Alexander Bilyk

A novel technique for the preparation of secondary fatty amides

A low-temperature synthesis of fatty alkanolamides, fatty diamides and fatty aralkylamides directly from triglycerides and primary amines provides essentially quantitative yields of the various products. The reactions run to completion in 3–12 h at temperatures of 50–60°C, approximately 100°C lower than employed in present conventional practice. The amines are used in excess and serve as solvent, reagent and, perhaps, as catalyst. The amides were characterized by melting point and spectroscopic (infrared and nuclear magnetic resonance) methods. If the mixed amides produced from the various natural triglyceride mixtures of fats and oils are acceptable products, this synthetic method provides these products in satisfactory quality while conserving energy and avoiding the intermediate production of free fatty acids or their esters.

Lipase-catalyzed triglyceride hydrolysis in organic solvent

An investigation of lipases fromRhizomucor miehei,Candida rug osa and porcine pancreas revealed that these enzymes hydrolyzed triglycerides in an organic solvent system. The presence of secondary amines,i.e., diethylamine,N-methylbutylamine, or the tertiary amine, Methylamine, greatly increased the extent of hydrolysis. The lipolysis of tallow took place under mild conditions,e.g., room temperature, moderate shaking and within 20 hr. At 45°C, complete hydrolysis of tallow was obtained in 6 hr. Vegetable oils and a fish oil (cod liver oil) were also hydrolyzed at 20°C byR. miehei lipase in the presence of iV-methylbutylamine for 20 hr. The lipases were recovered for reuse with some loss of activity. Optimum yields of free fatty acids were obtained by usingR. miehei lipase as catalyst.

Separation of cholesterol, and fatty acylglycerols, acids and amides by thin-layer chromatography

A rapid unidimensional thin-layer chromatographic (TLC) method for the separation of neutral lipids is described, using two sequential solvent systems of different polarity. Excellent separations of mono-, di- and triglycerides, fatty acids, fatty amides, and cholesterol are thereby achieved. Separation is accomplished at room temperature and requires 25 min.

Lipase catalyzed formation of fatty amides

Certain lipase preparations were found to facilitate the preparation of fatty amides at 20°C in hexane. Lipase preparations investigated were from the fungiCandida rugosa, Rhizomucor miehei and porcine pancreas. Reactants were various primary alkylamines and fatty acid methyl esters or triglycerides. Moderate yields of fatty amides were obtained using aR. miehei lipase preparation which is immobilized on a solid support as catalyst, although all three lipase preparations showed some catalytic activity under these conditions and, in addition, showed different kinds of selectivity for fatty acid and alkylamine chain lengths. No reaction was observed in similar experiments using one fatty acid as the substrate or one secondary amine.

Lipolysis of olive oil and tallow in an emulsifier-free two-phase system by the lipase from oat seeds (Avena sativa L.)

SummaryLipase activity from whole oat seeds is dependent upon calcium ion in a two phase olive oil-water system. No other tested ion can substitute for calcium. The lipolysis of melted tallow at 46°C was successfully conducted in the presence of calcium ion; the fatty acid fraction contained predominantly oleic acid.

Urethane foams from animal fats: VIII. Properties of foams from epoxidized tallow trimethylolpropane polyols

Polyols made by reacting trimethylolpropane with epoxidized tallow were converted to urethane foams by reaction with a polymethylene polyphenylisocyanate in the presence of fluorotrichloromethane. Adjusted with triisopropanolamine or an oxypropylated triamine to hydroxyl equivalent of either 100 or 120, the polyols yielded rigid foams of density 1.5–2.0 lb/ft3, open cell content 15–19%, and compressive strength 34–49 psi. These values were superior to those of similar foams from hydrated epoxidized tallow. Polyols made from epoxidized tallow-trimethylolpropane-HBr and adjusted to equivalent wt of 100 and 120 by triisopropanolamine gave foams whose small-scale flammability test samples burned less than 20% of their length. At hydroxyl equivalent 100, foams had density 1.6–1.8, open cell content 20–21%, and compressive strength 34–39 psi; in flammability tests burned <20% of length. The present foams were stronger than those made earlier from solvent-purified hydroxybrominated tallow. Formulation with half the normal amount of freon gave foams of higher compressive strength but lower flame resistance.

