Effect of thermo-mechanical processing on the rheology of oleogels potentially applicable as biodegradable lubricating greases

摘要: This work is focused on the development of oleogels potentially suitable as biodegradable lubricating greases by studying effect that some thermo-mechanical processing variables exert their rheological properties and microstructure. Oleogels were prepared dispersing sorbitan monostearate (SMS) in castor oil under different agitation conditions thermal protocols. The was evaluated performing small-amplitude oscillatory shear (SAOS) measurements, AFM observations mechanical tribological tests usually employed to check lubrication performance stability greases. Rheological can be monitored situ during using a rheo-reactor. Processing such maximum temperature applied disperse gelling agent, heating time, speed cooling rate significantly influence gel strength. Cooling profile most important variable affecting response oleogels. Differences more than one decade values SAOS functions found for processed applying profiles. A moderate SMS dispersion yields oleogel linear viscoelasticity functions. reached this stage should only slightly higher melting point. In general, samples exhibited poor after sample working rolling element, but, contrary, they recovered completely initial consistency resting also exhibiting remarkable lubricant properties. Moreover, tested ball-disc tribometer show friction coefficient inferior those obtained with model lithium