Template Polymerization of a Novel Cationic Polyacrylamide: Sequence Distribution, Characterization, and Flocculation Performance

In this study, the template polymer (TPDA) of dimethyldiallylammonium chloride (DMD) and acrylamide (AM) was synthesized with UV-initiated template polymerization. The reactivity ratio, Fourier transform infrared spectroscopy, 1H NMR spectroscopy, and thermogravimetric analysis were employed to characterize the TPDA properties. The results revealed that the addition of template sodium polyacrylate improved the reactivity ratio of DMD and increased the number and length of DMD segments in polymer molecules. The results of flocculation tests demonstrated that the DMD block structure improved the flocculation performance of TPDA, especially charge neutralization. In the optimal conditions of a TPDA dose of 9.0 mg·L–1 and a wastewater pH of 5.0–7.0, the residual concentration of suspended solids in a supernatant of coal mine wastewater reached the lowest value of approximately 20.04 mg·L–1. The TPDA flocs were large, compact, rapid to settle, and difficult to restabilize.