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INDUSTRIAL AND ENGINEERING CHEMISTRY
creases the dehydrogenation of ethyl alcohol a t the expense of the dehydration reaction. SOfar, no melt has been found that catalyzes the synthesis of hydrocarbons from carbon monoxide and hydrogen. Great difficulty is experienced in obtaining an ionic melt with suitable melting point and composition characteristics. More information on the degree of dissociation of fused salts is needed, because the choice of inorganic salts 1% hich are knon n t o form ionic mrlts is limited, and the effect of even small amounts of other salts in mixtures or eutectics is not known. LITERATURE CITED
Amos, J. L. (to Do%- Chemical Co.), C . 9. P a t e n t 2,140,500 (Dec. 20, 1938). Anderson. J., McAllister, S.H., a n d Ross, TV. E. ( t o Shell Development Co.), Ibid., 2,387,868 (Oct. 30, 1945). Bilta, W., and Klemm, JK, Z . unory. a l l y e m . Chenr., 152, 267 (1926). Bloom, H.. H a r r a p , €3. S.,a n d Heymonn, E., Proc. R o y . Soc. ( L o n d o n ) , A194, 237 (1945). Bloom, H . , and H e y m a n n , E., I b i d . , A188, 392 (1947). Cheney, H. A. (to Shell Development C o . ) , U. S. P a t e n t s 2,279,291, 2,279,292 (April 14, 1942) ; 2,342,073 (Feb. 15, 1944). Cheney, H. A, and hlchlillan, F. N. (to Shell Development Co.), Ibid., 2,394,898 (Feb. 12, 1946). E m m e t t , P. H., a n d Brunauer, S.,J. Am. Ciie~n.Soc., 59, 310 (1937). Gorin, E., F o n t a n a . C . M., a n d Kidder, G. A , IND. EXG.CHEM., 40, 2128 (1948). Grebe, J. J., Reilly, J. H., a n d Wiley, R. 31. (to Dow Chemical Co.), U. 8.P a t e n t 2,034,292 (March 17, 1936). Grimm, H. G . , Brill, R., H e r m a n n , C., a n d Peters, C . , h7aturwissenschaftcn, 26, 29 (1938). Guggenheim, E . A., Discussions Famdag Soc., No. 4, 317 (1948). Hanmer, R. S.,and Swann, S.,Jr., IND.ESG. CHEbr., 41, 325 (1949). Hinshelwood, C. N.,"Kinetics of Chemical Change," London, Oxford Press, 1940.
Vol. 43, No. 7
(15) Hudson, T. B . , a n d U p h a m , J. D. !to Phillips Petroleum Co.), U . S. P a t e n t 2,439,301 (April 6, 1948). (16) Johnson, P. C., and Sm-ann, S.,J r . . 1i-m. ENC.CHmr., 38, 990 (1946). (17) Johnstone, €1. F.,and TTinsche, W.E., Ibid., 36, 435 (1944). (18) Kimberlin, C. N. (to Standard Oil Development Co.), T.J. S. P a t e n t 2,268,401 (Dec. 30, 1941). (19) Levine, A. A , , a n d Case, 0. IT. (to E. I. d u P o n t de Xemours & Co.), Ibid., 2,154,049 (April 11, 1939). (20) McAllister, S. H., Cran-ford, C. C., and Ross, W.E. (to Shell Development Co.), Ibid., 2,417,698 (March 18, 1947). (21) AIott, N.F., a n d Gurney, R. W., "Electronic Processes in Ionic Crystals," 2nd ed., Xew York, Claretidon Press, 1948. (22) Mulcahy, M. F. R., and H e y m a n n , E., J . Phys. Chem.. 47, 485 (1943). (23) Palmer, \Ti. G., and Constable, F. H., Proc. R o y . Soe. ( L o n d o n ) , A106, 250 (1924). (24) Reilly, J. H . (to D o w Chemical Co.), U. S. P a t e n t s 2,140,448-51 (Dee. 20, 1938). (25) Ross, W. E., and Anderson, J. (to Shell Development Co.), Ibid., 2,327,670 (Aug. 24, 1944). (26) Ross, IT. E., and Carlson, G. J. (to Shell Development C o . ) , Ihid., 2,411,835 (Nov. 2 6 , 1946). (27) Sabatier, P., a n d Reid, E. E., "Catalysis in Organic Chemistry," Xew York, D. Van Nostrand Co., 1923. (28) Salstrom, E. J., J . Bm. Ciiem. Soc., 53, 3385 (1931); 54, 2653, 4252 (1932); 55, 1029, 2426 (1933); 56, 1272 (1934). (29) Salstrom, E. $J., a n d