Coatings M . H.
Swann,
M. I. Adorns,
and G.
G. Esposito
Aberdeen Proving Ground, Md.
T
HIS mExx1.u REVIER- represents the
authors’ choice of the important contributions in coating analysis that 1iai.e been found since October 19.58. I t is hoped that, in an attempt to be sdcctive, valuable publications have not been omitted. Other reviews of a similar nature have appraretl in this period (85-88),in addition to some on special subjects. Herrlinger (/tSi has reviewed analytical work done on tall oil products including the histor:+-of the dewlopment of some of the procm%res and the n-ork of the American Society for Testing 1Iatcrials in this field. I lie analysis of organosilicon compounds as reviexed by Smith (106), with special reference to the silanes and siloxanes. l l i i s review includes silicone fluid>, rcsins. rubbers, greases, and emulsions, and covers elemental anal?;sis, tieterniination of side groups, the annlysis of polymers and chlorosilanes, and the (letemination of silicones on fabrics. .Inother review with 58 refcrences cleuls with the use of infrared, near infrarrtl, ultraviolet; Raman, emission, mass, and nuclear magnetic resonance ( S l l R ) spectroscopy :or the identification of organosilicon monomers and polxmers (105). Tn.0 outstanding books have also appcnred in this review period. Kline (65) has edited 20 chapters in Part 1 of “Anal>-tiral Chemistry of Polymers” that are concerned with the determination of impurities in monomers, characterization of the chemical composition and pli~-sicalpropvrties of polymers, antl identification and analysis of many coating materials, wit’h procedural details in rases of previously unpublished tcsts. Another book titled “Chemical Analysis of Resin-Based Coating Materials” (62) contains three sections, inrluding the analysis of oilh s c d cmcting materials, laequcrs, and a group of selected subjects concerning the application of instrumental trchnirjucs nn(l chcmicd anulFsis for specific constituents. , 7
GENERAL ANALYTICAL
SCHEMES
-4study of the feasibility of applying mass spectronietry to the analysis of paint vehicles has been reported (56). Dannenberg arid associates (ID) ex-
plain the principle of analyzing qualitative]? and semiquantitatively, clear surface coatings of 0.1- to 0.5-mil thickness by infrared spectroscopy in reflected light. The analysis of simple alkyd resins by aminolysis using monoethanolamine is described in detail by Schrorier and Thinius (98) and includes information on their technique for identifying various dicarboxylic acids, fatty acids, and polyols. Schroder (97) has also contributed a brief treatment of the application of ion exchange resins to the identification of cellulose esters, polyvinyl esters, and various types of polyamides. Two papers on the analysis of water emulsion paints have appeared in this review period. Hanson (45)has treat,cd the subject extensively, giving examples of procedures used for diffcrent types of products t’o separate pigment, and to identify and determine constituents of the solvent, oils, plusticizers, wetting agents, polymeric components, and pigment. A different approach (110) to the analysis of emulsion paints utilizes specified solvents for digestion of films dried in a special mannc’r and involves depolymerization of the butadienestyrene copolymers. Rates and products of tliermal degradat’ion of polymers a t tenzperatures up to 850” C. and at various pressures were studic.d in connection xvith a number of polymers by Madorsky and St’raus ( 7 7 ) . T,ehrlP a n d Robb (74) studied the process hy n-liich polymers degradate by directlj exbmining degradation products with gas chromatography. They coated 9, filament nith the polymer sample, heated it quickly to the desired temperature, and generated the degradation products directly into the chromatographic apparatus. Their study incliuded poly(viny1 ~ h l o r i d ~ - acetate), polystyrene, poly(viny1 acetate), and poly(methg-1 methacrylate). Quantitative nwasure of the per cent acetate in the copolymers \ins nintle. Hobden (56) has also reportcd the application of gas-liquid chromatography to paint and allied industries, supplj-ing qualitative and quantitative methods for t,he analysis of resin solutions and solvent mistures. Most of the analyses were made using a column of Celite 545 coated xvith dinonj-l phthalate or
poly(ethy1ene glj-rol). S i n e dingr:tms and six tables are included in this rcport. In another article (90) on the analysis of polymers by v:rpor phase chromatography, the samples are pyrolyzed a t 550” C. in the nbsencc of oxygen and the characteristic patterns of the chromatographs examined. Included in this investigation arp such 1 ~ 0 1 ~ mers as poly(viny1 acetate), plienoli: and urea resins, poly(methy1 methniyvlate), polyesters, and polyetliylenc.. Langford and T’aughan (72) Iiul:lislieti details for separating mixed pG!yn-iers by tmo-dimensional paper chrom:: tography. By developing with t1v-o different, solvents, they separated poly(viny1 acetate), poly(viny1 hutyral), cc~!iulnse acetate, polystyrene, and poly(i~iny1 chloride). SPECIFIC CLASSES OF HIGH POLYMERS
