Synthesis of sulfonated copolymers of acrylamide by plasma-initiated copolymerization using microwave plasma

The copolymers of acrylamide (AM) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS) were obtained by plasma-initiated copolymerization in water solution. The effects of plasma parameters include discharge time and discharge power on the intrinsic viscosity ([η]) of synthesized copolymers were studied. The copolymers were characterized by proton nuclear magnetic resonance spectroscopy (1H-NMR) and fourier transform infrared spectroscopy (FTIR) methods. The thermal behaviour of copolymers was also investigated by thermogravimetric analysis (TGA). The results of [η] measurements as function of discharge power indicated an optimum of 27.12 dl/g at 150W of discharge power and after that [η] started to decrease. Also the measurements of [η] for different discharge time were carried out and showed an optimum of 26.03 dl/g at 30s of discharge time. The TG data showed two stages of the weight loss which the first one occurred between 270°C and 330°C, with a weight loss about 40%, and the second one happened between 350°C and 460°C, with a weight loss about 25%, respectively. The presented results show that the produced copolymers are suitable for application in enhanced oil recovery process.