Hildebrand, J. H., Ibid., 52, 4641, 4680 (1930). (30) Shell Development Co. a n d Fife. J. G., Brit. P a t e n t 653,976 (June 11, 1943). (31) Steacie, E. W. R., a n d Elkin, E. &I.,Proc. R o y . Soc. ( L o n d o n ) , A142, 457 (1933); Can. J . Rasca~ch,11, 47 (1934). (32) Tiede, E., and Jenisch, W., Brennstof-Chem., 2, 5 (1921). (33) Vollmann, H., and Schacke, B. (to I. G . Farbenindustrie A&.), E.8. P a t e n t , 2:!61,645 (June 6 , 1939). (34) Wentier, R. R., Thermochemical Caloulatbnu," p , 24, New York, hlcGraw-Hill Book Co.. 1941. R B o E I V E n September 13, 1950. Presented before the Division of Industrial and Engineering Chemistry, Fifteenth Unit Process Symposium, a t the 118th sleeting of the &CERICAS C H E ~ C A SocIErr, L Chicago, Ill.
Protection of Paper and Textile Products from Insect Damage S. S. BLOCK Florida Engineering a n d Industrial Experiment S t a t i o n , Gainesville, Flu. Unlike the farmer who is constantlj- at war with insect enemies, the manufacturer of finished products often tolerates insect damage. AIore recently, however, manufacturers have shown the desire to correct this situation, provided practical solutions to their problems can be obtained. This work deals specifically with the prevention of the destructive activities of American cockroaches as applied to sized and glued textile and paper products and in the penetration of paper packages. It was found that starch sizing was much more difficult to protect than gelatin or gum arabic. Inert, waterinsoluble coatings of sufficient thickness prevented attack of sized surfaces. Of sixty-eight chemicals, only mercuric chloride and the alkali thiocyanates gave complete protection. Treating food-containing paper packages with saturated solutions of ammonium thiocyanate, ammonium nitrate, or magnesium chloride prevented penetration by starved roaches. Suggested as factors determining taste repellency were hygroscopicity, water solubility, ionic mobility, and specific chemical activity. In practical application, taste repellents may be recom-
mended where the use of insecticides is impractical or undesirable. Examples are in wrappers and containers for foods, and in sizings and glues for products that conie in direct contact with the person using them.
P
APER, textiles, glues, and inany other organic materials are vulnerable to attack by insects. Although it is difficult t o evaluate the annual cost of this insect damage, it is a serious problem, particularly in the warmer climates where insects are more abundant and active. I n recent, years there has been an increasing concern about this damage, and research workers have published studies ( 1 , 4-6,8, 10-14) of various aspeck of the problem. The work described in this report, deals with the prevention of the destructive activities of American cockroaches as applied to sized and glued textile and paper products and in the penetration of paper packages. Examples of roach damage (Figures 1 and 2) are familiar t.o those who have lived in the southern United States. Bottle labels, book coverp, wall paper, gummed tape, suitcase liners, sized documents, and food packages are some of the products which are susceptible to roach attack. Unlike the
July 1951
INDUSTRIAL AND ENGINEERING CHEMISTRY
termite, which attacks and digests the cellulose fiber itself, the roach feeds upon the sizing or glue on the fabric or paper, or punctures the container in search of food.