Hummel (61j has described his schcmme for analyzing terephthalic pol:,eider lacquers. Anderson arid Freeman ( 2 ) applied differentiai thermal anal!-.sis to the characterization of a scrics of saturated polyesters. The thrrmograms obtained were unique for each system. and for comparison betxccn systems they used the cndot bands between 250’ and 430” description of the infrared absorpt,ion bands of solutions of polyestpr rchsins in styrene over the 2- to 15-micron region is presented by Grisenthwaiti? (3). He shows how he ident,ifies fumaric, phthalic, adipic, chlorendiis, csriic, isophthalic, terephthalic, and tctrachlorophthalic acids along v;ith ethanediol, 1,2-propanediol, diethylcne glycol, triallyl cyanurate, methyl methacrylate, and trichloroethyl phofphate. Paper chromatography has also b e e n employed in the analysis of pol~.l~sfc~rcE by Arendt and Sclicnck (Jj, v\.lio explain in detail their tc,chnique for recoieriiig and chromatographing both dicnrbosylic acids antl polyols. The vinyl acetate coiltent of vinyl chloride-acetate eopolynicrs was determined by ’l‘liinius (113) et al., by saponifying in diosanv and isolating the free : i d s with an ion cwhange column. They blien determined total acidity by titration, chloride argentimetrictally, and the acetate hg- difVOL. 33, NO. 5, APRIL 1961
33 R
ference. Langford and Vaughan (71) achieved separation of the mixed polymers poly(viny1 chloride) and poly(viny1 acetate) on a chromatographic column of activated charcoal saturated with methyl isobutyl ketone, the vinyl chloride being the least strongly adsorbed. They stated that Whatman No. 4 paper could also be used with the same solvents, the acetate spot remaining stationary. The application of infrared spectrometry to the qualitative analyses of poly(viny1 chloride) and copolymers with vinyl acetate is outlined by Burley and Bennett (9); its application to the quantitative analysis of plasticized poly(viny1 chloride) systems has been described by Luther, Meyer, and Loew (76). Glass and Melvin (38) investigated the determination of the composition of copolymers of soybean vinyl ether with each of six low-alkyl ethers, using infrared spectra. Mano (78) contributed a new color reaction for distinguishing methacrylates from other acrylates. A few milliliters of concentrated nitric acid are added to the thermally depolymerized resin, followed by water and a limited amount of zinc powder. Methacrylates are identified by the formation of a blue color. A quantitative polarographic method for analyzing a mixture of methacrylic acid and methyl methacrylate has been published (94). Since the latter is not reduced in the first part of the analysis, a polarogram is obtained on derivatives of bromination using 3M bromine in methanol. The application of mass spectrometric analysis to copolymers of methyl methacrylate with styrene and methyl acrylate has been accomplished (111). Tobolsky and associates (114) determine styrene in styrene-methyl methacrylate copolymers from the absorbance of 1mg. samples in 1 ml. of chloroform a t 269 mb, Gas chromatography has been applied to the analysis of acrylate and methacrylate polymers, qualitatively by Radell and Strutz (90) and quantitatively by Strassburger et al. (109). -4variety of publications has appeared concerning the analysis of nitrogen resins. Deeleman and van der Schee (21) studied the effects of time and temperature of heating, and of film thickness, on the determination of the nonvolatile content of urea resins of different degrees of butylation, blended with alkyd resins. They concluded that the nonvolatile varies with the acid and hydroxyl contmt of the alkyd resin. Nitrucellulose in mixtures of cellulose resins was measured by Rosenberger and Shoemaker (92) from the infrared spectra, using the characteristic absorption band a t 11.02 microns. After removal of pigment and solvents, the dried film was weighed and dissolved in acetone, and spectra were obtained from 34 R
ANALYTICAL CHEMISTRY
the solutions. Schroder (96) determines the amine and acid components of polyamides following acid hydrolysis and treatment with ion exchange resins. A spot test has been described (11) for differentiating between polyesterbased urethane polymers, polyetherbased polymers, and simple polyesters. A method of qualitative analysis by infrared spectroscopy was established by Corish (16) for a wide range of polyurethanes. In some cases direct infrared exaniination was made of microtomed sections of the polymer; in other cases, a method of hydrolysis and separation was employed. Copolymers of acrylonitrile n-ith methylvinylpyridine were analyzed by Stafford and Toren (108) ; the methylvinylpyridine by ultraviolet absorption, and the acrylonitrile by titration after acid hydrolysis. Vinylpyridine, acrylonitrile, and acrylic acid units in elastomeric polymers were determined by standard Kjeldahl and nonaqueous titration procedures (8). The analysis of cellulose acetatebutyrate has been accomplished through a combination of saponification and the use of an ion exchange resin column (99).
