Anal. Chem. 1986, 58,3188-3195
3188
nearly identical calibration curves, a single calibration curve can be used for the determination of structurally different organic cyanates. ACKNOWLEDGMENT We thank J. Davis for his help with the ‘HNMR spectra and S. D. Maleknia for providing the field desorption mass spectrometry. We also acknowledge the advice and help of M. Marletta and C. E. Costello in preparing this manuscript. Registry No. 2, 50962-50-0;3, 104549-45-3;4, 1122-85-6;6, 1156-51-0;7,93174-01-7;8, 104549-44-2;DBA, 769-42-6;pyridine, 110-86-1. LITERATURE C I T E D Martin, Dieter Angew. Chem. 1964, 7 6 , 303 (or Angew. Chem., I n t . Ed. Engl. 1964, 3 , 311). Jensen. Kai A,: Due, Marie; Holm, Arne Acta Chem. Scand. 1965, 19. 438-442.
&gatlErns< Putter, Rolf Chem. Ber. 1964, 9 7 , 3012-3017. The Chemistry of Cyanates and Their Thio Derivatives; Patai, S . , Ed.: Wiley: New York, 1977. Hedayatullah, Mir; Denivelle, Leon C . R . Acad. Sci., Ser C 1969, 268, 427-429. Martin, Dieter; Bacaloglu, Radu Organische Synfhesen mit Cyansaureestern: Akademie-Verlag: Berlin (East), 1980. Kagedai, Lennart: Akerstrom. Stig Acta Chem. Scand. 1970, 2 4 , 160 1-1 608. Kohn, Joachim, Lenger, Reuben: Wilchek. Meir Appl, Biochem . Biofechnol. 1983, 8 , 277-235. Powers, James C.; Tuhy, Peter M.: Witter. Frank Biochim. Biophys Acta 1976, 445, 426-436.
Martin, Dieter: Bacaloglu, Radu Organische Synthesen mif Cyans&reestern ; Akademie-Verlag: Berlin (East), 1980; p 25. Minnesota Mining and Manufacturing Co. Br. Patent 1 305 762, 1973. , Farbenwerke Bayer (West Germany). US. Patent 3491 060, 1970. (13) Kohn, Joachim; Langer, Robert Biomaterials 1986, 7 , 176-182. 114) Farbenwerke Baver (West Germanv). Ger. Patent 1220 132. 1964. Ben-Efraim, Davib A,’ I n The Chem/stiy of Cyanates and Their Thio Derivatives; Patai, S . , Ed.; Wiley: New York, 1977; Chapter 5. Konig, W. J . Prakt. Chem. 1904, 69, 105-110. Schwarzenbach, G.; Weber, R. Helv. Chim. Acta 1942, 2 5 , 1628-1639. Meites. Louis Handbook of Analytical Chemistry. 1st ed.; McGraw-Hill: New York, 1963; pp 6-67. Lambert, Jack L.; Ramasamy, Jothi; Paukstelis, Joseph V. Anal. Chem. 1975, 4 7 , 916-918. Wilchek, Meir; Miron, Talia; Kohn, Joachim Anal. Biochem. 1981, 774, 419-421. Kohn. Joachim; Wilchek, Meir J . Chromatogr. 1982, 240, 262-263. Kohn, Joachim; Wiichek, Meir Anal. Biochem. 1981, 715, 375-382. Becher, Jan Org. Synth. 1980, 5 9 , 79-84. Kohn, Joachim: Langer, Robert J . Am. Chem. Soc., in press. Eastman Kodak Co. U.S. Patent 3 879 678, 1975. Minnesota Mining and Manufacturing Co. Br. Patent 2 136 590, 1984. Waggoner, A. S. Ann. Rev. Biophys. Bioeng. 1979, 8 , 47-68. Feigl, Fritz; Anger, Vinzenz Spot Tests in Inorganic Chemistry, 6th ed.; Elsevier: New York, 1972; p 4. Odian, George Principles of Polymerization, 2nd ed.; Wiley-Interscience: New York. 1981; p 55.
RECEIVED for review May 20,1986. Accepted July 17,1986. This work was supported by NIH Grant GM 26698. The MIT Mass Spectrometry Facility is supported by NIH Grant RR 00317 (to K. Biemann).
Identification of Organic Additives in Rubber Vulcanizates Using Mass Spectrometry R. P. Lattimer,* R. E. H a r r i s , a n d C. K. Rhee T h e BFGoodrich Research and Development Center, Brecksville, Ohio 44141 H.-R. S c h u l t e n Fachhochschule Fresenius, 6200 Wiesbaden, Federal Republic of Germany The identification of the Ingredients in a compounded polymer is often a complex task for the analytical chemist. A wlde variety of components are involved-polymers, fliiers, soivents, and organic and inorganic addltives. This report considers the IdentHicatlon of organic additives in rubber vulcanizates by various mass spectrometric methods. Direct thermal desorption has been used with three different ionization methods (electron impact, EI; chemical ionlzatlon, CI; fleld ionization, FI). The vukanlzates were also examlned by direct fast atom bombardment mass spectrometry (FARMS) as a means for surface desorptkn/lonitatkn. Rubber extracts were examined directly by four ionization methods (EI,CI, FD, FAB). Of the various vaporlzatlon/ionizatlon methods, It appears that field desorption/ionizatlon (FD/FI) is the most efficient for identifying typical organic additives in rubber vuicanirates. Other Ionization methods may be requlred, however, for detection of speclfic types of additives. I n this study there was no clear advantage for dlrect analysis as compared to extract analysis. Dhect analysis Is a Httle faster, but extraction methods are more versatile. Mass spectrometry is a very effective means for the rapid Identification of organic additives in rubber vuicanizates.
The identification of the ingredients in a compounded polymer is a difficult task for the analytical chemist. A wide 0003-2700/86/0358-31S8$01.50/0
variety of components are involved-polymers, fillers, solvents, and organic and inorganic additives. Various methods have been developed to separate, identify, and quantify the numerous ingredients. Our laboratory is in the process of evaluating new or improved techniques for analysis of compounded polymers. Considerable effort in this regard is being focused on mass spectrometry as a means to supplement and extend our current analytical methods. We are particularly interested in direct methods of analysis, i.e., examining the polymer with no or minimal pretreatment of the sample ( 1 ) . In this report we will consider the identification of organic additives in rubber vulcanizates by various mass spectrometric methods. This general topic has been the subject of a recent review (2). The identification of additives in compounded polymers is made complex by a number of factors (2): (1) There are a wide variety of additive types; many compound classes are represented. Additives differ greatly in molecular weight, volatility, and polarity. Some additives are pure compounds, while others are complex oligomeric mixtures. (2) Many additives are labile. Accelerators and other curatives decompose during processing of the polymer. Various stabilizers are designed to be reactive during the useful lifetime of the polymer. (3) Complex mixtures of additives will normally be present in a compounded polymer. Some additives may interact chemically with each other and/or with the polymeric components. (4)Organic additive concentrations may be quite low (
