A straightforward and novel methodology has been developed for the synthesis of ultra-high-molecular weight polyacrylamide (PAM) by vertical solution polymerization technique. By varying the concentrations of acrylamide monomer, three different grades of polymers (PAM-V-1, PAM-V-2, and PAM-V-3) have been synthesized and compared with the series of different grades of PAM (PAM-C-1, PAM-C-2, and PAM-C-3) synthesized through conventional solution polymerization technique. The synthesized grades PAM-V-1, PAM-V-2, PAM-V-3, PAM-C-1, PAM-C-2, and PAM-C-3 have been characterized by H-1 NMR, infrared spectroscopy, intrinsic viscosity measurement, molecular weight determination by gel permeation chromatography, and thermal analysis. Rheological analysis has been carried out on the aqueous solutions of various grades of PAMs. Swelling behavior of ultra-high-molecular weight PAMs has also been investigated. The flocculation performances of all grades have been investigated in kaolin suspension by settling and jar test methods. POLYM. ENG. SCI., 59:1175-1181 2019. (c) 2019 Society of Plastics Engineers