(9V) Selvaraj, R. J., Susheela, T. P., Clin. Chim. Acta, 27, 165 (1970). (1OV) Tibbling, G., ibid., 23, 209 (1969). Supplamenl
(1) Remp, D. G., Stand. Methods Clin. Chem., 6, 1 (1970).
(2) Kaplan, A.,Savory, J., ibid., p 13. (3). Bowers, G. N., Jr., McComb, R. B., abad.,D 31. (4) Klein, L., ibid.,p 41.
(5) Fernandea, A. A., Jacobs, S. L., ibid., p 57. (6)Nobel, S., ibid., p 73. (7)Goodwin, J. F., ibid., p 89. (8) Sunderman, F. W., Jr., ibid., p 99. (9) Jacobs, S. L., Fernandez, A. A., ibid., p 107. (10) Kingsley, G. R., Tager, H. S., ibid., p 115. (11) Klein, G. C., Cooper, G. R., ibid., p 127. (12) Lanchantin, G. F., ibid., p 137.
(13) Sax, S. M., Moore, J. J., ibid.,p 149. (14) Cooper, G. R., McDaniel, V., ibid., p
, rn lay.
(15) Gambino, S. R., ibid., p 171. (16) McNair, R. D.,ibid., p 183. (17) Pybus, J., Bowers, G. N., Jr., ibid., n 189.
Coatings M. H. Swann, M. I. Adams, and G. G. Esposito, U.S. Army Coating and Chemical laboratory, Aberdeen Proving Ground, Md.
T
HIS BIENNIAL REVIEW covers the period from January 1969 through December 1970 and includes the authors’ choice of important contributions t o the analysis of coating materials that have appeared since the previous summary (102). It is hoped that the attempt to be selective has not caused omission of commendable contributions. Other reviews of general (82) and specific nature were made within this period, and a monthly index to coatings literature is published in each issue of Paint Technology from a review of 26 journals on coatings and includes reference to articles on analysis. A number of books on various phases of polymer analysis have been published in this two-year period, most of which are of special interest to the coating analyst. Myers and Long (79) have edited volume 2 of the Treatise on Coatings, in which each chapter treats separate physical techniques for coating characterization. T h e analysis of both raw materials and finished surface coatings are included and the applications of gas chromatography, thermal analysis, microscopy, and spectroscopy are discussed in separate chapters. A 456-page book containing 740 infrared spectra was published (16) b y t h e Chicago Society for Paint Technology. Stevens published a 198-page book (99) on polymer analysis b y gas chromatography, which was intended t o serve as a n up-to-date monograph on the subject. Although the bibliography contains 380 references, the application of gas chromatography to drying oil analysis was omitted. The final chapter of the latest book in the series of monographs on chemical analysis, “The Analytical Chemistry of Nitrogen and its Compounds’’ (101) concerns nitrogen polymers. It contains a number of procedures for analyzing cellulose
nitrate, amino-formaldehydes, acrylonitrile, polyamides, polyurethanes and other synthetic polymers. Other books have appeared on such subjects as X-ray diffraction methods ( I ) , polymer characterization (10), analysis of polyurethanes (22), infrared spectra and structure of long chain polymers (26), adhesive and coating testing (SI), infrared analysis of polymers, resins and additives (47), and the chemical analysis of plastics (61). GENERAL ANALYTICAL SCHEMES
T h e application of thermal methods of analysis to organic coatings was discussed by Holsworth (46). T h e characterization and identification of some film-forming polymers b y differential scanning calorimetry was described (43). Yeagle (122) illustrated the qualitative and quantitative analysis of polyester resins with nuclear magnetic resonance spectra for eleven polyols, nine acids, and eight known polyester systems. Scott (94) published a paper on the application of X-ray diffraction in the paint industry, pointing out its usefulness in quality control of finished products as well as individual pigments. The application of X-ray emission analysis to pigmented paint samples in the form of dried thin films was investigated (70) and several elements such as titanium, lead, and calcium were determined in a single sample preparation. Other applications of X-ray emission analysis were presented (16) in which samples in solid, liquid, and powder form were included. Two foreign publications (6, 57) reported the use of thin-layer chromatography for identifying acids and polyols in some coatings and for determining compositional uniformity.