Phenol-formaldehyde condensates were analyzed by sulfonation and elution of the resultant phenolsulfonic acids from chromatographic columns, followed by measurement of the absorbance of the resulting solutions at 274 and 280 mp (73). By working with the methyl esters, a number of resin acids have been differentiated by Genge (57) using the mass spectrometer, and quantitatively measured by Hudy (69) using hightemperature gas chromatography. A method for depolymerizing crude cyclopentadiene products was described and the results of gas chromatographic analysis discussed (18). In a recent publication, Esposito (16) supplied details of his method for detecting chlorosulfonated polyethylene, and for measuring the sulfur and chlorine following a single fusion. Quantitative determination of the composition of the copolymer of tetrafluoroethylene with trifluoroethylene by infrared spectroscopy was achieved (112) using a lithium fluoride prism. Beitchman ( 7 ) reported and discussed correlation between the infrared spectra of 28 samples of roofing asphalt and durability of the coatings. Both carbonyl and hydroxyl absorption are related to durability and to changes at the wave lengths of 2.91, 5.88, 8.66, and 9.71 microns. Seifert (102) tabulated the colors obserwd in transmitted and in reflected !ight of films of nitrocellulose, phenolic resins, poly(viny1 acetate), casein, glutin, and starch, when treated with each of five reagents. Rapid
methods of identifying resins through the detection of formaldehyde, phenols, melamine, and styrene are described by Feigl and Anger (29). Also included are the detection of epoxy resins and a method for distinguishing betn-een chlorinated rubber and neoprene. SPECIFIC CONSTITUENTS
A recent contribution (27) measures the dicarboxylic acid volumetrically in modified alkyd resins containing a single acid and gives a detailed procedure for application to those resins containing the isophthalic isomer. Secrest and Kosciesza (100) determined the plert-butylbenzoic acid content of alkyd resins with a spectrometric procedure based on the difference in absorbance a t 282.5 and 300 nib, The accuracy attained varied Kith the degree of unsaturation and osidation of the separated fatty acids. Adipic acid has been measured volumetrically in alkyd resins modified with drying oils by Grimmer (42). Paper chromatographic analysis has been applied to the dicarboxylic acids in polyesters (53). The polyesters in acetone are saponified with aqueous alkali, neutralized, and passed through a cation exchange column. The acids are recovered and chromatographed on paper with benzene-acetone-formic acid-u-ater ( 5 :5 : 1:3) as developer, Golosova (40) separated phthalic acid isomers by ascending paper chromatography with propyl alcohol-ammonia-water. Hall and %ICNutt (44) applied the polarographic technique to the determination of terephthalic acid in mixtures of phthalic acid isomers, but did not describe its application to resins. A detailed procedure has been supplied for determining chlorendic acid in fire-retardant paints ($8). The chlorendic acid is isolated as the dipotassium salt by saponification of the paint vehicle in isopropyl alcohol, extracted with solvent from the acidified saponification residue, and analyzed by titration in a nonaqueous medium. The infrared spectrum of a typical chlorendic acid alkyd and a brief discussion of its characteristics are included in this paper. The degree of unsaturation in unsaturated polyesters was measured volumetrically using bromine chloride followed by t'hiosulfate titration (12). Chiang and Bobalek (13) describe the calculation of cis-trans ratio in unsaturated polyester resins from the absorbance meamrements a t 724 and 967 cm.-I of the infrared spectrum of prepared films. The hydroxyl numbers of some polyesters and poiyethcrs were determined by Hilton (65'1 from the near infrared absorption iri the 2.0to 3.2-micron region. Using separate titrations with aqueous alkali and sodium methylate, Huhn and Jenckel
(60) were able to measure from 10 to
90% maleic anhydride in maleic acid and applied their method to styrenemaleic anhydride-maleic acid copolymers. Silas and associates (108) made use of empirical functions of the area between 12.0 and 15.75 microns to measure cis-1,4 additions from the infrared spectra of polybutadienes. They measured trans-1,4 and vinyl-l,2 additions a t 10.3 and 11.0 microns, respectively. The polarographic determination of styrene monomer in polyester resins, free of interference from phthalates, fumarates, or maleates, is described by Ayres and Whitnack (6). Details of a procedure for the partial separation, nitration, and resulting spectrophotometric determination of bound styrene in raw and cured polymers were published ( 5 0 ) . A three-wave length ultraviolet measurement was used as a check for any unexpected interference and the average accuracy was of the order of 0.2% of the styrene content. Essentially the same material and its application to bound styrene analysis in styrene-butadiene copolymers appears in another journal (51). Durbetaki (24) has contributed two methods for determining oxirane oxygen in salts of epoxy acids and resins, and in the presence of amines. The salt of the epoyy acid is decomposed in acetic acid to the epoxy acid and the metal or aniiiii. acetate, and the acid is titrated nith hydrogen bromide or perchloric acid, with visual indicators. Terminal epoxides and olefins may be determined simultaneously in the same sample from the absorption bands a t 1.65 and 2.20 microns in the near infrared region. according to Goddu and Delker ( 3 9 ) . Thruugh the use of prepared reference standards, Lady and associates ( 7 0 ) converted absorption inteiisitirs of infrarrd hands arising from methyl and p ssilicone polymers into phcnyl g ~ ~ u in actual molar ratios of the two constituents. Shull (10.5) estimates freeand hydrogrn-bondcd liydrosyl, methyl, and phenyl content of dimethyldiphenylsilicone resins from the absorbance ratios in the 2- to 4-micron region of their infrared spectra. The application of XMR spectroscopy to the determination of methyl and phenyl groups in niethylphenylsilosane polymers has been reported ( 6 7 ) , in which dioxane was used as solvent and as internal standard. S o l l , Damm, and ICrause (32) outline a chcniical method for niensuring silanol groups in silicone resins. They dissolve tjhe resin in chlorobenzene or diosnne, reflux with isocyanatohenzene, and react the excess with isobutylamine. The residual amine is then titrated with hydrochloric acid. This determines the hydroxyl preseiit ns water and in silanol groups,
then Karl Fischer reagent is used to make the correction. A colorimetric technique for the microdetermination of nitrogen in cellulose nitrates was contributed by using phenolGardon and Leopold (M), disulfonic acid. A rapid method for determining nitrogen, for use in control of the manufacture of nitrocellulose (56), consists of saponification, reduction of nitrates to ammonia, and titration in a special illustrated apparatus. Hydrogen peroxide and Devarda's alloy are used and both micro and macro techniques are described. Still another scheme for measuring nitrogen in nitrocellulose (81) separates the nitric oxide produced by the action of ferrous sulfate in acid (using a current of argon), converts it into nitric acid with peroxide and oxygen, and titrates the acid formed. Residual acrylonitrile monomer in styrene-acrylonitrile polymers is determined polarographically (14) a ithout using combustive or separative techniques, and without interference from styrene monomer. A procedure for measuring polyamide end groups is claimed (115) in which the resin is heated to 135' to 150' C. in a stream of nitrogen, rapidly cooled, dissolved in propyl alcohol, and titrated to a phenolphthalein end point. An adaptation of the colorinirtric determination of urea with Ehrlich's reagent to the analysis of urea-formaldehyde resins was made (1) which can be used in the presence of melamine-formaldehyde resins. A plan for estimating the degree of condensation of ureaformaldehyde resins (69) is based on measure of the total amount of formaldehyde obtained by decomposing the sample with 40% phosphoric acid and steam distilling the liberated formaldehyde. The polarographic determination of but) 1 methacrylate in plasticized poly(butyl methacrylate) (23) is based on the observation that the single wave given by butyl methacrylate in a 0.025 tetraniethj-1 ammonium iodide solution in 94% methanol containing 6% benzene is superimposed on the second of two naves given by dibutyl phthalate, but from the polarogram, the contents of each ester can be determined. Spagnola (107) reviews various methods for determining rosin in coating materials, and reports on the activities of ASTM Committee D-1 (Subconimittee IX. group 7 ) in the cooperative development of a test procedure for rosin in protective coating vehicles. The addition of glycol lias been used ( 2 2 ) to reduce the time required to extract free phenol from phenol-for. maldehyde resins by steam distillation. Feigl and Jungreis (30) have suggested a more direct spot test paper of the well-kno\i n Gibbs indophenol test as
applied to resin classification. A filter paper treated with a saturated benzene solution of the reagent is exposed to the pyrolysis vapors, then exposed to ammonia fumes. The characteristic blue color forms with all materials of a phenolic nature as well as aromatic compounds containing oxygen in open or cyclic side chains. A study of this modification with an assortment of resins shows no real differentiation between epoxy resins, phenolic resins in general, p-phenylphenol-formaldehyde, terephthalic polyesters, etc., but it is considered useful as a general classification test in routine identification of resins and plastics by chemical means. The analysis of fluorocarbon plastics for chlorine and fluorine content (64) is accomplished volumetrically by slowly fusing the sample with potassium carbonate a t 500' C., dissolving in water, titrating a portion by the Volhard method, then passing another portion through a column of Amberlite IR-122 into dilute alkali and titrating with thorium nitrate. Haslam, Hamilton, and Squirrel (47) and also Fertig (32) have applied the oxygen flask combustion method to the determination of chlorine in polymers and plasticizers. OILS AND FATTY ACIDS
A book has appeared in this review period on the subject of analysis of fats and oils (80) containing accepted laboratory procedures that are commonly employed. Link ( 7 5 ) has presented a paper reviewing the general methods of analysis for drying oils. Chemical, physical, instrumental, and special methods of test are given, including ultraviolet and infrared spectrophotometry, and applications of gas chromatography, n i t h chromatograms of the methyl esters of fatty acids obtained from safflower, linseed, soya. nrid castor oil. Applications of gas-liquid chromatography in this field are appeariiig in increasing number. Craig and LIurty have published their investigations into the separation of saturated from unsaturated fatty esters (16) und the fatty acid composition of a nunibcr of vegetable oils ( 1 7 ) . The effectiveness of different polyesters to resolve mixed fatty methyl esters has been studied and tabulated (84) and the e\perimental conditions outlined. The gas c,hromatographic separation of the rneth3 1 esters of palmitic, stearic, oleic, iinolcic, and linolenic acids on loner molecular m eight poly(ving.1 acetate) colunins was described by Hornstein, Elliott, and Crowe ( 5 8 ) . Kaufnianii and l l a k u s (63) made a comprehensive survey of the applications of reverse-phase partition chromatography for the separation of fatty acid mixtures and describe a two-dimensional VOL. 33, NO. 5 , APRIL 1961
