Synthesis of graft copolymers of acrylamide for locust bean gum using microwave energy: swelling behavior, flocculation characteristics and acute toxicity study

Abstract

The graft copolymer of locust bean gum (LBG) and acrylamide has been synthesized by microwave assisted method using potassium persulphate (KPS) as an initiator in aqueous medium. Different reaction parameters such as time, initiator concentration, monomer concentration, polymer concentration, and microwave power were studied to get maximum graft copolymer. The grafted copolymer was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). The graft copolymer exhibited pH switching on-off behavior depending on the pH of the external medium. Flocculation capacity of LBG and LBG-graft-polyacrylamide for both coking and non-coking coals has been studied. Results indicated that the graft copolymer exhibited good flocculation properties compared to native polymer. The graft copolymer was non-toxic in the acute toxicity study, since the acute single dose did not cause any toxic signs, or symptoms. All mice treated with the graft copolymer survived beyond the 14 days of observation period.

Keywords

• biopolymers
• grafting reaction
• microwave synthesis
• flocculation
• swelling