Valero (110) discussed the analysis of paints in general by a variety of methods and included 102 literature references. A general discussion of the applications of infrared spectrophotometry to coatings was published (10.4). Low and hIark (68) studied a variety of clear and opaque coatings on steel and glass by infrared interference spectroscopy, and discussed (69) the principles involved in examining a number of clear metal coatings by infrared Fourier transform spectroscopy. &‘ithers (120) outlined the application of internal reflection spectroscopy t o coatings. Sherwood (95) explained his technique for combining micro-pyrolysis with infrared spectrophotometry t o identify wire enamels using l/Z-inch lengths of wire. Three foreign publications dealt with compositional analysis b y a combination of pyrolysis with gas chromatography. Hagen (38) used both gas and thinlayer chromatography to examine such polymers as poly(viny1 chloride) , polyurethanes, nitrogen resins, phenolics, and poly(methy1 methacrylate). Sonntag (97) made experimental comparison of three different techniques for pyrolyzing three polymers and Audebert (4) reviewed the progress made in gas chromatographic analysis of polymers for t h e period 1954 to 1967. Another review (86) was made of the applications of gas chromatography in the paint industry and included solvent, oil, resin, plasticizer, polymer, and emulsion analysis. A paper was published (77) on t h e application of trimethylsilylation and gas chromatography to the determination of the composition of polyamide resins. T h e use of gel permeation chromatography for quantitatively analyzing moisture-cure polyurethane coatings was illustrated (59) in which the commercial coatings were
ANALYTICAL CHEMISTRY, VOL. 43, NO. 5, APRIL 1971
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fractionated into solvent, free diisocyanate, and prepolymer. SPECIFIC CLASSES O F HIGH POLYMERS
A method and apparatus were described (56) for determining the structure of anticorrosive polyurethane coatings based on infrared spectra of compounds present as thin layers on the reflecting surface. Gedemer (33) reviewed the methods of analyzing epoxy resins in a n article discussing chemical, thermal, chromatographic, and spectrophotometric methods for characterizing the resins. Chemical methods for epoxy resin analysis were published by Ulbrich (108). Wiesner (118) used reversed phase chromatography t o analyze commercial epoxy resins. Infrared analysis was used (105) to determine the phenolic ingredients in cured phenolic-epoxy systems and included the identification of p-phenylphenol, phenol, cresol isomers, bisphenol A, and alkyd phenols. Reaction products which formed during the manufacture of phenol-formaldehyde resins were identified by gel-permeation chromatography (87). The qualitative analysis of phenol- and cresol-formaldehyde resins was accomplished by pyrolysis combined with gas chromatography (107) and it has also been applied t o the analysis of acrylic and methacrylic ester copolymers (24). Polarographic analysis was utilized (7) for separate determinations of acrylates and methacrylates in mixtures. The near infrared region was used (34) t o determine the styrene content in copolymers with aliphatic acrylates, and a new method was claimed (48) for verifying copolymer formation of butadiene-styrene. The latter method was based on separation of homopolymers, if present, b y use of a two-layer solvent extraction. Post (84) supplied two methods for determining quantitatively the styrene-butadiene and styrene-acrylate resins in solvent-type paints used for masonry and traffic paint. Micro-beads in column chromatography have been used (8) t o fractionate acrylic and vinyl acetate emulsions and also rubber and vinyl acetate emulsions. A multiple isothermal degradation method was described (62) for determining combined vinyl acetate in vinyl acetate-ethylene copolymers. Hillman and Wells (42) detected etch primers in paint flakes by pyrolysis and gas chromatography from the butyraldehyde formed from poly(viny1 butyral) binder. It was illustrated with pyrograms of various types of coatings, with and without the etch primer present. Willerns (119) detected urea-, melamine-, and benzoguanamine-formaldehyde resins in paint binders b y thin-layer chromatography following acid hydrolysis. Two papers 42 R
appeared on the analysis of polyimide wire lacquers; Hummel (46) examined four types by infrared spectroscopy and McGowan (71) used attenuated total reflectance to determine the degree of cure of these coatings. T h e ultraviolet spectra of 15 natural resins and gums were recorded for identification purposes (18). Helm (40) studied the effect of using liquid-liquid chromatography preceding liquid-solid chromatography to enhance the separation of asphaltic materials. SPECIFIC CONSTITUENTS