35 R
method involving hydrogenation of unsaturated acids directly on the paper. They were able to separate lauric, linoleic. myristic, oleic, palmitic, and stearic acids. Fenton and Crisler (31) applied nearinfrared spectroscopy to the determination of cis-unsaturation in oils and found that the areas under the absorption bands a t 2.143 microns for cis-polyenes were integral multiples of the areas under the bands for cis-nionoenes. The cis content of oils containing less than 10% trans-triglycerides could be determined accurately using base line measurement, but n hen the per cent transunsaturation was over lo%, changes in the slope of the base line necessitated the use of a calibration curve obtained from a point a t 2.157 microns and peak absorbance measurements. -4 similar study and observation were made by Holman et al. (57). Rhodes (91) has shoitn that by treatment with ferric chloride and mercuric acetate in glacial acetic and sulfuric acids, such acids as oleic, linoleic, and linolenic can be determined colorimetrically in fats and oils. Paquot (89) has made a study of the saponification values of glycerides and discovered that the value varies n i t h alkali strength and boiling point of the alcohol used in the analysiq. The use of 3 5 ethanolic potassium hydroxide or 0.5-V alkali in higher boiling alcohols gave higher values and the recovered fatty acids exhibited lower iodine values and increased conjugated diene content. Such alterations did not occur with 0.5N ethanolic potassium hydroxide. ASSOCIATED MATERIALS
Several papers have dealt with the application of gas chromatography to the solution of solvent problems. Sadowski and Wagner (95) separated from two to eight components from the volatile portion of typical lacquer formulations. Haslam and Jeffs (48) described their use of both polar and nonpolar columns to estimate qualitatively the composition of solvent mixtures. Emmerling (65) extended his study of solvent problems to include the various additives of the water emulsion paints. In still another report (66) the separation of mixed solvents was reviewed and discussed in a general manner. The simultaneous spectrophotometric determination of mixed methyl ethyl ketone and ethyl acetate in liquid rubber solvent base was devised by Freegarde and Jones ($4). They diluted a very small sample of distillate with cyclohexane and measured the absorbance a t 280 and 220 mp. A variety of techniques have been applied to the determination of the metal content of paint driers. The polarographic technique using benzene-
36 R
e
ANALYTICAL CHEMISTRY
methanol with sodium acetate electrolyte a a s used by Kuta (68) for cobalt, copper, iron, lead, manganese, nickel, and zinc driers. The use of flame photometry is described by Secrest (101) for determining the metal content of calcium, cobalt, lead, and manganese driers. Analysis was made by comparing the emission of the samples in solvent mixture with that of a standard. A volumetric method (79) was published in which powdered oxalic acid mas added to the soap solutions of magnesium, calcium, cobalt, manganese, zinc, copper, or lead, the precipitates were washed with hot alcoholtoluene mixture, dissolved in sulfuric acid, and the excess oxalic acid was titrated n i t h permanganate. A blank titration vas also made. The lead drier could be analyzed gravimetrically from the neight of lead oxalate. Hirn and Lucchesi (54) have extended former investigations to include the analysis for zirconium in driers, volumetrically with EDTA. Norwitz (83) applied a wide assortment of analytical techniques to the analysis of calcium resinate. Two separate papers (3, 12) give details for measuring impurities in commercial bisphenol A by the paper chromatographic technique. Hilton (53) devised a colorimetric estimation and detection for phenolic antioxidants. The antioxidant is extracted with alcohol and coupled with p-nitroaniline for identification. Cachia and associates (10) claim that the infrared spectra of mixtures of two and three plasticizers are often insufficient to allow complete identification. They used column chromatography to separate and recover the plasticizers in most cases, but were unable t o separate dialkyl phthalates from other dialkyl esters. Harkins, Harris, and Shreve (46) illustrated the identification of paint pigments by infrared spectroscopy with 21 spectra of inorganic and five spectra of organic pigments. They listed those pigments showing no characteristic absorption bands and indicated the importance of having a library of reference spectra. The spectra illustrated were obtained using Nujol mulls of the separated pigments. Andrens (4)has described an easily constructed, inexpensive spectrograph for use in the qualitative analysis of inorganic paint pigments including zinc chromate, barium chromate, red iron oxide, talc, and antimony oxide. The qualitative analysis of organic pigments is discussed and tabulated by Rubbi (93). He first dissolves the pigment by boiling successively for a few minutes with benzene, 2Y0 sodium carbonate, 10% hydrochloric acid, and sodium persulfate. The phthalocyanines are left as an insoluble residue. A series of simple tests is used to complete the identification.
