E. W. Bell

Sperm oil replacements: Synthetic wax esters from selectively hydrogenated soybean and linseed oils

Abstract and SummarySynthetic wax esters with properties similar to those of sperm whale oil have been prepared entirely from soybean and linseed oils. the synthesis required: (a) selective hydrogenation of the oils with copper-on-silica gel catalyst, (b) hydrogenolysis of fatty acids to fatty alcohols with copper-cadmiumchromium catalyst, and (c) esterification of hydrogenolysis products to yield predominantly long chain fatty esters which contained unsaturation in both the alcohol and acid moieties. Similarity of physical and chemical properties indicate that these wax esters are possible replacements for sperm oil. After sulfurization, the wax esters also have potential as extreme pressure lubricant additives.

Potential synthetic lubricants: Esters of C18-saturated cyclic acids

A series of 16 esters of C18-saturated cyclic acids (HCal) were prepared, and partial evaluation showed that several have qualities that recommend them as potential low-temp lubricants. Starting materials used were primary, straight, and branched chain alcohols C4–C7; perfluoro alcohols; phenol; cyclohexanol; and C18-saturated cyclic alcohols prepared from cyclic acids. Viscosities were measured at −40, 100, and 210F. Their viscosity indexes ranged from 26 to 143. Pour points or melting points of the esters ranged from −27 to −96F. The oxidative stability of these esters measured at 347F according to a modification of the test method for military specification MIL-L-7808 was in nearly all cases equal or superior to the control bis-2-ethylhexyl sebacate. More severe oxidation tests showed the esters of HCal to be slower than the control in the development of acidic decomposition products.

Methods for improving yields of cyclic acid from linseed oil

Liquid C-18 saturated monocarboxylic acids, which are termed “cylic acids” because they contain a ring structure, have been prepared by the action of excess sodium hydroxide on linseed oil in ethylene glycol at elevated temperatures, followed by distillation and hydrogenation of the resulting free fatty acid monomers and by separation of the straight-chain components by low-temperature crystallization from acetone. In a survey of other possible catalysts and reaction conditions, cyclic acid yields were improved from the previously reported 32.4 g to 43.5 g of cyclic acid per 100 g of linseed fatty acids by removing water from the starting materials and using the monosodium derivative of ethylene glycol as catalyst. The corresponding amount of polymer formed decreased because of a decrease in hydroxylation and subsequent polyester formation.

Potential lubricants for continuous casting of steel: polyol esters of partially hydrogenated soybean acids

In the past decade continuous casting of steel into billets and slabs without going through the ingot stage has drawn widespread attention in the steel industry. Mold lubrication is vital to continuous casting to prevent sticking. Approximately 50% of this operation uses a vegetable oil lubricant, primarily rapeseed oil. Trimethylolethane, trimethylolpropane, trimethylolbutane and pentaerythritol esters of partially hydrogenated soybean fatty acids, derived from commercially hydrogenated soybean oils, have been readily prepared in good yields. Preliminary measurements of viscosities, smoke, flash and fire points of these polyol esters indicate that they are possible candidates for use as lubricants in the continuous casting of steel.

Sperm Oil Replacements from Selectively Hydrogenated Soybean and Linseed Esters: Special Lubricants

Soybean and linseed oils were selectively hydroenated with copper-on-silica gel catalyst. The linolenate content of the oils was reduced to diene and monoene with no appreciable increase in saturates. Hydrogenated soybean oils contained 68–76% monoene, 11–18% diene, 0% conjugated diene and triene, 1–6% conjugatable diene, 0–0.3% conjugatable triene, and 23–40% isolatedtrans double bonds. Hydrogenated linseed oils contained 44–54% monoene, 35–45% diene, 0% conjugated diene and triene, 0–7% conjugatable diene, 0–02% conjugatable triene, and 44–59% isoaltedtrans double bonds. Esters of fatty acids, derived from these selectively hydrogenated oils, were prepared with trimethylolethane, trimethylolpropane, trimethylolbutane, pentaerythritol, ethylene glycol, C18 saturated cyclic alcohols, primary C12–C18 saturated (nC12, nC14, nC16, nC18) alcohol, and primary C16–C18 saturated (nC16, nC18) alcohol blends. Measurements of viscosities and of smoke, flash, and fire points indicate that these esters are possible replacements for sperm oil. Certain of them, after sulfurization, also have potential as extreme pressure lubricant additives.

