Submitted to: Annual Meeting and Expo of the American Oil Chemists' Society
Publication Type: Abstract only
Publication Acceptance Date: 2/29/2000
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: Melting point, pour point (PP), and viscosity at both 40 C and 100 C were determined for a series of esters (methyl, butyl, decyl, oleyl, 2-propyl, 2-ethylhexyl, C18-Guerbet, and C24-Guerbet) of meadowfoam, crambe, and oleic fatty acids and estolides. Of the derivatives studied, oleic estolide esters had the lowest melting points, with 2-ethylhexyl and C18-Guerbet esters at -34 C and -43 C, respectively. Both estolides and free fatty acids showed similar melting point curves within the series of esters. Pour points were measured for the same series of free fatty acids and 2-ethylhexyl estolide esters. The pour points of oleic estolides were 5-10 C higher than the corresponding derivative's melting point. The effect of increasing oligomerization on the pour point was also studied, with increasing oligomerization (higher estolide number (EN) yielding higher pour points (EN of 2.96 had a PP of 0 C; EN of 1.1 had a PP of -27 C). Similarly, viscosity increased with higher oligomerization, and free acid estolides generally were several hundred centistokes more viscous than the corresponding esters. Viscosity index ranged from 151 to 225 with the fatty acid esters giving slightly better indices. Hydrogenation of the estolides resulted in a dramatic increase in pour point but only slightly changed viscosity.