Two papers appeared in this period for determining the polyhydric alcohols in oils and alkyd resins. I n both techniques the alcohols were released from the resins by aminolysis, but in one (30) the trimethylsilyl derivatives were formed and chromatographed and, in the other (20) they were esterified with acetic anhydride and chromatographed. Stanley and hfoseley (98) published a method for determining combined maleic anhydride in rosinmaleic anhydride adducts by chromatography t h a t was based on separation of the rosin acids from the adduct on a column of silicic acid and celite. A procedure for determining the individual contents of sebacic and maleic acids in polyester resins (123) was based on the saponification of duplicate samples, titration of one for total acid content, and formation of insoluble zinc sebacate on the other. Katnik (65) used gas chromatography to analyze isomers of toluic acid through formation of trimethylsilyl derivatives. Ethoxyl groups in ethylcellulose and ethyl hydroxyethyl cellulose were measured b y the acetic acid formed by oxidation, using gas-liquid chromatography for the separation (4g); in a separate method, the groups were calculated from the weight of carbon dioxide formed on decomposition with hydriodic acid (96). The functional groups in butylated melamine-formaldehyde resins were measured (126) in order to study the reactivity of the resins with alkyds of varying hydroxyl value, and methods for nitrogen content, formaldehyde, methylol groups, and amine groups were explained but not supplied in detail. A micro-titrimetric method for the determination of oxirane functional groups in seed oils (14) used quaternary ammonium halide and perchloric acid. The carboxy group content of copolymers has been estimated (93) by an infrared absorbance-ratio method using bands a t 5.88 pm and 10.98 pm. Zimmerli (124) measured the acid value of alkyd resins by automatic weighing of sample and titrant. The double bonds derived from fumarate in copolymers of un-
ANALYTICAL CHEMISTRY, VOL. 43,
NO. 5, APRIL 1971
saturated polyesters have been de( I 14). termined polarographically Norton, Turner and Salmon (81) reacted epoxy resin samples with lithium aluminum hydride in a specially designed reaction vessel to determine hydroxyl group content from the hydrogen released; the hydrogen was measured by gas-liquid chromatography. A procedure was described (IS) for determining the number and the nature of the end groups of poly(viny1 chloride). A coulometric bromimetric titration technique was supplied (63) for measuring the vinyl acetate monomer in aqueous dispersions of poly(viny1 acetate). A gas-liquid chromatographic method was used (28) t o determine the acetate content of polymer materials and was applied to vinyl chlorideacetate copolymers and also to cellulose acetate resins. Truscott (106) used the Schoniger oxygen flask and atomic absorption spectrometry to determine chlorine in poly(viny1 chloride) ; X-ray excitation has also been used (67). Cook, Jones, and Altenau (19) determined 5-500 ppm. of such metalb as chromium, manganese, iron, cobalt, nickel, copper, and zinc in polymers by X-ray fluorescence. Absorption in the ultraviolet region after reaction with salicylic acid was used (78) to measure the nitrate content of esters such as nitrocellulose. Anderson and Tessari (3) combined analytical chemistry with instrumentation to determine the composition of electrocoating baths and supplied methods for determining nonvolatile, pigment-to-binder ratio, acid value, amine equivalence, amino resin content, antioxidants, and solvents. Vinson (113) used a dipolar aprotic solvent to accelerate the reaction between isocyanate and the reagent dibutylamine. I n some compounds, the reaction time was reduced from one hour to ten minutes and this could be useful in the analysis of urethane polymers. Two sampling devices were illustrated (103) for removing small samples of coating material from aerosol spray cans and a technique for determining the nonvolatile content was supplied. Kellum and Uglum (64) titrated the hydroxyl groups attached to silicon in monomeric and polymeric silanols and in some silicone resins using lithium aluminum dibutyl amide as a direct acid-base titrant. Wetters and Smith (116) determined the silicon in siloxane polymers and silicon-containing samples b y employing alkali fusion decomposition; the silicates formed were measured spectrophotometrically. OILS AND FATTY ACIDS
A textbook of 524 pages on the analysis of fats was authored by Wolff
