TECHNOLOGICAL EVALUATION OF STARCH BEARING AROMATIC AMINO-GROUPS AS CATIONIC EXCHANGER

Starch bearing aromatic amino groups was prepared by first reacting cy anuric chloride with p-nitroaniline to obtain 2[p-nitroanilino] 4,6-di chloro-s-triazine (compound I). The latter was then reacted with starc h. The aromatic nitro group in this reaction product was converted to aromatic ammo group via reduction using thioureadioxide as a reducing agent. The extent of the reaction of compound I with starch (expressed as nitrogen content as well as ion exchange capacity) was found to be increase by increasing compound I concentrations and by prolonging th e duration as well as by raising the reaction temperature up to 50-deg rees-C. Higher temperatures exert either no or an adverse effect; whil e reaction temperature of 60-degrees-C has no significant effect on th e reaction extent, the latter falls substantially at temperature highe r than 60-degrees-C, indicating partial splitting of the aromatic amin o groups and/or hydrolysis of the active chlorine under the influence of alkali and heat. The ion exchange capacity of starch bearing aromat ic amino groups is essentially governed by the amount of the amino gro ups and, to some extent, by the technique employed for the introductio n of these groups in the molecular structure of starch. An ion exchang e capacity as high as 189 meq./100 g sample could be achieved.