1559
OF SIZEDSURFACE WITH COATING TABLE I. PROTECTION MATERIALS
-
ProtectionLight coat, Heavy coat, 24 hours 72 hours Slight Complete None Complete Slight Complete
7 -
INSECTS
The American cockroach (Periplaneta arnericana) is a large insect and a heavy feeder, capable of doing extensive damage in a short time. This is the insect chiefly responsible for the type of damage shown in Figures 1 and 2. The American cockroach is much larger than other common roaches, being 1.5 inches long a n d 0.5 inch wide when fully grown. Although its destructive
Figure 1. Effect of Roach Feeding on Sizing of Bottle Label
Coating Nitrocellulose Nitrocellulose Cellulose acetate Ethylcellulose Methylcellulose Polyvinyl alcohol Vinylite Vinylite Shellac
Designation R.S., 35-see. S.S., 40-sec. High acetyl, medium low viscosity N-type, 20 cps.
... ....
Low viscosity, Type B VYNW 92% polyvinyl chloride AYAT polyvinyl acetate Orange
None None None
Complete None None
None None None
Complete Complete Complete
Another method investigated was the topical application of repellent chemicals in solutions or in a thin lacquer coating t o the surface. A quantity of solution was applied evenly over the surface of glass plates, and squares cut from book covers were inverted over them so that the solution could penetrate the sized surface uniformly. The repellents selected were relatively nonvolatile compounds of different chemical structure that might affect the taste of the sized surface and make it unappealing t o the insects. Because different sized surfaces were employed, their susceptibility to roach attack was determined and only those were employed which were completely defaced in 24 hours when treated with a weakly repellent chemical (2-naphthol) and unharmed when treated with a strongly repellent chemical (ammonium thiocyanate). Tables I1 and I11 present data for sixty-eight chemicals employed as taste repellents. With one exception, none of the lacquer coatings containing 16% of the chemical on a dry basis gave protection against the insects. Only mercuric chloride and the water-soluble thiocyanates had repellent qualities affording almost complete protection in these tests. The soluble but weakly ionized iron thiocyanate was also highly repellent. The insoluble copper thiocyanates were not effective. Tests of a number of organic compounds in which nitrogen and sulfur were in various structural combinations showed t h a t none of them had the high repellency of the inorganic thiocyanate.
:activity is chiefly during the summer months, it is able t o survive the mild winters of southern climates, such as Florida, and may be found outdoors or indoors all months of the year. The roaches employed for the work described here were captured locally in baited jars. They were unfed for a t least 2 weeks before testing was begun in order t o intensify their feeding activity. The tests were made in large crocks, greased a t the top t o prevent escape of the roaches. Approximately fifty insects were employed in each test. METHODS OF PROTECTING SIZED SURFACES
Table I presents data evaluating one method of protecting sized surfaces. This barrier treatment places a coating of an inert material between the attractive surface and the insect. Small squares, 0.75 X 0.75 inch, cut from book covers and having a sized surface readily attacked by roaches, were treated with light (0.0005 gram) and heavy,(0.0025 gram per sq. cm.) coats of different coating materials. As the table shows, the light coats gave practically no protection after 24 hours, whereas in most cases the heavy coats gave complete protection after 72 hours. Two exceptions were polyvinyl alcohol and methylcellulose which provided no protection at all. It is surprising t o find such different results with such closely related structures as methylcellulose and ethylcellulose. A property of the two ineffective materials not common t o the others was water solubility. Apparently, a coating t h a t the insect can dissolve or one so thin t h a t it can be easily penetrated does not ensure protection. Water-insoluble coatings of sufficient thickness, however, appear to discourage roach attack