(121) t h a t includes various spectrophotometric, chromatographic, and potentiometric methods as well as classical techniques. Herb and Martin (41) analyzed 13 oils and two mixtures t o study the relative degree of difficulty of analytical methods and compared the precision of results obtained by two different detectors, thermal conductivity and flame ionization. I n order t o quantitatively separate saturated and unsaturated fatty acids of the same chain length b y gas chromatography, a procedure was described (25) that utilized formation of trimethylsilyl esters and glass columns packed with 10% DEGS. I n order t o render saturated fatty acids ultraviolet absorbing (281 nm), a n analytical scheme was described (60) in which esters were formed by reaction with p-hydroxyphenacyl bromide. Boekenoogen (9) has edited a book comprehensively reviewing recent methods for the analysis of fats and oils. There are sections on mass spectroscopy and on paper, thin-layer, and gas chromatography. Vegetable oil mixtures were analyzed (61) by ester formation and gas chromatographic separation, with the emphasis on varying ratios of blended oils, followed by determination of composition. The application of paper chromatography to the indentification and semi-quantitative analysis of varnish oils was explained (86) which used iodine vapor for detection and photometric methods for semi-quantitative estimates. Gasliquid chromatography with silicone grease columns and programmed temperature was used (39) t o separate methylated dimer acids from the methyl esters of CI8fatty acids. T h e fractionation of coconut oil triglycerides by gas-liquid chromatography was described (12) and Lauro (65) determined fish oil in vegetable oils by modifying the octabromides test and claimed sensitivity t o 1% for fish oil in soya oil. Unusual resin acids in tall oil wtre isolated and identified (126) using silver nitrate columns, gel permeation, and gas-liquid chromatography. A rapid method for measuring the iodine value of vegetable oils was compared (80) t o three other methods for precision and reproducibility. Mordret (76) reviewed and compared methods used for determining t h e unsaponifiable content of oils and also described the use of liquid-liquid extractors for the purpose. A collaborative examination was described (76) for determining linseed oil foots by the phosphoric acid test. Over 800 samples of linseed oil were used in this work. ASSOCIATED MATERIALS
Anderson ( 2 ) has supplied Kovats' retention indices for 75 solvents on
three different columns and shown relative response factors for different detectors. Unexplained are some deviations in response factors with thermal conductivity detectors from those published elsewhere in t h e literature, particularly for some alcohols and ketones. Stuckey (100) used a 300 foot stainless steel capillary column coated with 1,2,3tris-2-cyanoethoxy propane to separate saturated hydrocarbons from aromatic hydrocarbons b y gas chromatography. An oxidation reaction followed by potentiometric titration of the corresponding acids formed was described (62) for differentiating isomers of xylene and toluene. Gas chromatography was used (11) to examine turpentines obtained from different sources, and the authors were able to distinguish the geographical origin of some of the samples. Gruenfeld (36) published a procedure for quantitatively determining toxic solvents such as aromatic hydrocarbons, chlorinated hydrocarbons, and alcohols in a variety of products, by use of NhIR spectroscopy. T h e results were compared to analyses made by gas-liquid chromatography. A report was issued (29) describing the gas chromatographic analysis of lacquer solvents containing naphtha diluent. Separation was made possible by a highly selective fractionating column that rejects saturated hydrocarbons, allowing measure of the principal solvents. A procedure was published (85) for determining alcohols like isopropanol and butanol in water miscible enamels, by a combination of steam distillation and gas chromatography. The separation of petroleum distillates by steam distillation from paints, varnishes, and other materials was outlined (36). Jeffs (50) explained his technique for measuring moisture in powdered polymer products by gas chromatography. A study was made (115) of solvent retention by vinyl resins, by dissolving the films in high-boiling solvents and determining the residual solvent. Schweppe (92) applied published methods to the separation and identification of organic pigments in paint, and described his application. The structure of some organic pigments was studied (73) b y spectroscopy including infrared, NMR, and mass spectrometric data. Valero (109) reviewed the analysis of organic pigments, referring to many different techniques. Kruh (64) outlined a method for solubilizing copper phthalocyanine pigment and analyzing by the use of EDTA. A rapid complexometric procedure for determining the total zinc in lithopone was published (111). The complexometric determination of zinc in zinc oxide, chromate, and sulfide pigments was explained (55) for samples containing alkaline earth carbonates and
