Synthesis and Characterization of Iso-Undecenoic and Iso-Undecanoic Acids Based Polyol Esters

Abstract

The polymerization of 10-undecenoic acid (UDA) was carried out in the presence of montmorillonite K10 clay catalyst (5% of UDA) and deionized water (2.5% of UDA) at a temperature of 250 °C in an autoclave. The UDA polymerized product is a mixture of monomer acids (47−51%), dimer acids (30−32%), and higher polymeric acids (17−23%). The present study describes the isolation of less valuable monomer acids fraction (iso-undecenoic acid) through distillation from polymerization reaction product. This monomer acids fraction was found to be a mixture of iso-undecenoic acid (93−96%) and γ-undecalactone (4−7%) when analyzed by GC-MS. Monomer acids fraction was hydrogenated to also give hydrogenated monomer acids (iso undecanoic acids). Finally, the esterification of monomer and hydrogenated monomer acids fractions were done by the reaction with different polyols like neopentyl glycol (NPG), trimethylol propane (TMP), trimethylolhexane (TMH), and pentaerythritol (PE). Physicochemical and lubricant properties of all the synthesized polyol esters were evaluated including density, kinematic viscosity, pour point, flash point, thermal stability (TGA), oxidation stability (DSC), copper corrosion, weld load, and wear. All the synthesized polyol esters were found to be suitable as hydraulic fluids and automotive lubricants base stocks. Comparatively the iso-undecenoic acid based polyol esters were showed excellent pour point, viscosity-temperature properties, and good thermal stabilities, while the iso-undecanoic acid polyol esters showed good oxidation stability.

Green lubricants production from Nile tilapia waste and prediction of physical properties through molecular dynamics simulations

“…In addition to the composition of fatty acids, another factor that influences the melting point of polyesters is the chain structure of the polyol used in the synthesis. The same behavior verified for Tilapia triester and tetraester, was also observed by other researchers, where regardless of the fatty acid composition, in all works, esters with pentaerythritol always presented higher melting point or pour point values than the TMP esters (Moreira et al, 2020;Padmaja et al, 2012;Yasa et al, 2017). As an example, in work with Moringa esters, pentaerythritol esters (m.p.…”

“…Among the synthesized esters, we highlight the pentaerythritol derivative ( T onset 323.1°C) that presented a better performance with an initial temperature higher than the trimethylolpropane ester ( T onset 311.8°C). Padmaja et al (2012) and Yasa et al (2017) found similar results with the pentaerythritol derivative more thermally stable than trimethylolpropane esters but using different raw material for the production of the biolubricant. The onset, burnout, and DTG peak temperatures for TO, T‐TMPE, and T‐PEE were compiled in Table S4.…”

Excellent Properties of Dimer Fatty Acid Esters as Biolubricant Produced by Catalyst‐ and Solvent‐Free Esterification

“…Yang et al. (2013) reported dimerization of oleic acid in the presence of Montmorillonite (9 wt%) at reaction temperature of 260 °C for 8 hours (h) affording 72% yield . Using similar catalyst, Yasa et al.…”

Enzymatic Synthesis of a Polyol Ester from Levulinic Acid and Trimethylolpropane and Its Tribological Behavior as Potential Biolubricant Basestock

“…The flashpoint of TMP-tri-LA ester was determined to be 223 °C above, which reached the standard of low evaporation requirement of lubricants. Generally, polyol esters with a flash point ≥165 °C can lie well within the range of hydraulic oils [ 13 ].…”