A novel preparation method of polyaluminum chloride/polyacrylamide composite coagulant: Composition and characteristic

Inorganic/organic composite coagulants have drawn a wide attention through the years owing to its superior coagulation behaviors. In this study, polyaluminum chloride (PAC)/polyacrylamide (PAM) composite coagulant was synthesized by ultraviolet (UV) irradiation by using PAC and acrylamide (AM) as raw materials, urea as a solubilizer, and 2,2′‐Azobis2‐(2‐imidazolin‐2‐yl)propane]dihydrochloride (VA‐044) as an initiator. The effect of total monomer mass fraction, solubilizer dosage and initiator dosage on the viscosity and molecular weight of PAC/PAM composite coagulant was discussed. The results suggest that the composite coagulant with high polymerization degree, intrinsic viscosity of 1483 mL/g and molecular weight of 7.38 million, could be obtained when the total monomer mass fraction of 40%, urea dosage of 1.5% and initiator dosage of 0.6% are chosen in the preparation. It is a potential preparation method of composite coagulant with short preparation time and high preparation efficiency. Fourier transform infrared spectrum and ¹H nuclear magnetic resonance spectroscopy represent that the coagulant for polyaluminum chloride and polypropylene are copolymer. Thermal gravimetric analysis describes the high thermal stability of composite coagulant. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44500.