LITERAIURE CITED
(1) Adams, M. L., Swann, M. H., O&c. Dig. Federation Paint & Varnish Production Clubs 31, 1247 (1959). (2) Anderson, D. A,, Freeman, E. S., ANAL.CHEM.31,1697 (1959). (3) Anderson, W. M., Carter, G. B., Landau, A. J., Ibid., p. 1214. (4) Andrews, G. M., J . Oil & Colour Chefisists’ Assoc. 42, 261 (1959). (5) Arendt, I., Schenck, H. J., Kunststo$e, 48, 111 (1958). (6) Ayres, 1%’. PI., Whitnack, G. C., ANAL. CHEW32, 358 (1960). (7) Beitchman, B. D., J . Research Natl. Bur. Standards 63, 189 (1959). (8) Burleigh, J. E., McKinney, 0. F., Barker, M. G., ANAL. CHEM.31, 1684 (1959). (9) Burley, R. A,, Bennett, W.J., Appl. Spectroscopy 14, 32 (1960). (10) Cachia, M., Southwart, D. W., Davison, Vi’. T., J . Appl. Chem. 8 , 291 (1958). (11) Can. Paint & Varnish Mag. 33, 50 119591. (12) Challa, G., Hermans, P. H., ANAL. CHEM.32,778 (1960). (13) Chiang, M. T., Bobalek, E. G., Ofic. Dig. Federation Paint & Varnish Productton Clubs 31, 1287 (1959). (14) Claver, G. C., ‘ Murphy, M. E., ANAL.CHEM.31. 1682 11959). (15) Corish, P. J.,’Ibid.,p. 1298. (16) Craig, B. hl., Murty, N. L., Can. J . Chem. 36, 1297 (1958). (17) Craig. B. M.. Murtv. S . L., J . Am. Oil ChGists’ Soc. 36, 649 (1958). (18) Dahman, E. A. M.,van der Laarse, J. D., Z . anal. Chem. 164, 37 (1958). (19) Dannenberg, H., Forbes, J. W., Jones, A. C., ANAL. CHEY. 32, 3 6 5 (1960). (20) DeAngelis, G., Ippoliti, P., Spina, N., Ricerca sci. 28, 1444 (1958). (21) Deeleman, P. R., van der Schee, A . C., Verfkroniek 32,261 (1959). (22) Dijkstra, R., Lammers, M. F., Rec. trav. chim. 7 7 , 933 (1958). (23) Dmitrieva, V. N.,Bezuglyi, V. D., Zavodskaya Lab. 25, 555 (1959). (24) Durbetaki, A. J., AXAL. CHEM.30, 2024 (1958). (25) Emmerling, John, Ofic. Dig. Federation Paint & Varnish Production Clubs 30, 1172 (1958). (26) Esposito, G. G., Ibid., 32, 67 (1960). (27) Esposito, G. G., Swann, M. H., ANAL.CHEM.32., 49 (1960). ~ , (28) Ibid., p. 680. (29) Feigl, Fritz, Anger, Vinzenz, Modern Plastics 37, 151 (1960). (30) Feigl, F., Jungreis, E., ANAL. CHEhi. 31, 2099 (1959). (31) Fenton, A. J. Jr., Crisler, R. O., J . Am. Oil Chemists’ SOC. 36, 620 f1959’I. \ - - - - ,
