essential when choosing a lubricant. Static friction pair was studied by the optical method of admixtured absorption dichroism. It was found that the value of the order parameter of ELC layer and its equilibrium thickness are much higher in compare with the layers of aliphatic hydrocarbons, which are the basis of modern mineral lubricants. The rheological characteristics of ultrathin interlayers were studied in a dynamic triad of friction. Processing of the effective viscosity coefficient dependence on the shear rate, interlayer thickness and temperature allowed us to estimate the value of equilibrium thickness of the ELC layer, which coincides with the results of optical measurements. The marked structural peculiarities of the ELC in the biooil interlayers are conditioned with the formation of molecular associates of oleic acid, which is the main component of studied oil.