Microwave-assisted Synthesis of Acrylamide Grafted Polymeric Blend of Fenugreek Gum and its Characterization

Objective: In this study, fenugreek gum (isolated from fenugreek seed) was modified into a grafted form using a microwave-assisted method. Acrylamide was used as a monomer, and ceric ammonium nitrate (CAN), potassium persulfate (KPS), and ammonium persulfate (APS) were used as redox initiators. Methods: The experimental design (Taguchi OA) was used to optimize the synthesis of the grafted copolymer of fenugreek gum. In this model, seven independent variables were selected on the basis of their preliminary study. These were monomer concentration (X1), gum concentration (X2), initiator concentration (X3), irradiation power (X4), speed (X5), time (X6), temperature (X7), and three response variables as % yield (Y1), % grafting (Y2), and % grafting efficiency (Y3) were identified. The optimized copolymers of grafted gum were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), NMR studies, surface morphology and swelling index. Results: The yield of fenugreek gum after extraction was found to be 55.99±0.015% w/w. The percentage grafting of 50.20±4.0, along with grafting efficiency of 83.7±0.1, was obtained with the selected concentration of acrylamide as 15 mg, grafted gum as 0.25 mg, and ammonium persulfate as 0.2 mg after 60 sec. of irradiation time. Conclusion: In the present study, the graft copolymers of fenugreek gum were synthesized. After optimization of the grafting batch, the design (Taguchi OA) was combined with a desirability function. The results underline the importance of graft polymerization techniques for modifying the properties of a polymer.