HPLC Determination of Emission Quantity of 2 Diisocyanates in Polyurethane Adhesives after Application

HPLC was applied to the determination of emission quantity of 2 diisocyanates, i.e. 2,6-TDI and HDI in polyurethane adhesives after application. The sample of polyurethane adhesive was spread on a glass plate, which was then put into the environmental chamber. Glass fiber filter membranes impregnated with 1-2MP were used for air sampling. The filter membranes were removed and put in a bottle. 0.2 mol·L^-1 1-2MP toluene solution, ethyl acetate and acetic anhydride were added in the bottle. Hypersil ODS chromatographic column was used as stationary phase, and a mixture of acetonitrile and acetic acid-sodium acetate buffer solution of pH 6.0 (33+67) was used as mobile phase. Detection at 242 nm was adopted in the determination. Linear relationships between values of peak area and mass concentration of 2,6-TDI and HDI were kept in the same range within 20.0 mg·L^-1, with detection limits(3S/N)of 0.020, 0.040 mg·L^-1, respectively. Values of recovery found by standard addition method were in the range of 81.4%-101%, and values of RSDs (n=6) were in the range of 1.1%-6.6%.