Reactions of dienophiles with vegetable oils. I. Reactions of maleic esters with sulfur dioxide catalyst

SummaryDirect reactions of dibutyl and dimethyl maleate with safflower oil were investigated. When transformed into esters and distilled, the products are generally different from the Diels-Alder adducts obtained fromtrans,trans-9,11-linoleic acid. The differences most probably result from the formation of one or more isomers of the known product, of the substituted succinate, of a transannular lactone, or of a mixture of these and other isomers. No definite assignments of structure can yet be made. In one experiment the Diels-Alder adduct was obtained as the major product from the reaction of dimethyl maleate with safflower oil.Reactions are best carried out by heating safflower oil to 290° while sweeping it with sulfur dioxide. The maleic ester is then added dropwise, and the product is transesterified and distilled. By this procedure a distillable adduct fraction is obtained in yields up to 70%, based on linoleate. Fumaric esters give similar results. Omission of the sulfur dioxide catalyst greatly reduces the yield.

Preparation of alcohols from cyclic fatty acids

Saturated C18- and C20-cyclic alcohols have been prepared by catalytic hydrogenation of methyl esters from cyclized linseed monomeric acids, purified saturated C18-cyclic acids, ethylene adduct of conjugated soybean fatty acids, and ethylene adduct of conjugated octadecadienoic acids. The cyclic alcohols have also been prepared from free acids of crude cyclic linseed, cyclic linseed monomeric, and ethylene adduct of 9,11,t,t,-octadecadienoic. Conversion of esters and acids was 88–99% by hydroxyl determination; by gas-liquid chromatographic analysis, almost quantitative Hydrogenations were carried out with 10%, by weight, copper chromite catalyst, an initial hydrogen pressure of 2,100 psi, and a temperature of 280C for 3–5 hr.Preliminary evaluations indicate that saturated C18- and C20-cyclic alcohols have a potential use in cosmetic formulations.

Drying oils from xylitol

SummaryEsters of xylitol with linseed and soybean fat acids were prepared. An average of four of the five hydroxyl groups in xylitol could be esterified, one group being lost by dehydration. These esters were evaluated in paints. Although thixotropy and crawling were objectionable in the soybean ester paints, the speed of drying and loss of residual tack were superior in comparison to the corresponding properties of paints containing only soybean oil as the vehicle.

Ethylene adduct of conjugated octadecadienoic acids: III. Aromatization of C20 cyclohexene methyl esters

A procedure is described for the catalytic aromatization of the ethylene adduct of conjugated isomers of methyl octadecadieonate. When the C20 cyclohexene fatty methyl esters were heated at 290–300 C with palladium and 1-octadecene as hydrogen acceptor, C20 aromatic cyclic esters were obtained in 90–95% yield.

1,2-Cycloaddition of Haloalkenes to Conjugated Fatty Esters

We have studied the reaction of 1,1-dichloro-2,2-difluoro-, chlorotrifluoro-, and tetrafluoro-ethylenes and also hexafluoropropylene withcis,trans andtrans,trans isomers of conjugated methyl octadecadienoate. Reactions gave 50-82% yields of cycloaddition products. The pre-ponderance of products with a cyclobutane struc-ture and a double bonda,β to the cyclobutane ring was shown by IR and NMR spectra.Reactions were carried out in diluent with hy-droquinone inhibitor at autogenous pressure and a temperature of 200C for 5 hr. The distilled adducts are colorless liquids with viscosities rang-ing from 11 to 19 centistokes at 100F. These products and their hydrogenated derivatives ex-hibit low pour points (down to -76F) and may be useful as low-temperature plasticizers or lubricant additives.