SOME STUDIES ON STARCH CARBAMATE

Starch carbamate was prepared by reacting maize starch with urea using solid state technique. The different factors affecting this reaction were studied. These Factors include urea concentration, type of starch , reaction and duration. The carbamate extent and carbamation reaction efficiency (%) were traced by estimating the nitrogen content of the reaction product. Solubility, viscosity and total ester content of sta rch carbamate samples were estimated. The carbamate extent increases b y increasing urea concentration as well as reaction temperature and du ration. Increasing the reaction temperature and duration has the same effect on carbamation reaction efficiency (%), while increasing urea c oncentration do the reverse. The solubility (%) of starch carbamate sa mples depends on urea concentration, reaction temperature and duration as well as the type of starch used. The maximum solubility obtained w as 63% and 43% for starch carbamate derived from pregelled and native starch, respectively. Tentative mechanism for the reaction between sta rch and urea has been proposed.