Author
Biresaw, Girma | |
SHARMA, BRAJENDRA - University Of Illinois | |
Bantchev, Grigor | |
Kurth, Todd | |
Doll, Kenneth - Ken | |
Erhan, Sevim | |
KUNWAR, BIDHYA - University Of Illinois | |
SCOTT, JOHN - University Of Illinois |
Submitted to: Industrial and Engineering Chemistry Research
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 9/23/2014 Publication Date: 10/7/2014 Citation: Biresaw, G., Sharma, B.K., Bantchev, G.B., Kurth, T.L., Doll, K.M., Erhan, S.Z., Kunwar, B., Scott, J.W. 2014. Elastohydrodynamic properties of biobased heat-bodied oils. Industrial and Engineering Chemistry Research. 53:16183-16195. Interpretive Summary: Widespread use of biobased lubricants is expected to increase the demand for crops such as soybean, whose seeds are important sources of vegetable oils. Successful application of vegetable oils in lubrication requires that they meet stringent requirements critical for the specific applications. For example, soybean and most vegetable oils have viscosity at 40°C of 30-40 cSt. This range of viscosity prevents their use in gear oil and many other lubricant formulations, which require base oils with several-fold higher viscosity. In this work, soybean oil was thermally treated under inert atmosphere to produce heat-bodied oils with viscosity 2- to 50-fold higher than soybean oil. The heat-bodied oils were thoroughly investigated and were found to display acceptable film thickness, viscosity index, and pressure-viscosity coefficient. The use of heat-bodied oils opens up new opportunities for the use of vegetable oils in high viscosity lubricant formulations, thereby increasing the demand for soybean and similar crops. Technical Abstract: Heat-bodied oils were prepared by thermal treatment of soybean oil under inert atmosphere. Different viscosity grades of heat-bodied oils synthesized by varying the reaction time were investigated for various properties including viscosity, viscosity index, elastohydrodynamic film thickness, and pressure-viscosity coefficient. Heat-bodied oils displayed elastohydrodynamic film thickness characteristics typical of lubricating oils. The film thickness of heat-bodied oils increased with increasing entrainment speed and viscosity, decreased with increasing temperature, and was unchanged with varying load. Pressure- viscosity coefficients of heat-bodied oils were estimated from film thickness as well as from physical property data. The pressure-viscosity coefficient values of heat-bodied oils increased with increasing viscosity and decreasing temperature and were in the range displayed by such oils as polyol esters, polyalphaolefins, and petroleum-based base oils. Heat-bodied oils provide access to a wide viscosity range of biobased oils not attainable with vegetable oils, without serious negative impact on critical lubricant properties such as viscosity index, film thickness, and pressure-viscosity coefficient. |