Hydrophobically Associating Polyacrylamides Prepared by Inverse Suspension Polymerization: Synthesis, Characterization and Aqueous Solution Properties

Hydrophobically associating polyacrylamides (HAPAMs) were synthesized via inverse suspension polymerization using ammonium persulphate (APS)/tertramethylethylenediamine (TEMED) as the redox initiators, 2-methacryloyloxyethyl n-alkyl dimethyl ammonium bromide (DM-n, n = 8, 12, 16) as the hydrophobic comonomers. The structures of the copolymers were elucidated by FT-IR and ionic chromatographic analysis, respectively. The morphology and particle size of the resultant HAPAMs were characterized by scanning electronic microscope (SEM) and laser particle size analyzer, which revealed that spherical particles were formed and the particle size exhibited Gaussian distribution centered from 25 m to 162 m. Furthermore, the solution properties of the copolymers were studied with viscometry and the results showed that HAPAMs synthesized under optimal conditions exhibited an obvious viscosity enhancement in aqueous solution and excellent salt-tolerant capability in brine.