Synthesization of Modified Starch and Its Performance

Carboxylmethylic starch,cationic starch and multi group starch were synthesized, and the electroegativity of molecular polar groups of the products and three hydrophilicity hydrophobicity equilibrium parameters(HLB,lg p and i ) of reagents were calculated.The authors vestigated the affinity and electric property of the reagents' polar groups and the hydrophility-hydrophobicity criteria of the reagents,and their flotation effect on pure diaspore and kaolite.The reagents have a depressing effect on pure diaspore and kaolite in acid medium and the depressing effect decreases in the order of multi group starch, carboxymethylic starch,cationic starch and raw starch. However, they can activate kaolite, and among them carboxylmethylic starch and cationic starch have a stronger activating effect on kaolite.The results obtained by the study on the relationship between modified starch's structure and performance are in accord with ones obtained by the flotation test.