Isoparaffinic oils

The relatively recent development of isoparaffinic fractions from petroleum has resulted in experimental products of a very low order of toxicity to plant tissues. Initial studies have also indicated that selected isoparaffinic fractions are of a high order of toxicity to some insects or their eggs. The future development of isoparaffinic oils may result in new and important contributions to pest control on agricultural crops. 

This study is concerned with a single isoparaffinic fraction in the approximate distillation range of kerosene. Isoparaffinic oils are complex mixtures of saturated branched-chain compounds as illustrated by isopentane... 

Table I. Effect of Isoparaffinic Oil on Red Spiders and Certain Insect Eggs...

Comparisons were made with odorless kerosene and conventional summer tree spray oils. All applications in these studies were made to the point of runoff (200 to 400gallons per acre). As shown in Table II, emulsions of the isoparaffinic oil were safe at concentrations far in excess of the usual 1.5% maximum recommended for foliage sprays. 

SkeUand [83] was the first to utilize non-Newtonian liquids in the design ofELM. In this and related studies, the non-Newtonian LMs were prepared from Soltrol 220 (an isoparaffinic oil. Chevron Philips Chemical, Spring, TX, USA) as the diluent, polystyrene [81], polyisobutylene [74], and polybutadiene [80] as polymers, SPAN 80 as the surfactant and different aqueous solutions were used as stripping phases depending on the nature of the solute removed from the treated wastewaters [74]. SkeUand and Meng [80] studied the removal of benzoic acid, phenol and ammonia from simulated wastewater. 

Figure 11.17 Variation of C, C, C" and p with frequency for a suspoemulsion of 90% isoparaffinic oil in water emulsion and 10% polystyrene latex.

The relative viscosity-volume fraction curve for water-in-oil emulsions (42) is shown in Figure 12. Isoparaffinic oil (Isopar M) was used in this case and the emulsions were prepared using an A-B-A block copolymer of PHS-PEO-PHS (Arlacel P135, supplied by ICI PHS refers to poly-12-hydroxystearic acid and PEO refers to polyethylene oxide). 

The polarity of an organic molecule may be described by its dielectric constant or dipole moment. Oil polarity can also be related to the interfacial tension of oil against water yow example, a non-polar substance such as isoparaffinic oil will give an interfacial tension in the region of 50 mN m whereas a polar oil such as cyclomethicone gives yow he region of 20 mN m h The physicochemical nature of the oil phase determines its ability to spread on the skin, the degree of occlusivity and skin protection. The optimum emulsifier system also depends on the properties of the oil (its HLB number) as detailed in the chapter on emulsions. 

Sanyo developed Vl-improving agents with excellent low-temperatme performance [29]. These agents were a mixture of polymers of Cg i2 alkyl methacrylates with glass transition temperature (Tg) < 40°C, polymers of 0-90 mol% Ci-13 alkyl methacrylates, and polymers of 13-97 mol% Cm 24 alkyl methacrylates in weight ratios, 80-90 0.1-19.9 1-19.9. The agents were found to be useful for isoparaffin oils. 

Pig. 6. Typical stmctures in lube oil (a) / -paraffin, (b) isoparaffin, (c) cycloparaffin, (d) aromatic hydrocarbon, and (e) mixed aUphatic and aromatic ring... 

Fig. 4. Distribution of compound classes in cmde oils as a function of boiling point. Region A represents normal paraffins B, isoparaffins C, naphthenes ...

Within the VGO saturates, distribution of paraffins, isoparaffins, and naphthenes is highly dependent on the petroleum source. The naphthenes account for roughly 60% of the saturates in a normal cmde oil. However, samples can be found having paraffins from <20 to >80%. In most samples, the / -paraffins from C2Q—are still present in sufficient quantity to be detected as distinct peaks in gc analyses. Some cmde oils show a nearly symmetric pattern of peaks such that each carbon number is present in regular progression up to a maximum around C -j. Other cmde oils show a similar distribution, but have preference for odd-numbered alkanes. Both the distribution and the selectivity toward odd-numbered hydrocarbons are considered to reflect differences in petrogenesis of the cmde oils. Although / -paraffins are distinct in the gc, these usually account for only a few percent of the saturates measured by gc. 

Identification becomes more difficult in the case of isoparaffins since many structural isomers are possible with increasing carbon number. Nevertheless, all possible isoalkanes from through have been found in crude oils, along with several isomers of and some of Many isoprenoids (e.g., pristane and phytane) which serve as biomarkers to the genesis of petroleum have been detected in significant... 

Lower cloud point in the diesel fuel. Isoparaffins in the light cycle oil boiling range improve the cloud point. 

Brown and Huffman [85] reported an investigation of the concentration and composition of nonvolatile hydrocarbons in Atlantic Ocean and nearby waters. Sea water samples were taken at depths of 1 and 10 m and the nonvolatile hydrocarbons were identified by mass spectrometric techniques. The results show that the nonvolatile hydrocarbons in Atlantic and nearby waters contained aromatics at lower concentrations than would be expected if the source of the hydrocarbons were crude oil or petroleum refinery products. Hydrocarbons appeared to persist in the water to varying degrees, with the most persistent being the cycloparaffins, then isoparaffins, and finally the aromatics. 

Cottony Peach Scale Tests. Studies made on the cottony peach scale were limited, but the results obtained are considered reliable. All of the tests reported here were conducted in 1947 under orchard conditions. A heavily infested peach orchard at Hamlin, N. Y., was used for the experiment. Because the supply of the isoparaffins available was very limited, it was necessary to devise a procedure whereby satisfactory tests could be conducted with only 600 to 1000 ml. of spray mixture per test. Treatment was usually restricted in each test to two carefully selected attached branches 1 to 2 feet in length. A third branch was sprayed at the same time to provide leaves for oil deposit determinations. Treatments were applied on July 18 and 19, 1947. At this time all the eggs produced by the overwintering females had hatched, and the resultant new generation scales had largely moved to the leaves where they occurred on the lower surface along the midrib. A compressed air paint spray gun, operating at 30 pounds pressure, was used to apply the spray treatments. 

Additional studies were made of the oil as an insecticide and ovicide, when applied as an emulsion. In all cases the isoparaffinic fraction was solubilized by the addition of Triton B-1956, a nonionic phthalic glycerol alkyd resin. The emulsions were applied to the point of mnoff (200 to 400 gallons per acre). The results of these tests are shown in Table I. 

In tests performed in 1944, Crafts and Reiber (2) demonstrated that heavy isoparaffins (slightly heavier than mineral seal oil) are less toxic to barley than odorless kerosene. These workers also showed that heavy isoparaffins have little or no toxic effect upon Am-sinckia, Lactuca, and Stellaria species, or upon grasses. Heavy naphthenes, olefins, and aromatics were toxic, in ascending order, to these species. 

In the work here reported the relatively low phytotoxic qualities of isoparaffinic fractions were evident from the inception of the screening tests in 1945. In order to evaluate this characteristic more precisely, applications of the fraction previously described were made on the foliage of plants in the greenhouse and in the field, employing the oil at full concentration and at several dilutions in emulsion form. 

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