W. G. Bickford

A simplified method for the preparation of α- and β-eleostearic acids and a revised spectrophotometric procedure for their determination

SummarySimplified methods for the preparation of pure α- and β-eleostearic acids are described. These procedures involve saponification of α- and β-tung oils under mild conditions, followed by direct crystallization of the liberated acids at −20°C. from ethanolic solution. Only one recrystallization from ethanolic solution at +5°C. was required to produce the pure acids.Absorptivities obtained from measurements of the ultraviolet absorption revealed α-eleostearic acids of from 3–4% higher purity than those used in obtaining the equations previously recommended for the simultaneous determination of α- and β-eleostearic acids. This has necessitated a revision of these equations. Equations for the determination of each isomer from both cyclohexane and ethanol are reported. Equations are also given for an independent determination of total eleostearic acid, and for the determination of one isomer in the absence of the other.Infrared absorption spectra in the rock salt region from 2–15 microns have been measured from potassium bromide discs. These solid-state or crystalline spectra reveal, in addition to the prominent bands assigned to characteristic groupings of the eleostearic acid molecule, the progression bands by means of which carbon chain length can be computed.

Factors affecting the stability of crude oils of 16 varieties of peanuts

SummaryThe relation between fatty acid compositions, tocopherol contents, and autoxidative stabilities of a series of 16 crude oils from different varieties of peanuts has been investigated. It was found that the relative linoleic acid content of the oils is one of the major factors affecting the variations in the stabilities of the oils tested. With the exception of the oils from Runner peanuts the tocopherol compositions of the oils were not found to vary significantly, either in the nature and distribution of individual tocopherols, or in total tocopherol contents. The enhanced stability of the oils from the Runner peanuts may be due in part to the higher tocopherol contents of these oils. There is some evidence that crude peanut oils contain some non-tocopherol antioxidant and/or synergist.

Preparation of petroselinic acid

Petroselinic acid of a grade which is suitable for most laboratory applications has been prepared by a single crystallization of the mixed fatty acids of parsley seed oil from 90% ethanol. A product of higher purity has been prepared from this acid by application of urea segregation techniques for the removal of saturated materials. No evidence of the presence of unsaturated fatty acids other than petroselinic acid was found in either of these samples when their ozonolysis products were examined chromatographically. On the basis of iodine values, assuming the absence of other unsaturated materials, the purities of the two preparations are 96.0 and 99.4%.

Derivatives of jojoba oil as plasticizers for vinyl polymers and Buna-N rubber

SummaryTen maleinated jojoba oil derivatives were screened as plasticizers in a standard polyvinyl resin formulation and as softeners for Buna-N rubber. Three of these, the methyl and butyl esters and hydrogenated methyl esters of maleinated jojoba acids, were comparable to the reference standard, DOP, as primary plasticizers for the vinyl resin. Three others were satisfactory only as secondary plasticizers. Six of the derivatives were comparable to the reference softener, dibutyl sebacate, as softeners in a Buna-N formulation and yielded rubbers meeting the low temperature flexibility requirements (−40°C.) of the automotive industry. Two of the six, those made with the butyl and hydrogenated butyl esters of maleinated jojoba acids, met the still more stringent low-temperature requirements of the aircraft industry (−55°C.).In general, hydrogenation of a derivative adversely affected its compatibility in either the vinyl copolymer or the Buna-N formulations.

Improved procedure for cleaning glassware used in determining the stability of fats and oils by the active oxygen method

SummaryGlassware cleaned with a synthetic detergent instead of hot or cold chromic-sulfuric acid leads to improved reproducibility of the stability of fats and oils determined by the active oxygen method. When the glassware used in this method is cleaned with hot chromic-sulfuric acid, chromium compounds are absorbed within the glass walls and subsequently diffuse into the oil or fat thereby leading to erratic results. A method is described for cleaning the glassware used with the fat stability method which has given reliable results in the hands of the authors for more than a year, during which it has been in almost daily use.

Epoxidized jojoba oil as a stabilizer for vinyl chloride containing plastics

SummaryEpoxidized jojoba oil has been evaluated as a light and heat stabilizer for vinyl chloride containing plastics and its properties, intercompared with those of other epoxides representative of three major classes of oxirane stabilizers. The results obtained show that epoxidized jojoba oil is a satisfactory thermal and ultraviolet stabilizer for both TCP and DOP plasticized stocks and has no adverse effects on the plasticizer properties of these materials. In general, epoxidized jojoba oil was found to be equivalent to or, in some instances, superior to the other epoxides tested.

Plasticizer properties of methyl vinyl ketone-methylalpha-eleostearate adduct and derivatives

SummaryThe Diels-Alder adduct of methyl vinyl ketone and methylalpha-eleostearate was subjected to modification by hydrogenation and epoxidation of its unsaturated centers and by aromatization of its cyclohexene nucleus. These derivatives, as well as the original adduct, were intercompared with DOP as primary plasticizers for vinyl chloride-vinyl acetate copolymer. All of these materials were found to be highly compatible as primary plasticizers and generally more efficient than DOP. The stocks plasticized with the hydrogenated and epoxidized adducts exhibited very good thermal stability on long exposures to heat. The epoxidized adduct not only imparted excellent heat stability to the plastic but also prevented deterioration on exposure to ultraviolet irradiation.

The reaction of methyl vinyl ketone with alpha- and beta-eleostearic acids

SummaryMethyl vinyl ketone was found to be an active dienophile for the modification of the eleostearate

Tung oil derivatives as plasticizers for buna-N rubber

SummaryEight derivatives of tung oil, namely, the methyl vinyl ketone, dimethyl maleate, methyl acrylate, and acrylonitrile adducts, and their hydrogenated products, were prepared and screened as softeners for Buna-N rubber with dibutyl sebacate, as the control. Five of the eight products evaluated yielded stocks that met the low-temperature flexibility requirements (−40°C.) of the automotive industry. In all cases the stocks prepared from the unhydrogenated derivatives were superior in plasticizing efficiency to the stocks prepared from their hydrogenated counterparts or to those prepared from the control.

Divinyl sulfone-eleostearate adducts as plasticizers for nitrile rubber

Four divinyl sulfone-eleostearate adducts were synthesized and compared with dibutyl sebacate as plastieizers for nitrile rubber. Three of these, the adducts of methylalpha-eleostearate, its hydrogenated derivative, and that of tung oil, were found to be satisfactory primary plastieizers. The stocks prepared from the unhydrogenated adducts were superior in plasticizing efficiency to those prepared from their hydrogenated derivatives. The divinyl sulfone-tung oil adduct yielded a rubber which met the low-temperature flexibility requirements (−40°C.) of the automotive industry.