Comparative study of synthetic methods of cassava starch grafted acrylamide flocculant

Abstract

Starch graft acrylamide flocculant (St-PAM) was prepared by solution polymerization and inverse emulsion polymerization using cassava starch and acrylamide monomer as raw materials, and the properties were compared. The results show that the monomer conversion and grafting rate of St-PAM prepared by inverse emulsion polymerization are higher than those of solution polymerization with the same reaction temperature and monomer ratio, and less initiator is needed, which is beneficial to cost saving. The graft copolymerization degree of St-PAM synthesized by inverse polymerization method is higher than that of solution polymerization, and it has deeper surface roughness and more wrinkles, which is more conducive to adsorption and net trapping, and has stronger thermal stability. St-PAM synthesized by inverse emulsion polymerization has stronger adaptability to temperature and pH, and lower demand for stirring time and stirring speed. Under the same conditions, the highest flocculation rate of St-PAM prepared by solution polymerization is about 85%, while that of St-PAM prepared by inverse emulsion polymerization is more than 90%, indicating that the performance of St-PAM prepared by inverse emulsion polymerization is better than that of solution polymerization.

Keywords

• cassava starch
• acrylamide
• solution polymerization
• inverse emulsion polymerization
• flocculation rate