(32) Fertig, J., J . Appl. Polymer Sci. 2, 125 (1959). (33) Fijolka, P . , Kayler, R., Lenz, I., Kunststofle 49,222 (1959). (34) Freegarde, M , Jones, B., Analyst 84, 396 (1959). (35) ,Frehden, O., Piicolescu, Z., Rev. chzm. (Bucharest) 9, 688 (1958). (36) Gar‘don, J. L., ‘Leopold, B., ANAL. CHEX.30, 2057 (1958). (37) Genge, C. A., Ibid., 31, 1750 (1959). (38) Glass, C. A., Melvin, E. H., J. Am. Oil Chemists’ SOC.36, 100 (1959). (39) Goddu, R. F., Delker, D. A., ANAL. CHEX 30, 2013 (1958). (40) Golosova. L. V., Zhur. Anal. Khim. 14, 748 (1959). (41) Greger, K. M., Szmrecsanyi, I. V., Bodi, E. M., Magyar Kem. Lapja 15, 72 (1960). ~
(42) Grimmer, J., Chem. prztmysl 9, 444 (1959). (43) Grisenthwaite, R. J., Brit. Plastics 32, 428, 4L9 (1959). (44) Hall, hi. E., hlcyutt, It. C,., . 4 ~ . 4 ~ . CHEM.32, YO73 (1960). (45) Hanson, K. W., J . Oil S Colozir Chemists’ Aisoc. 41, 203-257 (19.58). (46) Harkins, T.R., Harris, J. T., Shrew, 0. D., ANAL.CHEX. 31, 541 (1959). (47) Haslam, J., Hamilton, J . B., Squirrel, D. C. M., J . - 4 p p l . Chem. 10, 97 (1960). (48) Haslam, J., Jeffs, A. It., Analyst 83, 455 (1958). (49) Hcrrlinger, It., J . At?&,Oil Chemists’ Sot. 36, 119 (1959). (50) Hilton, C. L., Newell, J. E., Tolsma, J., ANAL.CHEM.31, 915 (1959). (51) Hilton, C. L., Newell, J. E., Tolsma, J., Rubber Age 85, 783 (1959). (52).Hilton, C. L., h . 4 ~CHEX. 31, 1610 (1959). (53) Ibid., 32, 383 (1960). (54) Him, C. F., Lucchesi, C. A,, Ibid., 31, 1417 (1959). (55) Hitchcock, R. D., U. S. Naval Civil Engineering Lab. Rept. PB161326, Sept. 1959. (56) Hobden, F. W.,J. Oil 82 Colour Chemists’ Assoc. 41, 24-41 (1958). (57) Holman, R. T., Eurr, S., Edmondson, P. R., Arch. Riochem. Biophys. 80, 72 (1959). (58) Hornstein, I., Elliott, I,. E., Cron-e, P. F.,Nature 184, 1710 (1959). (59) Hudy, J. A., ANAL. CHEM. 31, 1754 (1959). (60) Huhn, H., Jenckel, E., 2. Anal. Chem. 163,427 (1958). (61) Hummel, Dieter, Farbe u. Lack 65, 440 (1959). (62) Kappelmeier, C. P. A., “Chemical Analysis of Resin-Based Coating Materials,” Interscience, New York, 1959. (63) Kaufmann, H. P., Makus, Z., Fette, Seifen, Anstrichmittel 62, 153 (1960). (64) Kijima, R., Ueno, H., J . Chem. SOC. Japan, Znd. Chem. Sect. 61, 270 (1958). (65) Kline, G. M.,“Analytical Chemistry of Polymers,” Part 1, Interscience, New York, 1959.
