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Curve 1indicates the results of 3 per cent of zinc oxide on the rubber, while Curve 2 shows the effect of the basic carbonate. No such high ultimate tensile strength is found with the basic carbonate, but the tensiles and elongations for the shorter cures are remarkably close together. By comparison with A of Fig. 1 the effect of basic zinc carbonate is readily apparent. Using basic zinc carbonate, the rubber becomes translucent in 30 min. at 141.5’ C. (the temperature a t which the cures represented in Fig. 4, were made), showing a rapid disappearance of the basic carbonate as such.
tolylguanidine and methylenedianilide it was thought that some effect of the unstable trithiocarbonate or dithiocarbamate might be shown. It was found that in low sulfur stocks, such as have been used throughout this work, an initial retarding effect is brought about unless the methylenedianilide is compensated for by an increase of sulfur sufficient to bring about its sulfur reaction. A mixture of methylenedianilide and di-o-tolylguanidine is less likely to “scorch” than when the guanidine is used alone in a highly compounded stock. To bring out the combined effect of di-o-tolylguanidine and methylenedianilide, the following stock was used:
METHYLENEDIANILIDE AND DI-O-TOLYLGUANIDINE I n the discussion of the chemistry of diphenylguanidine given above, it was stated that this compound reacts with hydrogen sulfide and carbon disulfide to form a trithiocarbonate. A number of accelerators, such as hexamethylenetetramine, anhydroformaldehydeaniline, and methylenedianilide react with sulfur to produce both hydrogen sulfide and carbon disulfide. By employing a mixture of di-o-
Vol. 15, No. 3
........ 100 ........... 3 ............... 3 0.4 ..... 0 . 5
Smoked sheet.. Zinc oxide.. Sulfur.. Di-0-tolylguanidine., ... Methylenedianilide
This formula is the same as that shown in F, Table I, in which 1 part of di-o-tolylguanidine has been replaced by 5 parts of methylenedianilide. Fig. 5 shows the tensile and elongation comparison of the two stocks.
T h e Beta-Chlorovinyl Chloroarsines”’ By W. Lee Lewis and G. A. Perkins NORTHWESTERN UNIVERSITY, EVANSTON, ILL.,
N a dissertation by J. A. Nieuwlandls there
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BUREAUOF SCIENCE, MANILA,P. I.
Following ts a reoiew of work. upon the absorption of acetylene by arsenic chloride in the presence of aluminium chloride. Further proofs of the structures and the physical properties of p-chlorooinyl diqhhloroarsine. bis-8-chlorovinyl chloroarsine, and tris-6chlorooinyl arsine, together with a theory of the mechanism of the absorption reaction, are presented. The methods of preparation, purification, analysis, and interconversion of the three chlorooinyl arsines are discussed.
appears the following paragraph : Pure arsenic chloride free from oxide did not show any reaction with perfectly dry acetylene. When aluminium chloride wasadded theabsomtion of the gas was effect;d with the evolution of considerable heat. The contents of the flask turned black. When decomposed by pouring the substance into cold water, a black, gummy mass separated out, and on standing for some time crystals appeared in the aqueous solution. The tarry substance possessed a most nauseating and penetrating odor and was extremely poisonous. Inhalation of the fumes, even in small quantity, caused nervous depression. No chlorine derivatives of acetylene were noted. Owing to the poisonous nature of the compound formed, their thorough investigation was postponed.