copper phthalocyanine and procedures were also included for measuring other such ingredients. To determine watersoluble substances in inorganic pigments such as zinc and chrome yellows, basic and tribasic lead sulfate, a conductimetric determination was developed (5)* Atomic absorption spectrometry was used (90) to determine zinc in electrodeposited films. A complexometric method was published (112) for analyzing single-metal paint driers for lead, zinc, calcium, cobalt, and manganese. Rossel (89) presented a n analytical procedure for determining t h e lead content of vehicles from oil-based red lead paint's. H e claimed the investigation showed connections between rheological behavior and the lead content of the vehicle. A n atomic absorption spectrophotometric method for determining calcium in paint driers was published by Foss and Houston ($2). Haase (37) described his method of treating coatings to remove the plasticizers and his application of gas chromatography and thin layer chromatography t o the identification. A study was made (91) of the separation of polymeric plasticizers by gel-permeation chromatography. Gas-liquid chromat'ography was applied (21) to the analysis of light products as impurities in diethylhexyl phthalate. ,4 paper was published (66) with procedures for measuring esters of phthalic acid colorimetrically using the hydroxamate method and a thin layer chromatographic method for separating other carboxylic esters used as plasticizers. Majors (72) applied high-efficiency chromatography to the separation and the determination of some industrially important antioxidants and plasticizers and investigat'ed the use of controlled porosity support materials, with and wit'hout liquid phase. Wheeler (117) critically reviewed, with 132 references, methods t o identify and determine most of the currently available antioxidants in polymeric materials. Konig (58) used gas chromatography to separate, identify, and measure the solvents and the propellants used in spray containers for coatings. Both spectrographic and colorimetric methods were presented (17) for determining microgram amounts of bis(tri-n-butyl tin) oxide in aqueous solution for use in the laboratory evaluat'ion of antifouling paints. Hoffman (44) determined barium metaborate volumetrically in paint after extraction, applying the method to alkyd and oil-based paints as well as latex films. Reutner (88) applied thin-layer chromatography to the analysis of waxes and wax mixtures, obtaining characteristic chromatograms for different products. Meddle and Wood (74) developed a
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procedure for determining toluene diisocyanate in air without interference from aromatic amines b y drawing the air through two different solutions, developing color complexes, and basing the calculation on the different optical densities. Eider (66) analyzed naphthenic acids from various sources for their composition by using gas chromatography, tentatively identifying 16 of the components, and described plans to further investigate with infrared and mass spectrometry. Flame emission spectrophotometry was used (27) to determine the phosphoric acid content of the acid component of etch primer paint. Results were compared to titrimetric methods. LITERATURE CITED
(1) Alexander, L. E., “X-ray Diffraction
Methods in Polymer Science,” WileyInterscience. Sew York. 1969. (2) Anderson,‘D. G., J Paint Technol., 40, 549 (1968). (3) Anderson, U. G., Tessari, D. J., ibid., 42, 119 (1970). (4) Audebert., R.., Ann. Chim.. 3. 49 (1958). ,
I
(7) Bezuglyi, g. I)..’ Poiomarev. Y . P..’ Zhur. Anal. Khim:, 23, 599 (1958). (8) Blazejewica, L., Z. Anal. Chem., 234, 121 (1968). (9) Boekenoogen, H. A., “Analysis and Characterization of Oils, Fats, and Fat Products,” Vol. 2, Wiley-Interscience, Sew Y0.k 1 Q f i R (10) Boni. K. A.. Sliemers. F. A , . “Internationai Sympbsium on ’Polymer Characterization,” Interscience, New York, 1969. (11) Brus, G., Bentejac, It:, Prevot, F., Ann. Fals. Expert. Cham., 61, 233 (1968). (12) Bugaut, &I., Bezard, J., J . Chromatogr. Sci., 8, 380 (1970). (13) Carrega, hf., Bonnebat, C., Zednik, G.. ANAL.CHEM.,42, 1807 (1970). (14) ’Chakrabarty, 11.RI., Bhattacharrya, D., Kundu, M. K., Analyst, 95, 85 (1970). (15) Chicago SOC. Paint Technol., “Infrared Spectroscopy: Its Use in the Coatings Industry,” Fed. SOC. Paint Technol.. Philadebhia. 1969. (16) Chicago SOC. -PaiIit Technol., J . Paint Techno/.,41, 608 (1969). (17) Chromy, L., hllodzianowska, W., Uhacz, K., Warchol, It., J . Oil Colour Chem. Ass., 63, 121 (1970). (18) Cianetti, E,, di Cerbo, 11.,Salvi, A,, Pitture Bern., 44, 2 (1968). (19) Cook, W. S., Jones, C. O., Altenau, A. G., Can. Spcctrosc., 13, 64 (1968). (20) de la Court, F. H., Farbe Lack 75, 218 (1969). (21) Courtier, J. C., Pilot, E., J . GasChromatogr. Sci., 7, 378 (1969). (221 David. 11. J.. Stalev. H. B.. “Analvtical Chemistry ’of the‘ Polytkethanes,” Wiley-Interscience, New York, 1969. (23) Donike, R l . , Hollmann, W., Stratm m n . I).* J . Chromatour..43.490 (1969). (24) Duebler, K. H., Hagen; E., Plastc Kauf., 16, 169 (1969). (25) Eider. N. G.. J . Paint Technol.., 42., 504 (1970). A*%,
