The succinylation of cornstarch by extrusion processing has been studi
ed. Several different factors affecting the succinylation of starch we
re investigated including water content, succinic anhydride quantity,
catalyst type and quantity, and reaction temperature. The degree of su
bstitution (DS) increases with decreasing water content and increasing
succinic anhydride quantity. Higher temperature favors higher DS usin
g sodium bicarbonate as catalyst while the opposite is true using magn
esium hydroxide as catalyst. Of the three catalysts used, sodium bicar
bonate is best. Aqueous solubility and viscosity of the starch succina
tes tend to increase with increasing DS. Based on the results of aqueo
us solution viscosity, some samples appear to be promising as commerci
al thickening agent.