Physico-chemical and tribological properties of isopropyl-branched chicken fat

•Chicken fat (CF) is a low-value by-product of meat production.•CF was modified by converting the double bonds to isopropyl branches.•Modified CF displayed better oxidative stability compared to CF.•Modified CF displayed increased viscosity and density compared to CF.•Modified CF has a potential to be used as an alternative animal-based bio-lubricant. Unlike vegetable oils, extensive efforts have not been made to chemically modify animal fats so that to improve their physico-chemical properties and be utilized as renewable resources to replace petroleum-based products such as lubricants. In this study, we have explored the possibility of utilizing chicken fat as a lubricant by changing its physical and tribological properties through chemical modification. Chicken fat was chemically modified by introducing isopropyl group into the unsaturated fatty acid components of the triglyceride using the industrially produced Lewis acid, ethylaluminum sesquichloride. The modified chicken fat was characterized using a combination of different analytical techniques including GC–MS, NMR and GPC. The physical and tribological properties of the modified and regular chicken fat as well as their blends with high oleic sunflower oil (HOSuO) were investigated. Compared to regular chicken fat, the modified chicken fat displayed higher density but their solubility in HOSuO and Polyalphaolefin (POA-6) was found to be similar. The modified chicken fat also exhibited better oxidative-stability, higher kinematic viscosity but lower viscosity index compared to the regular chicken fat and HOSuO. Unlike the regular chicken fat, blending of modified chicken fat with HOSuO led to an increase in density and improvement in oxidative stability. The present study demonstrated that animal fats could be chemically modified to improve their physicochemical properties like that of vegetable oils and they can be considered as alternative renewable resources for generating value-added products such as biolubricants for various applications.