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(26) Elliot, A., “Infrared Spectra and Structure of Organic Long Chain Polymers,” Arnold Ltd., London, 1969. (27) Elliott, W. N., Mostyn, R. A,, J . Oil Colour Chem. Ass., 53, 989 (1970). (28) Esposito, G. G., U.S. Dept. Commerce, Of. Tech. Sew., Rept. No. AD-7 12-312 (1970). (29) Ibid., S o . AD-699-324 (1970). (30) Esposito, G. G., Swann, M. H., ANAL. CHEM.,41, 1118 (1969). (31) Flick, E. W., “Adhesive and Coating Testing,” Padric, S.J., 1969. (32) FOSS,R. A., Houston, D. M,, At. Absorption hrews!ett., 8, 82 (1969). (33) Gedemer, T. J., Plast. Des. Process., 9, 33 (1969). (34) Giammarise, A,, Anal. Lett., 2, 117 (1969). (35) Gruenfeld, hf., J . Paint Techno/.,42, 237 (1970). (36) Grunefeld, M., Ratay, A. F., itid., p 498. (37) Haase, H., Kaut. Gummi Kunstst., 20,501 (1967); 21, 9 (1968). (38) Hagen, E., PZuste Kaut., 15, 711 (1968). (39) Hase, A,, Harua, O., Autio, RI., Acta Chem. Fenn., 42, 266 (1969). (40) Helm, R. V., ANAL. CHEM.,41, 1342 (1969). (41) Herb, S. F., Martin, V. G., J . Amer. Oil Chem. SOC.,47, 415 (1970). (42) Hillman, D. E., Wells, H., J . Oil Colour Chem. Ass., 52, 727 (1969). (43) Hippe, Z., Stareczek, T., Chem. Anal. (Warsaw),14,725 (1969). (44) Hoffman, E., 2. Anal. Chcm., 234,354 (1968). (45) Holsworth, R. hl., J . Paint Technol. 41, 167 (1969). (46) Hummel, D. O., Farbe Lack, 74, 11 (1968). (47) Hummel, D. O., “Infrared Analysis of Polymers, Resins and Additives,” Interscience, New York, 1969. (48) Irako, K., Anzai, S., Onishi, A., Bull. Chem. SOC.Japan, 41,501 (1968). (49) Jacin, H., Slanski, J. $I,, ANAL.CHEM., 42, 801 (1970). (50) Jeffs, A. R., Analyst, 94, 249 (1969). (51) Jernejcic, hl., Premru, L., JOCCA, 52, 623 (1969). (52) Kaczaj, J., Trickey, I?.,ANAL.CHEM., 41, 1511 (1969). (53) Katnik, It. J., J . Chromatogr. Sci., 8, 361 (1970). (54) Kellum, G. E., Uglum, K. L., ANAL. CHEM.,39, 1623 (1967). (5.5) Khalifa, H., Abdallah, A. M., Microchem. J., 14, 399 (1969). (56) Khranovskii, V. A,, Sin. Fiz.-Khim. Polyuretanov, p. 174 (1967). (57) Knappe, E., Farbe Lack,75,36(1969). (58) Konig, H., 2. Anal. Chem., 232, 427 (1967). (59) Kornbau, S. D., Ziegler, D. C., ANAL.CHEM.,42, 1290 (1970). (60) Kosuge, S., Furuta, 11.,Yamaguchi, O., Jap. Anal., 17, 310 (1968). (61) Kraus, A.,, Lange, A , , “Introduction to the Chemical Analysis of Plastics,” Iliffe, London, 1969. (62) Kreshkov, A. P., Guretskii, I. Y., Smolova, N. T., ltyaguzov, A. I., Lakokrasoch. Muter. Ikh Primen. (2), 53 (1970). (63) Kropivnitskaya, R. A., Pogosyan, E. T., Armyan. Khim. Zh., 21, 119 ( 1968). (64) Kruh, D., ANAL. CHEM.,42, 1849 (1970). (65) Lauro, hl. F., J . Amcr. Oil Chem. SOC.,47, 234 (1970). (66) Lehmann. G.. Wilhelm., G.., 2. Anal. Chem., 238, 415’(1968). ~
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(67) Leuteritz, F., Brunner, G., Plaste Kaut., 14, 887 (1967). (68) Low, M. J. D., Mark, H., Appl. Polym. Symp. (lo), 145 (1969). (69) Low, M. J. D., Mark, H., J . Paint Technol., 42, 265 (1970). (70) McGinness, J. D., Scott, R. W., Mortenson, J. S., ANAL.CHEM.,41, 1858 (1969). (71) McGowan, R. J., ibid., p 2074 with correction 42. 942 (1970). (72) Majors, R., J . ‘Chromatogr. Sci., 8, 338 (1970): (73) Manukian, B. K., Lichti, H., Chimia, 24, 1 (1970). (74) Meddle, D. W., Wood, R., Analyst, 95, 402 (1970). (75) von Mikusch, J. D., J . Paint Technol., 41, 472 (1969). (76) Mordret, F., Rev. Franc. Corps Gras, 15, 389 (1968). (77) Mori, S., Furusawa, M., Takeuchi, T.. ANAL.CHEM..42. 959 (1970). (78) ’Morita, Y., Kogbre, Y., J : Chem. SOC.Japan, Pure Chem. Sect., 88, 1179 (1967). (79) Myers, R. R., Long, J. S., Treatise on Coatings, Vol. 2., “Characterization of Coatings; Physical Techniques,” Dekker, Sew York, 1970. (80) Sededceva, L., Mashlozhir. Prom., 4, 27 (1968). (81) Norton, E. J., Turner, L., Salmon, D. G., Analyst, 95, 80 (1970). (82) Paint Manuf., 39 (4), 32 (1969). (83) Petov, G. AI., Shkurko, V. N., Lakokrasoch, Mater. Ikh Primen. (3), 37 (1969). (84) Post, M. A., J . Paint Techno/., 41, 567 (1969). (85) Poy, F., Grazioli, G., Znd. Vernice, 22, 7 (1968). (86) Prazak, I., Chcm. Prum., 18, 487 11968).
