Film-forming properties of estolides

Abstract

Estolides are biobased materials obtained from the synthesis of ingredients derived from agricultural products. They are oligoesters obtained by the reaction of fatty acids and/or methyl esters with a double bond. By varying the chemistries of the starting materials and the reaction conditions, estolides of varying chemical structures (e.g., branching), and physical properties (e.g., mol wt, viscosity, pour point, cloud point) are obtained. Estolides have been found to have suitable properties for some lubrication applications. In this work, the effect of estolide physical/chemical variability on film thickness and pressure-viscosity coefficient (pvc) were examined. The results showed that estolides have lower pvc than the non-polar hydrocarbon PAO, but much higher than seed oils (e.g., soybean, jojoba, canola), which are used as feedstock in estolide synthesis. The film thickness and pvc properties of estolides were also found to be dependent on the structure (e.g., homo-versus co-oligomer) and purity of the estolide oils.

Chemistry and physical properties of estolides

“…good oxidative stability (Cermak and Isbell 2003b;Biresaw et al, 2007;Cermak et al, 2008). Table 9 summarizes the oxidative performance of oleic estolide 2-ethylhexyl esters with coco-oleic estolide 2-ethylhexyl esters.…”

Viscosity modification of high‐oleic sunflower and castor oils with acid oils‐derived estolides for lubricant applications

“…In previous works [19,20], different polymeric additives were tested in order to design vegetable oil-based lubricant formulations with increased viscosities. In this sense, as previously reported [21][22][23], estolides can be used as alternative biodegradable lubricants with different ranges of viscosities depending on their chemical structure, polymerization degree, etc. Even a much wider viscosity range can be achieved by blending various ratios of estolides obtained from different origin with vegetable oils of different viscosities, such as high-oleic sunflower (HOSO) and castor oils (CO).…”

Functionalization of soy fatty acid alkyl esters as bioplasticizers

“…The availability of large volumes coupled with new technologies to produce specialized designer products (e.g., high oleic oils), from different routes (through breeding, genetic modifications, fermentation) along with improved yields and lower cost of production, makes the fats and oils an ideal raw material for industrial applications . The suitable industrial applications for fats and oil derivatives include plasticizers , adhesives , crosslinkers , coatings , lubricants , electrical insulation (transformer) fluids , heat transfer fluids , chemicals and polymers , among others. Public awareness and concern about the environment are nudging the industry to look for bio‐based products from renewable materials like vegetable oils and their derivatives to replace petroleum‐derived products for industrial applications.…”