Effect of the Effective Dynamic Viscosity of Plastic Lubricants Produced from Secondary Raw Materials on Their Tribological Properties

The article presents the results of study of the effect of dynamic viscosity on tribological properties of plastic lubricants produced from spent polymers of different origin. For instance, waste motor oil was used as a base oil and grinded solid polymers LDPE (low-density polyethylene), HDPE (high-density polyethylene) та РР (polypropylene) were used as a dispersed phase. It was established that dynamic viscosity of the base oil depends on the origin of this oil and type of polymer thickener. At the same time effective dynamic viscosity makes a significant effect on the lubricating properties of plastic grease. HDPE-based plastic lubricants are considered the most effective lubricants while PP-based ones are considered the least effective. The results of the current research confirmed that, plastic lubricants produced from secondary raw materials can be used as anti-friction lubricants due to their lubricating properties. Moreover, these lubricants are considered a good alternative for existing lubricants as: Mobil Grease Special; NESTE MP Grease; Shell RETINAX Grease CMX1,2; Mobilux EP.