812
INDUSTRIAL AND ENGINEERING CHEMISTRY
TABLEVI. EFFECTOF LOADINGAGENTSON ANTIGELACTION Recipe Rubber Zinc oxide Sulfur Zinc dibutyl dithiocarbamate Polybutyraldehyde-aniline Whiting Magnesite Lithopone Titanium dioxide I-Chloro-1-nitropropane
100 5 3 0.5 0.5
100
... ... . ..
100 5 3 0.5
100
5 3 0.5 0.5
.0. ,. 5 .... .. ... 100 ... .. .
100
100
5 3 0.5 0.5
.0 ...5 ..... . *
*.
. .. 100
100
100
100
Gelling Time a t 50' C. 31 31 Without I-chloro-1-nitropropane,hr. 16 With 1-chloro-1-nitropropane, days Not gelled= a After 5 1 days.
31 35
22
100
100
5 3 0.5
51
.. . ...
100 22
Not gelleda
sprayed rubber for another. Some were milled 10 and some 15 minutes on a 6 X 12 inch laboratory mill with a roll tem-
Vol. 33, No. 6
perature of 140-150" F. (60-66" (3.). The benzene used in this series was redistilled and dried over calcium chloride. Table VI presents data showing the effect of various loading agents on the gelling of the cements and on the action of the antigel. It is apparent that many loading agents can be used in the presence of 1-chloro-1-nitropropane. However, various tests indicate that strong bases form complex salts with the antigel and thus destroy the value of the cement. For example, diphenylguanidine cements cannot be cured because of this salt formation. Lime and magnesia combine with the antigel and thus prevent its exercising any inhibitory action. The bonding power of the cements is not affected, although the rate of cure may be decreased somewhat by the retention of traces of the antigel in the film. PRESENTED before the Divlsion of Rubber Chemistly at the 97th Meeting of the Imerican Chemical Soclety, Baltimore, Md.
Distribution of Nicotine and Its Corn= Pounds between Water and Vegetable Oils L. B. NORTOK New York State Agricultural Experiment Station, Geneva, N. Y
The distribution of nicotine and several of its compounds between water and a number of vegetable and other oils has been determined at two concentrations in order to estimate the suitability of these combinations for insecticidal sprays. Most of the vegetable oils, particularly those with free alcohol groups, hold more nicotine than the mineral oils. The nicotine compounds give a less favorable distribution than free nicotine but tend to shift less toward the water with increasing concentration. The vegetable oils and a few of the nicotine compounds offer some advantage over mineral oil in the distribution of nicotine between the components of the spray, but this advantageis too small to be a deciding factor unless these materials show additional desirable properties.
PREVIOUS communication (8) reported the distribution of free nicotine between water and petroleum oils, and its application t o the behavior of insecticidal sprays. The same type of information seemed desirable for vegetable oils, which because of their more polar character might be expected to show a greater affinity for nicotine than the mineral oils, and therefore t o hold a greater proportion of nicotine in competition with water. The limited information available on the insecticidal properties of the vegetable oils indicates that some of them may compare favorably with mineral oils in ovicidal effect and in safeness to foliage. It is therefore of interest to determine whether they possess any distinct advantages in a spray mixture, or a t least whether they may be substituted without loss of efficiency in case of high prices or limited availability of mineral oils.
A
Procedure One or more examples of each of the main types of vegetable oil were chosen. Pine oil was included because of its solvent properties, and neat's-foot, fish, and a medium petroleum oil were included for comparison. A sample of each oil was titrated with 0.1 N sodium hydroxide as a test for rancidity and acidic impurities. The acid numbers are included in Table I. None of the acid numbers appear seriously higher than those to be expected in fresh oils. The nicotine was purified by the method of Rata (3) as in the previous work on distribution. I n addition to free nicotine, a number of oil-soluble nicotine compounds were included in the-present work because of the lower volatility of the compounds and the possibility of a greater affinity for the oil because of structural similarity. These compounds were made by direct mixing of nicotine with the calculated amount of pure acid. The naphthenate was made from naphthenic acid furnished by the Shell Oil Corporation, purified by steam distillation, and titrated t o determine its effective equivalent weight. The technique for the determination of the distribution ratios was the same as that used in the previous distribution work, gravimetric analyses being made throughout. Tests showed that the nicotine was quantitatively extracted from the oil by hydrochloric acid even in the presence of oilsoluble organic acids. The distribution was determined at only two concentrations, 0.1 and 5 per cent, which represented approximately the concentrations to be expected in a spray mixture soon after application and a t the time of near dryness, respectively. The ratios determined a t the 0.1 per cent concentration of the compounds represent only approximately the distribu-
June, 1941
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
813
