EFFECT OF DEGREE OF SUBSTITUTION ON GRAFTING OF ACRYLONITRILE ONTO SODIUM-SALT OF PARTIALLY CARBOXYMETHYLATED AMYLOSE

In order to study the effect of degree of substitution, the grafting o f acrylonitrile (AN) onto sodium salt of partially carboxymethylated a mylose (Na-PCMA) samples of varying degrees of substitution has been c arried out using ceric ammonium nitrate (CAN) as an initiator. The per centage of grafting (% G), percentage grafting efficiency (% GE) and % add-on are found to decrease with increase in degree of substitution. The molecular weights of the grafted homopolymer (PAN) have been dete rmined from viscosity measurements and are found to decrease with incr ease in degree of substitution of Na-PCMA sample, The results on the t hermal studies of all the Na-PCMA samples and their graft copolymers a lso showed that the thermal stability decreases with increasing degree of substitution of Na-PCMA.