Figure 2. Samples of Set of Fifteen Volumes Attacked by Roaches
The insecticidal chlorinated hydrocarbons could not be evaluated properly as taste repellents because of their insecticidal properties. With chlordan and hexachlorocyclohexane (benzene hexachloride, 98% gamma), some of the tests had to be terminated because too many insects were being killed by contact with the insecticidal surfaces in the small testing chamber. DDT did not afford protection, and chlordan and hexachlorocyclohexane were ineffective as repellents when applied in suspension as 16% of the lacquer. These insecticides undoubtedly have protective value in spite of their lack of repellency. Table IV shows the protection afforded by mercuric chloride and ammonium thiocyanate in different concentrations applied in alcohol solution and in lacquer. For equal protection higher concentrations were required in the lacquer. The lacquer apparently
I N D U S T R I A L A N D EN G I N E E R I N G CHEMISTRY
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Vol. 43, No. 7
TABLE 11. ROACH ATTACKOF SIZEDSURFACES AFTER TOPICAL TABLE 111. ROACH ATTACKOF SIZEDSURFACES TREATED WITH APPLICATION OF 5% SOLUTIONS L A C Q U E R COATIKG CONTAIXING 16 ASD 45% OF REPELLENTS -% of Surface AttackedRepellent Inorganic Mercuric chloride Ammonium thiocyanate Potassium thiocyanate Sodium thiocyanate Ferric thiocyanate Cupric thiocyanate Cuprous thiocyanate Cupric chloride Cupric sulfate Sulfuric acid Ferric chloride Zinc fluosilicate Potassium ferricyanide Potassium ferrocyanide Potassium cyanide Calcium chloride Lead nitrate Phenolics 2-Xaphthol Resorcinol o-Phenylphenol Sodium-o-phenyl phenate 2,4,5-Trichlorophenol 2,3,4,6-Tetrachlorophenol Pentachlorophenol Cu sic pentachlorophenate 6-&l orothymol
Tetrachloro-p-benzoquinone
2,3-Dichloro-1,4-na hthoquinone
2,2'-Dihydroxy-5,5%ichlorodiphen: ilmethane
p-Nitrophenol 2,4-Dinitrophenol Pjcric acid Salicylanilide Nitrogen-sulfur organics Thiourea A', N'-Dibutylthiourea N,N'-Diphenylthiourea 1-Naphthylisothiocyanate Tetramethylthiuram monosulfide Tetramethylthiuram disulfide Piperidine pentamethylene dithiocarbamate 2- Methylbenzothiagole 2-RIercaptobenzoth~azole 2-Benzothiaxolyl disulfide 2-Benzothiazol~~l thiobenzoate Dibenzothiazolyldimethylthiourea
N-Cyclohexrl-2-bensothiaaslsulfenamide
Phenothiazine Sulfamic acid Ammonium sulfamate Toluene sulfonamide Sulf ani1amide Sulfadiazine Sulfapyridine Miscellaneous organics Acetamide Acetanilide p-Bromoacetanilide Azobenzene N,N'-Diphenylguanidine 2-Methylbenzoxazole Quinine sulfate Diphenyl sulfone 4 4'-Dihydroxy di henyl sulfone tejt-Butyl-m-CresoPsulfide Triphenyl phosphate Dichlorodiphenyltrichloroethane(
24 hours
100
50 100 40
.. ..
95
100 95
.,
0 100 20
35
85 85 100 100
48 hours
100 90 100 90 100
100
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95
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45 100
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100
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--%
Repellent Inorganic compounds Mercuric chloride Ammonium thiocyanate Cupric chlofide Ferric chloride Zinc fluosilicate Ammonium fluoride Phenolicc; 2-Naphthol Resorcinol o-Phenylphenol Sodium-o-phenyl phenate 2.4,5-Trichloropheno1 2 3 4 6-Tetrachlorophenol P'e AtLchlorophenol 6-Chlorothymol Tetrachl oro-p-benzoquinone 2 3-Dichloro-1 4-na htho uinone 2:2'-Dihydrox$-5,5~dichl%odiphenylmethane Cupric pentachlorophenate Picric acid Nitrogen-sulfur organics N,N'-Dibutylthiourea N.iV'-Diphenylthiourea Sodium diethyl dithiocarbamate Tetramethylthiuram monosulfide Sulfanilamide Sulfapyridine Chlorinated hydrocarbons DDT Chlordan Hexachlorocyclohexane (12% gamma) Hexachlorocyclohexane (98% gamma)
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