(66) Iirzeminski, Z. S., Paint J . .411stralia and New Zealand 4, 19 (1959). (67) Kubota, T., Takamura, T., Bull. Chem. SOC.Japan 33, TO (1960); in English. (68) Kuta, E. J., A I ~ A L .CHEJI. 32, 1065 (1960). (69) Kveton, R., Skalova, A., Chem. Prdmysl 9, 416 (1950). ( T O ) Lady, J. €I., Boivcr, G. M., Atlams, R. E., Byrne, F. P.,ANAL. CHEJI. 31, 1100 (1959).
(71) Langford, \V. J., Vaughan, D. J., .?’atwe 184, 116 (1959). (72) Langford, W. J., Vaughan, 1). J., J . Chromatog. 2, 564 (1959). (73) Langmaier, F., Much, E., Kokes, D.,
Collection Czechoslov. Chem. Co?wnuns. 24, 2066 (1959); in German. (74) Lehrle, R. S., Robb, J. C., Suture 183,1671 (1959). (75) Link, W. E., J . A m . Oil Chemists’ SOC.36, 477 (1959). (76) Luther, H., hleyer, H., Loew, H., 2. anal. Chem. 170, 155 (1959). (77) Madorsky, S. L., Straus, Sidney, J . Research Natl. Bur. Standards 63A,
261 (1959). (78) Mano, E. B., ANAL.CHEM.32, 291 (1960). (79) Marwedel, Georg, Farbe u . Lack 66, 63 (1960). (80) hlehlenbacher, V. C., “The Analysis Fats and Oils,” Garrard Press, Champaign, Ill., 1960. (81) Murakami, T., Japan Analyst 7, 304 (1958). (82) Noll, W.,Damm, K., Krauss, W., Farbe u. Lack 65, 17 (1959). (83) Normitz, George, Ofic. Dig. Federation Paint & Varnish Production Clubs 31, 441 (1959). (84) Orr, C. H., Callen, J. E., Ann. 4. Y . Acad. Sci., 72, 649 (1959). (85) Paint Manuf. 29, 174, 374 (1959). (86) Ibid., 30, 179, 366 (1960). (87) Paint Varnish Production 49, 147 (1959). (88) Zbid., 50, 165 (1960). (89) Paquot, P., Olearia 11, 5 (1957). (90) Radell, E . A,, Strutz, H. C., ANAL. CHEM.31, 1890 (1959). (91) Rhodes, D. N., J . Appl. Chem.
(London) 10, 122 (1960). (92) Rosenberger, H. hl., Shoemaker C. J., ASAL.C H E ~31, I . 1315 (1959). (93) Rubbi, P., Pilture e uernici 15, 65 (1959). (94) Ryabov, A. V., Tarakanov. 0.G., Trudv Khim. i Khiin. Tekhnol. 1958, S o . 2,423. (95) Sadowski, F., Kagner, € I . , Plaste u. Kautschuk 7, 103 (1960). (96) Schroder, E., Ibid., 5 , 49, 103 (1958). (97) Ibid., 6, 325 (1959). (98) Schroder, E., Thinius, I