The importance of the substituted arsines in chemical warfare, together with the probability that there might be formed here one or more addition products of arsenic chloride and acetylene of a new order, led to a more careful investigation of Nieuwland’s reaction. I Received December 28, 1922. Published with the permission of Brigadier General Amos A. Fries, director of the Chemical Warfare Service. 9 The present paper is a partial report of an investigation carried out beween April l a and August 23, 1918, in Organic Unit No. 3, Offense Research Section, U. S. Chemical Warfare Service, stationed a t the Chemical Laboratory of the Catholic University of America, Washington, D. C The following men took part in the work in varying degree, and in the order listed: R. I,. Ginter, R. R . Williams, R. S. Bly, F. C. Vibrans, J. W. Rauth, W. N. Jones, W. T.Read, H. G. Seeley, G. 0. Gutekunst, H. R . Parker, H. P. Ward, R. A. Norton, 0. S. Levy, C. C. Curtis, Geo. Miller, Hugh Patterson, W. Hartman, H. R. Yon, Fred Cassebeer, F, C. Owens, E. W. Clark, H. W. Stiegler, P. F. Ziegler, C. W. Staples, J. A. Kerr, W. R. Crandell, E. M. Clarke, Alex Greenberg, F. 0. Krieger, E. Musser, L. L. Perry, G. F. Taylor, H. Abrams, R . 0. Davis. a Printed but not published. “Some Reactions of Acetylene,” p. 128, completed under direction of Dr. John J. Griffin a t the Catholic University of America in 1904.
PREVIOUS WORK
The addition of acetylene both with zation,and is recorded without by polymeriBaud,4 and a number of compounds of aluminium chloride, acetylene, and a third constituent, such as alcohol. have been isolated by Gangloff and Henderson.& Fischefl added arsenic chloride to the acids of the acetylene series, the addition of AsQ and chlorine taking place at the triple bond. Weak alkalies hydrolyze the chlorines attached to arsenic, yielding chloroarsenoso acids, which may be oxidized to the chloroarsono acids. Dafert? subsequently studied the reaction of acetylene upon arsenic chloride, and isolated a product to which he ascribed the formula AsCla.2CaHz. Dafert apparently regarded the substance as an association product rather than a secondary arsine, although the properties correspond to those of bis-p-chlorovinyl chloroarsine. He does not report finding the corresponding compounds of arsenic chloride with one and three molecules of acetylene, respectively. More recently Green and Prices have partially repeated and substantially confirmed the American work which had been reported in Chemical Warfare Communications in 1918. Lewis and StieglerQreported preliminary results on the derivatives of the chlorovinyl arsines, which work has subsequently been repeated and extended by Mann and Pope.l0 The authors and their collaborators reduced the reaction to controllable conditions, isolated three pure compounds from the reaction mixture, proved their nature, worked out methods of laboratory control, and submitted plans for large-scale production. In the later stages of the work J. B. Conantll and his to
Comfit. rend., 130 (1900), 1319. J . A m . Chem. Soc., 39 (19171, 1420. a Ann., 403 (1914), 106. 7 Monatsh., 40 (1919), 313. 8 J . Chem. Soc., 119 (1921), 442. a Science, 56 (1922), 55. 10.7. Chem. Soc., 121 (1922), 1754. 11 Chemical Warfare Communications, Organic Unit No. 1, Offeqse Rmearch Section, U. S. Chemical Warfare Service, 4
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laboratory also took up the chemical study of these substances, and to them we are indebted for the hydrochloric acid method of desensitizing original reaction mixtures, and for the first proof that the chlorine attached to carbon in the arsines is in the beta position, as well as other valuable details in processing.
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Pure arsenic chloride does not appreciably absorb acetylene. This we have found to be true at room temperature by comparing influent with efauent acetylene, and a t the boiling point and in vapor phase by testing the product. A mixture, however, of arsenic chloride and aluminium chloride absorbs acetylene readily a t room temperatures. The amount of the acetylene which can be thus absorbed is strictly limited by the amount of aluminium chloride present, although it also varies somewhat with other conditions that will be considered later. This limitation shows that the catalyst becomes converted into one or more products which are no longer active in producing absorption. The nature of a fresh reaction mixture seems to be best explained by the assumption that aluminium chloride first combines with acetylene and then with arsenic chloride to form an addition product, perhaps several addition products, but especially the one--A1Cls.3CZHZ.AsCl~. A probable structurc: is : c1
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