Abstract
The determination of residual acrylonitrile (AN) in acrylonitrile styrene copolymers (AS) and acrylonitrile butadiene styrene copolymers (ABS) was studied.
AS and ABS were dissolved in 20ml of dimethylformamide (DMF). AN and DMF were vaporized by heating on a mantle heater so as to give a distillation rate of about 1.5ml/min. They were collected in a test tube of DMF (4ml) containing 100μg of benzene (internal standard) under a nitrogen gas flow of 60-80ml/min until 10ml had been obtained.
The concentration of AN in the test tube was determined by mass fragmentography, using selected ion recording at m/e 52, together with the internal standard.
The recoveries of AN from AS and ABS in the range of 10.0 to 20.0μg were 92-103% and 95-103%, respectively. The coefficient of variation did not exceed 2%. Commercial AS and ABS were analyzed and found to contain 4-110 ppm AN.
