Alkaline hydrolysis of polyacrylonitrile, 1 - Structure of the reaction products

The alkaline hydrolysis of a polyacrylonitrile suspension was carried out i n a water/ethanol mixture at 75 degrees C. The product structure was studie d by means of solid state C-13 NMR spectroscopy. The hydrolyzed samples con tain up to 20% of amidines, which are formed in the nearest neighborhood of the COONa groups. Amidines are relatively stable under the given reaction conditions up to almost complete conversion of the nitrile groups, then bei ng hydrolyzed gradually into amides. After complete hydrolysis of the amidi nes, the resulting poly[(acryl amide)-co-(sodium acrylate)] exhibits a Bern oulli triad distribution of the comonomer units. The data obtained might be useful in elucidating the reaction mechanism.