Urethane foams from animal fats: IX. Polyols based upon tallow and trimethylolpropane; preparation under acidic and basic catalysis

A series of polyols was prepared from epoxidized tallow, by reaction with trimethylolpropane in refluxing toluene, sequentially under basic and acidic catalysis. In preliminary experiments, under catalysis by sodium methoxide alone, the trimethylolpropane reacted rapidly with glyceride linkages and very slowly with oxirane groups. Under catalysis by p-toluenesulfonic acid alone, oxirane was rapidly consumed. Polyols were prepared by the following sequences: (A) reaction under acidic followed by basic catalysis; (B) reaction under basic followed by acidic catalysis; (C) reaction under basic catalysis followed by further treatment with HBr gas to introduce fire retardance; (D) treatment of whole tallow first with trimethylolpropane under basic conditions and secondly with bromine; (E) reaction of epoxidized tallow with diethanolamine under basic catalysis; and (F) treatment of epoxidized tallow first with trimethylolpropane under acidic conditions and then with diethanolamine under basic catalysis. The polyols described were adjusted to equivalent weights of 100 and 120 with added triisopropanolamine and treated with a polymeric isocyanate to give rigid foams. Densities ranged from 1.5–1.8 lb/ft3. Open cell content, for foams made at the equivalent wt of 100, ranged from 14–21%; at the equivalent wt of 120, from 17–27%. Compressive strengths ranged from 14–23 psi, being lower than those of the best previous epoxidized tallow-trimethylolpropane products.

Urethane foams from animal fats: X. urethane polyols from epoxidized tallow, trimethylolpropane, and propylene oxide1

A convenient three-stage reaction has been devel-oped for the preparation of polyols from epoxidized tallow (ET), trimethylolpropane (TMP), and propyl-ene oxide (PO), without the previously required water washing step. ET is first heated with excess TMP under catalysis by BF3, causing rapid ring open-ing of the oxirane function. In the second stage, KOH catalyzes ester interchange of TMP with the triglyc-eride. Finally, PO is caused to react with free TMP and with other available hydroxylic components, to produce a homogeneous mixture of polyols. The polyols, all liquid at room temperature, were adjusted to equivalent weights of 100 and 120 with added triisopropanolamine and reacted with a polymeric isocyanate in the presence of a blowing agent to give low-density rigid foams. Densities ranged from 1.6 to 1.8 lb/ft3 and compressive strengths from 21 to 30psi.

Rubber swell as a function of fatty acid ester chain length

A study was made of the relationship between the structure of some fatty acid esters of varying chain length and their swelling effect on standard nitrile rubber samples. The esters evaluated were: methyl esters of caprylic, capric, lauric, myristic, palmitic and isostearic acids;n-butyl, isobutyl,n-octyl, octadecyl, “tallow” and 2,2-dimethyl-1,3-propanediol esters of lauric acid and tetradecyl acetate. Federal test methods for aircraft turbine lubricants were used for the evaluations. In the esters the swelling was higher with type L rubber than with type H. The lower the equivalent weight of the ester, the higher the swell with both types of rubber. Branching in the alcohol moiety lowered the swell. Deswelling (desorption) in air of the swelled samples was also investigated. Methyl myristate, methyl palmitate and the long chain laurate esters meet MIL-L-23699 military specifications for type H rubbers. In type L rubbers the swelling is too high to meet specifications.

Direct esterification of sodiumcis-9,10-epiminooctadecanoate

Compounds containing the aziridine ring are known to have a tendency toward polymerization in the presence of mineral acids. Moreover, with aziridine derivatives of fatty acids, ring opening reactions are possible as a result of nucleophilic attack by generated carboxylic acids groups. It was found that high yields (86–89%) of methylcis-9,10-epiminooctadecanoate, with a minimum of attendant byproducts could be obtained by heating the corresponding sodium soap with methanol in the presence of certain acid catalysts under carefully controlled conditions. Temperature, duration of the heating period, and catalyst concentration were the variables studied for each catalyst. The catalysts evaluated were: boron trifluoride etherate, methanesulfonic acid, sulfuric acid, fluoboric acid andp-toluenesulfonic acid. Of these, for most laboratory preparations,p-toluenesulfonic acid is the catalyst of choice.