Study on preparation and flocculation performance of cationic polyacrylamide-starch graft copolymers

Three cationic polyacrylamide-starch graft copolymer flocculants,ZHYC-n,with different cationic charge density were prepared.When the mass ratio of acrylamide to starch is more than 2.0,the graft frequency is not increased markedly while the relative molecular mass of side chain is increased.The flocculation performance of these flocculants was determined and compared with the typical cationic flocculant CPAM.The experimental results indicate that the flocculation effect increases with the cationic charge density of the flocculants increasing.The flocculation efficiency of ZHYC-70 is about 30 times more than that of the CPAM.But cationic charge density in molecular chain of flocculants is not unique dominating factor affecting the flocculation effect.Multi-side-chain structure of cationic starch graft copolymer flocculants can improve flocculation effect markedly.