Determination of Free-formaldehyde in Adhesivesby Gas Chromatography

A method for the determination of free-formaldehyde in adhesives by ultrasonic extraction, 2,4-dinitrophenylhydrazine derivatization, and gas chromatography coupled with electron capture detection (GC-ECD) has been developed. Optimum conditions of extraction, derivatization and chromatography were studied. The detection limit of this method for formaldehyde was 0.175 μg/g. The linear range was 0.1~60.0 μg/mL, R²=0.9999. The recoveries ranged from 98.97％to 102.24% at 1, 2 and 8 μg/mL. The relative standard deviation of formaldehyde content determined by 5 laboratories was 4.0%. Results showed that the method is convenient, rapid, and with low detection limit, high recovery and high repeatability.