(87) Quinn, E. J., Osterhoudt, H. W., Heckles, J. S., Ziegler, D. C., ANAL. CHEM.,40, 547 (1968). (88) Reutner, F., Fette, Seifen, Anstrichm., 70, 162 (1968). (89) Rossel. T., FarbeLack, 76,562 (1970). (90) Sato, T.,’Motoyama; Y., Ohe, O., J . Paint Technol., 41, 438 (1969). (91) Schroder, E., Mische, W., Plaste Kaut., 15, 258 (1968). (92) Schweppe, H., Ind. Vernicc, 22, 1 (1968).
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(93) Scism, A. J., Anal. Chem. Acta, 42, 177 (1968). (94) Scott, R. W., J . Paint Technol., 41, 422 (1969). (95) Sherwood, A. E., Insulation, 15, 45 (1969). (96) Shlionskaya, 11.A., Nogteva, K. G., Zh. Anal. Khim., 23, 640 (1968). (97) Sonntag, F., Fette, Seifen, Anstrichm., 70, 256 (1968). (98) Stanley, J. B., hloseley, P. B., J . Amer. Oil Chem. SOC.,46,241 (1969). (99) Stevens, M. P., “Characterization and Analysis,pf Polymers by Gas Chromatography, Marcel Dekker, Sew York, 1969. (100) Stuckey, C. L., J . Chromatogr. Sci., 7, 177 (1969). (101) Swann, RI. H., in “Analytical Chemistry of Nitrogen and its Compounds,” Part 2, P. R. Averell & C. A. Streuli, Ed., Wiley, New York, 1970, p 705. (102) Swann, 31. H., Adams, h4. L., Esposito, G. G., ANAL.CHEM.,41, 35R (1969). (103) Swann, RI. H., Cross, C. W., J . Paint Techno!.. 41. 335 (1969). (104) Swinehart; J.‘S., Hannah, It. W., Perkins, W. D., Paint Technol., 33, 75 (1969).
(105) Tanikawa, I., Maniwa, M., Hotta, H., Kobayashi, S., Shikizai Kyokaishi, 42. 349 (1969). (106) Truscott,‘E. D., ANAL. CHEM.,42, 1657 (1970). (107) Tsuge, M., Tanaka, T., Tanaka, S., Jap. Anal., 18, 47 (1969). (108) Ulbrich. V., Plaste Kaut.,, 15.. 546 ’
(1968).
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’
(109) Valero, F., Double Liaison, 165, 55 (1969). (110) Zbid., 167, 369; 169, 457 (1969). (111) Veldwijk, G., Verfkroniek, 40, 427 (1967). (112) Ibid., 41, 362 (1968).
(113) Vinson, J. A., ANAL. CHEM.,41, 1661 (1969). (114) Volodina, V. I., Tarasov, A. I., Kurbatov. D. I.. Zh. Anal. Khim.., 22., 1438 (1967). ’ (115) Weigel, J. E., Sabino, G., J . Paint Technol., 41, 81 (1969). (116) Wetters, J. H., Smith, R. C., ANAL. CHEM.,41, 379 (1969). (117) Wheeler, D. A., Talanta, 15, 1315 (1968). (118) Wiesner, I., Colollect., Czech. Chem. Commun., 32, 4216 (1967). (119) Willerns, J. J. H., Verfkroniek, 42, 53 (1969).
(120) Withers, M. K., Aust. Paint J., 1 4 , 9 (1969). (121) Wolff, J. P., “Textbook of Analysis of Fats,” Aeoulay, Paris. (122) Yeaele. M. L.. J . Paint Technol.., 42., 472 (197%).’ (123) Zelenina, E. N., Zavodsk. Lab., 34, 1440 (1968). (124) Zimmerli, F. H., J . Paint Technol., 40, 26 (1968). (125) Zinkel, D. F., Rowe, J. W., Zank, L. C.. J . Amer. Oil Chem. Soc.., 46.. 633 (i969). (126) van Zuylen, J., J . Oil Colour Chem. Ass., 52, 861 (1969).
