Determination of hexamethylene diisocyanate-based isocyanates in spray-painting operationsPart 2.† Comparison of high performance liquid chromatography with capillary zone electrophoresis

Abstract

A capillary zone electrophoresis (CZE) approach was developed for the determination of hexamethylene diisocyanate (HDI) monomer and HDI-based oligomers. A comparison of CZE with high performance liquid chromatography (HPLC) indicates that the CZE separation completely isolates isocyanates from excess solvent, derivatizing reagent and pigment while offering a fivefold increase in sensitivity. The CZE approach allows for the quantification of HDI monomer and oligomer within a 1 min time window under the run conditions selected. For the determination of HDI-based oligomer, provided that the relative response with respect to HDI monomer is calculated, there is no significant difference (p < 0.05, n = 10) in the isocyanate air concentration when using either HPLC or CZE. The results are significant because they indicate that CZE has advantages for the determination of both HDI-based oligomer and HDI monomer generated during spray-painting operations.

References

1. S. Silk and H. Hardy, Ann. Occup. Hyg., 1996, 27, 333.
2. L. Belin, U. Hjortsberg and U. Wass, Scand. J. Work Environ. Health, 1981, 7, 310.
3. J. L. Malo, G. Ouimet, A. Cartier, D. Levitz and R. Zeiss, J. Allergy Clin. Immunol., 1983, 72, 413.
4. J. Nielsen, C. Sango, G. Winroth, T. Hallberg and S. Skerfving, Scand. J. Work Environ. Health, 1985, 11, 51.
5. O. Vandenplas, A. Cartier, J. LeSage, Y. Cloutier, G. Perreault, L. C. Grammer, M. A. Shaughnessy and J.-L. Malo, J. Allergy Clin. Immunol., 1993, 91, 850.
6. G. Tornling, R. Alexandersson, G. Hedenstierna and N. Plato, Am. J. Ind. Med., 1990, 17, 299.
7. M. Janko, K. McCarthy, M. Fajer and J. van Raalte, Am. Ind. Hyg. Assoc. J., 1992, 53, 331.
8. C. J. Purnell and R. Walker, Analyst, 1985, 110, 893.
9. V. Dharmarajan, R. D. Lingg, K. S. Booth and D. Hackathorn, in Sampling and Calibration for Atmospheric Measurements, ed. J. K. Taylor, ASTM Special Technical Publication 957, American Society for Testing and Materials, Philadelphia, PA, 1988, pp. 190.
10. S. P. Levine, K. J. D. Hillig, V. Dharmarajan, M. W. Spence and M. D. Baker, Am. Ind. Hyg. Assoc. J., 1995, 56, 581.
11. Method 42: Diisocyanates, in OSHA Methods Manual, Occupational Safety and Health Administration, Salt Lake City, UT, USA, 1994, pp. 42-1–42-39.
12. Method No. 5521: Isocyanates, Monomeric, Issue 2, in NIOSH Manual of Analytical Methods, ed. P. M. Eller, DHHS (NIOSH) Publication No. 94-113, vol. 2, National Institute for Occupational Safety and Health, Cincinnati, OH, 4th edn., 1994.
13. MDHS 25: Organic Isocyanates in Air, in Methods for the Determination of Hazardous Substances, Health and Safety Execu-tive, Occupational Safety and Hygiene Laboratory, London, 1987.
14. W. E. Rudzinski, L. Pin, R. Sutcliffe, A. Richardson and T. Thomas, Anal. Chem., 1994, 66, 1664.
15. W. E. Rudzinski, J. Yin, S. H. Norman and D. A. Glaska, Analyst, 1998, 123, 2079.
16. Desmodur N-100 Material Safety Data Sheet, Bayer, Pittsburgh, PA, 1996.