Determination of Acrylonitrile Monomer in

Residual amounts of styrene and acrylonitrile monomers usually remain in manufactured batches of styrene-acrylonitrile copolymers and acrylonitrile-butadiene-styrene terpolymers (ABS), As these copolymers have a potential use in the food packaging field, it is necessary to ensure that the content of both of these monomers in the finished copolymers is below a stipulated level. In a polarographic procedure [9, 10] for determining acrylonitrile (down to 2 ppm) and styrene (down to 20 ppm) monomers in styrene-acrylonitrile copolymer, the sample is dissolved in 0.2 M tetramethylammonium iodide in dimethyl formamide base electrolyte and polarographed at start potentials of -1.7 V and -2.0 V, respectively, for the two monomers. Excellent results are obtained by this procedure. Table 5.3 shows the results obtained for determinations of acrylonitrile monomer in some copolymers by the polarographic procedure. 

Table 7.27 shows the results obtained in determinations of acrylonitrile monomer in some copolymers by the polarographic procedure. Comparison of ftiese results with those obtained by the dodecyl mercaptan procedure show that acrylonitrile contents some 30 per cent higher are obtained by the latter method. 

Determination of Acrylonitrile Monomer in Acidic and Alkaline Extractants... 

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