Propiedades físicas y químicas de los estólidos

Estolides are a developing class of natural and synthetic compounds that have been synthesized from hydroxy oils like castor and lesquerella or by the condensation of fatty acids across the olefin of a second fatty acid. Castor and lesquerella estolides are derived from either their triglycerides or their free fatty acids utilizing their hydroxyl moiety to establish the estolide bond. The triglyceride estolides have pour points of 9 to –36ºC but suffer poor oxidative stability with RPVOT times of 29 – 52 minutes even with 1% of an anti-oxidant package incorporated into the samples. In contrast to the triglyceride estolides of castor and lesquerella, the estolides from lesquerolic and ricinoleic acids have very good pour points of –36 to –54ºC. Estolides derived from the acid catalyzed condensation of oleic acid with a variety of fatty acids can be made in good yield and posses a wide range of physical properties. Of particular interest are the saturated capped estolides of oleic that have both good low temperature properties (pour point –5 to – 39ºC) and good oxidative stability. Estolides from meadowfoam fatty acids do not have good low temperature properties but have been extensively used in cosmetics where they provide good moisturizing properties.Los estólidos son una familia de compuestos sintetizados a partir de aceites hidroxilados como los de ricino o lesquerella o mediante la condensación de ácidos grasos sobre el doble enlace de un segundo ácido graso insaturado. Los estólidos de ricino y lesquerela se derivan tanto de sus triglicéridos como de sus ácidos grasos libres empleándose el residuo hidroxilo para formar los ésteres estólidos de los mismos. Los triglicéridos estólidos tienen puntos de fluidez crítica de entre 9 y -36ºC y baja estabilidad, con tiempos de oxidación en recipiente vacío a presión (RPVOT) de entre 29 y 52 minutos incluso con la adición de un 1% de una mezcla antioxidante a las muestras. Estas propiedades contrastan con las de los estólidos de ácido lesquerólico y ricinoleico, que poseen puntos críticos de fluidez mucho más bajos (de -36 a -54). Los estólidos derivados mediante la condensación de ácido oleico con otros ácidos grasos por catálisis ácida pueden realizarse con buen rendimiento y presentan un rango bastante amplio de propiedades físicas. A este respecto son de bastante interés los estólidos de ácido oleico esterificados con ácidos grasos saturados los cuales presentan tanto buen comportamiento a bajas temperaturas (puntos de fluidez crítica de -5º a -39ºC) como buena estabilidad oxidativa. Los estólidos de los ácidos grasos del aceite de prado (Limnanthes alba) no presentan buenas propiedades de lubricación a baja temperatura pero su uso está muy extendido en cosmética, donde muestran buenas propiedades como agente hidratante

J9382

ABSTRACT: δ-Stearolactone was prepared from oleic acid using concentrated sulfuric acid under various conditions in the presence of polar, nonparticipating solvents. δ-Stearolactone was formed in as high as 15:1 ratios over the thermodynamic product, γ-lactone, in the presence of methylene chloride, 100% wt/vol, at room temperature with two equivalents of sulfuric acid for 24 h. This procedure is applicable to other olefinic fatty acids such as estolides and fatty acid methyl esters. Temperature plays a role in the regioselectivity of the cyclization for δ-lactone, as lower temperatures (20°C) gave higher δ/γ ratios. At higher temperatures (50°C) in the presence of sulfuric acid and methylene chloride the yield of lactone was 75% but with a δ/γ ratio of only 0.3:1. Cyclization of oleic acid to lactone also occurred with other acids. Oleic acid underwent reaction with perchloric acid, one equivalent, in the absence of solvent at 50°C, which yielded δ-lactone in a modest yield with a 3.1 δ/γ ratio. The same temperature effect was observed with perchloric acid that was observed in the case of sulfuric acid. Because δ-stearolactone is much more reactive than the corresponding fatty acid, fatty acid ester, or γ-lactone, we believe that it will be a useful synthon for many new industrial products including new biodegradable detergents

US effort in the development of new crops (Lesquerella, Pennycress Coriander and Cuphea)

The US effort for the development of new crops is directed toward the advancement of crops that can be grown in rotation with traditional commodity crops, off-season production and utilization of acreage not currently under cultivation. This effort is intended to have no or minimal impact on crop rotations that are sources for food production. The high oil content and the fatty acid profiles of mustard crops make them suitable for utilization as both fuels and base stocks for functionalized industrial chemicals. Pennycress (thlaspi arvense) and lesquerella (lesquerella fendleri) are representatives of this family and have received much attention due to their potential to grow over winter in rotation with soybean production throughout the Midwest (pennycress) or as a winter annual in the desert southwest (lesquerella). Pennycress is an oilseed crop that produces 36% oil with a wide distribution of fatty acids (principal fatty acid is erucic acid 37%) that make it suitable for production of biodiesel. The key aspect of pennycress is that its lifecycle is complete such that a full season soybean can follow its production in the same growing season. Lesquerella is an oilseed crop containing 30% oil that is composed of 60% hydroxy fatty acids. Hydroxy fatty acids are used in a wide range of industrial and cosmetic applications. Two other New Crops currently under investigation are cuphea and coriander. Cuphea is an oilseed crop that contains 35% oil that is composed of medium chain saturated fatty acids. The current cuphea variety under investigation is high in capric fatty acid (76%) with other cuphea species producing high levels of lauric acid. Cuphea can be grown throughout the Midwest but suffers from several agronomic traits that are currently limiting is potential adaptation. Coriander is also an oilseed crop with 25% oil where the main fatty acid is petroselinic acid (76%). Coriander can be grown under a short season production and has potential to rotate as a second crop following winter wheat. Petroselinic acid can be ozonolytically cleaved into adipic and lauric acids both high volume industrial chemicals

US effort in the development of new crops (Lesquerella, Pennycress Coriander and Cuphea)

The US effort for the development of new crops is directed toward the advancement of crops that can be grown in rotation with traditional commodity crops, off-season production and utilization of acreage not currently under cultivation. This effort is intended to have no or minimal impact on crop rotations that are sources for food production. The high oil content and the fatty acid profiles of mustard crops make them suitable for utilization as both fuels and base stocks for functionalized industrial chemicals. Pennycress (thlaspi arvense) and lesquerella (lesquerella fendleri) are representatives of this family and have received much attention due to their potential to grow over winter in rotation with soybean production throughout the Midwest (pennycress) or as a winter annual in the desert southwest (lesquerella). Pennycress is an oilseed crop that produces 36% oil with a wide distribution of fatty acids (principal fatty acid is erucic acid 37%) that make it suitable for production of biodiesel. The key aspect of pennycress is that its lifecycle is complete such that a full season soybean can follow its production in the same growing season. Lesquerella is an oilseed crop containing 30% oil that is composed of 60% hydroxy fatty acids. Hydroxy fatty acids are used in a wide range of industrial and cosmetic applications. Two other New Crops currently under investigation are cuphea and coriander. Cuphea is an oilseed crop that contains 35% oil that is composed of medium chain saturated fatty acids. The current cuphea variety under investigation is high in capric fatty acid (76%) with other cuphea species producing high levels of lauric acid. Cuphea can be grown throughout the Midwest but suffers from several agronomic traits that are currently limiting is potential adaptation. Coriander is also an oilseed crop with 25% oil where the main fatty acid is petroselinic acid (76%). Coriander can be grown under a short season production and has potential to rotate as a second crop following winter wheat. Petroselinic acid can be ozonolytically cleaved into adipic and lauric acids both high volume industrial chemicals