pounds with free alcohol groups, which may account for their improved solvent properties. WATERAND OILS AT 25’ C. The rest of the vegetable oils show no great Concn. of Nicotine in Water/Concn. in Oil differences. In general, the drying properties of Acid NO., Alkaloid Oleate Naphthenate Stearate, the oils appear to have no significant effect on the Oil Mg.KoH’ Gram 0.1% 5% 0.1% 5% 0.1% 5% 0.1%. distribution ratio; this indicates that the degree Drying Oils of unsaturation of the fatty acids has little ef1.30 1.13 1.68 0.70 1.20 0.51 0 . 7 6 Linseed 4.78 fect on the solvent power of the corresponding 0.94 0.96 1.02 0.74 0.54 4.32 0.50 0.81 Sunflower-seed 1.66 0.63 1.02 0.98 0.65 0.48 0.47 0.79 Soybean fats for nicotine. The amount of free fatty acid 0.45 1.27 1.20 0.69 0.85 0.71 0.73 Tung 4.76 1.02 1.12 1.11 0.62 0.51 0.89 0.65 0.51 Poppy-seed in the oils is also of little influence. The two Semidrying Oils animal oils tested showed results very similar 0.80 0.83 1.05 0.95 0.63 0.28 0.36 0.61 Cottonseed to those of the vegetable oils. However, with 1.14 1.15 1.20 0.72 0.38 0.92 0.51 Corn 0.22 few exceptions the vegetable oils hold nicotine and 1.35 1.41 0.90 0.42 1.03 1.38 1.03 0.71 Rapeseed 0.95 1.11 1.16 0.68 0.39 0.39 0.86 0.59 Sesame its compounds better than does mineral oil. The Nondrying Oils average distribution coefficients for the vegetable 0.98 1.12 1.26 0.80 0.39 0.38 0.99 0.59 Peanut oils are decidedly lower than those for the mineral 0.77 1.11 3.20 0.41 0.91 1.07 0.43 0.41 Olive 0.31 0.27 1.23 0.28 0.33 0.48 0 . 2 8 0.31 oil, as shown in Table I. Castor 0.51 0.21 0.49 0.14 0.34 0.20 0.11 0.39 Pine The manner of combination of the nicotine Animal a n d Mineral Oile shows a greater influence on the distribution Neat‘s-foot 10.70 0.33 1.15 0.64 1.15 1.60 1.00 0.66 than does the composition of the oil. The reFish 7.28 0.78 1.10 1.42 0.74 Petroleum i:ii 1.77 o:is 1.34 1.52 1.59 o:a7 sults with the compounds confirm the preliminary Av. (omitting castor, experiments mentioned in the previous paper (B), pine, a n d petroleum) 0.44 0.88 0.95 1.13 1.29 0.73 0.64 which show that nicotine salts, even though oil The stearate has a solubility of less t h a n 5% in most of t h e oils. soluble, tend to favor the water more than does free nicotine. The ionization and hydrolysis of the compounds are apparently sufficient to tion in an actual spray mixture, because the different hycounteract the oil solubility. An increase in the chain drolysis products are unequally distributed between the phases length in the fatty acid salts appears to reduce their solubility and lead to somewhat different results with different relative in the oils as well as in water. Nicotine salts of strong acids, amounts of oil and water. However, no appreciable error is such as sulfuric or sulfonic acids, remain practically comintroduced with free nicotine alone a t either concentration, pletely in the water, as mentioned above. The different and the 5 per cept concentration of each material represents compounds show considerable variation in their behavior a t fairly closely the conditions in the field when nearly all of different concentrations. The average values in Table I the water has evaporated from the spray residue. show that the distribution ratios of free nicotine increase Another source of error lies in the incomplete separation of greatly with increasing concentration for all of the oils, those the two layers. Some of the oils tended to form quite stable of the oleate increase slightly, and those of the naphthenate .emulsions, especially in the presence of nicotine compounds decrease strongly. A decrease a t higher concentrations showing surface activity. In some cases a clean separation should aid in the transfer of nicotine to the oil on evaporation was impossible, even with a long period of centrifuging. of the water and therefore in the retention of the nicotine for This difficulty probably accounts for some of the apparent a longer period. “differencesbetween oils of very similar composition. Although the vegetable oils show a definite advantage over the mineral oils in their retention of nicotine in competition with water, it is questionable whether the magnitude of the Distribution Ratios difference is sufficient to give a significant effect in the field. The distribution ratios found for nicotine and its oleate, The same consideration applies to the concentration effect naphthenate, and stearate between water and the different with the compounds, the slight advantage of which would be .oils are presented in Table I. The designated percentages of value only if coupled with other desirable properties. That represent the concentration of nicotine in the mixture as a such might be the case is indicated by the high contact whole. toxicity of the fatty acid salts compared with that of free A number of determinations were made with nicotine nicotine (1). With hard water, however, these salts would .compounds and oils other than those appearing in Table I. require an excess of the fatty acid or a treatment of the water Nicotine linoleate was tried with several typical oils, with to prevent their decomposition. The ovicidal properties results so similar to those obtained with the oleate that the and the safeness to foliage of the vegetable oils are now .complete series was not run. Nicotine cerotate and a being tested to determine whether they have any advantages nicotine “resinate” proved to be incompletely soluble in most over the mineral oils other than the relatively small distribuof the oils even a t the lower concentration. Nicotine sulfate tion effect. and nicotine “aresket”, a sulfonate, were found completely in the water phase, as might be expected from their highly Acknowledgment ionized nature. A chlorinated paraffin behaved toward nicoThe author wishes to express his appreciation to M. W. tine about the same as the average vegetable oil. A sample Baker for his assistance in the analytical work. of blown rapeseed oil gave a ratio of 1.30 with 5 per cent nicotine. Literature Cited Two of the oils are outstanding in their effect on distribution-pine and castor. Pine oil was by far the most effective (1) Hansberry, Roy, and Norton, L. B., J . Econ. Entomol., 34, 80 of those tested. From a practical standpoint, however, this (1941). (2) Norton, L.B..IND.ENQ.CHEM., 32,241 (1940). oil is eliminated because of its volatility. The castor oil is (3) Ratz, F.,Monatsh., 26, 1241 (1905). not so outstanding as the pine, but it shows a consistently lower distribution ratio than any of the others. These two APPROVED b y the Director of t h e New York State Agricultural Experiment .oils are the only ones containing a large proportion of comStation for publication as Journal Paper 398. RATIOS OF TABLE I. DISTRIBUTION
Q
NICOTINE AND
COMPOUNDS
BETWEEN