Essential Oils and Related Products Ernest Guenther, Gilbert Gilbertson, and Roman T. Koenig, Fritzsche Dodge & Olcott Inc., New York, N . Y.
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HIS THIRTEENTH REVIEW of the analysis of essential oils and related products covers the literature from September 1968 to August 1970, inclusive. I t follows the general pattern previously established (230). The volume of analytical investigations published during this time has again made it impossible to include all papers. We have attempted to consider most contributions dealing directly with the investigation of essential oils, but in related fields, such as the analysis of volatile flavor components or the structural elucidation of minor constituents, it was necessary to select only a limited number of papers to indicate the analytical progress in these areas. Gas chromatography continues to be the basic method employed in the analysis of essential oils, but it is most often used in conjunction with other instrumental or physicochemical techniques. The direct coupling of a gas chromatograph with other instruments, such as a mass spectrograph, has become common in well equipped laboratories. The immense quantities of data obtained by these techniques has become burdensome to process, retrieve, and utilize effectively. For this reason, some laboratories have applied computer calculations and comparisons to the output of various instruments, and have thus greatly increased the speed of analysis and the usefulness of the data obtained. It is expected that this trend toward computerized analysis will accelerate. Official Compendia. The eighteenth revision of the United States Pharmacopeia (681) became official on September 1, 1970. Peppermint water is no longer included in this compendia, while specifications for thymol were added. The thirteenth edition of the National Formulary (468) also became official on the same date. Specifications for oil cardamom, oil rosemary, oil
thyme, oil pine, eucalyptol, and thymol were dropped from the new edition while standards for peppermint water and triacetin were added. A0 of January 1970 the Essential Oil Association of the U.S.A. (189) issued 7 new specifications; 279, phenyl ethyl phenylacetate; 280, geranyl phenylacetate; 281, aldehyde C-7; 282, iso-pulegol; 283, citronellyl propionate; 284, methyl hexyl ketone; and 285, methyl diphenyl ether. A gas chromatographic procedure for citral dimethyl acetal was added as part of Specification No. 273. Revisions were issued for Specifications No. 126, oil Abies alba; 36-A, oil cedarwood Texas; 36-B, oil cedarwood Virginia; 9, terpiny1 acetate; 26, aldehyde C-10; 79, aldehyde C-14; 127, cedryl acetate; 151, para-methoxy acetophenone; 152, vetiver acetate; 162, geranyl formate; 169, benzodihydropyrone; 187, ethyl formate; 206, citronellyl formate; 257, methyl ionone; and 17, citronellol. Books and Articles. Among a number of books and many articles of general interest to the essential oil analyst, a few would appear to be particularly pertinent. “Perfume and Flavor Chemicals,” a two-volume work by Arctander (88) appeared in 1969. Bedoukian (68, 63) contributed two more of his well known articles on progress in perfumery materials. A review of terpenes and terpenoids by Booth and Autenrieth (84) appeared in the Kirk-Othmer Encyclopedia. Burger (93) wrote the third edition of “Die Natuerlichen and Kuenstlichen Aromen,” and Appell (26) brought forth his ninth article on the physical foundations in perfumery, this one dealing with odorimetric methods. General Procedures. Computerized instrumental analysis was applied both to control and basic research. Winski and Rube1 (781) gained better accuracy and precision and faster
information feedback for better process control both in production and research by using computer systems in gas chromatography. By similar means, McDaniel (428) was able to perform the calculations for multivariate statistical analyses, making it possible to control three or more chromatographic patterns and to distinguish clean oils from weedy oils or to differentiate oils of various geographic origin. Sasaki et al. (693) obtained printed structural formulae of organic compounds by applying a computer to the outputs from mass and N M R spectrometers, and I R and UV spectrophotometers. The data were then correlated by the computer which was programmed to analyze them and determine the chemical structure. Scott (606) reviewed some of the newer analytical methods including zone refining, head space analysis, gas chromatography, identification by mass spectrometry together with enrichment techniques, I R spectrometry with interrupted elution chromatography, and N M R spectrometry with sensitivity enhancement. High resolution techniques, various columns, sample manipulations, and detection procedures used in aroma research were reviewed bv Teranishi (660, 661). The use of wide diameter (0.5 inch) packed columns, large open tubular columns, and a 0.001-inch methyl silicone membrane for the enrichment of the compound in a peak while passing it into a mass spectrometer were developed by Karasek (342). The gas chromatographic analysis of various essential oils was significantly speeded up without adversely affecting resolution by MacLeod (429) by applying programmed pressure as well as programmed temperature. The odors emanating from perfumed soap were studied by Sfiras and Demeilliers (608), and Gaspar (205) proposed
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