Intrinsic viscosity, surface activity, and flocculation of cationic polyacrylamide modified with fluorinated acrylate

A novel cationic polyacrylamide modified with fluorinated acrylate had been synthesized of acrylamide (AM), methacryloxyethyl trimethylammonium chloride (DMC), and 2-(perfluorooctyl)ethyl acrylate (FEA) by free radical micellar copolymerization in aqueous solution utilizing cetyl trimethylammonium bromide (CTAB) as the surfactant and potassium persulfate (KPS)/sodium bisulfite (SBS) as the redox initiator. Some factors affecting synthesis, such as the amount of FEA, CTAB, and KPS, were described. Surface activity and flocculation of the polymer were studied. The results showed that with the incorporation of FEA, the intrinsic viscosity decreased until the modified polymer was not able to dissolve in water; and with the increase of CTAB and KPS, the intrinsic viscosity decreased firstly then increased slowly. The polymer exhibited good surface activity in both water and salt solution. Its flocculation properties were evaluated with kaolin suspensions using a standard jar test. The results demonstrated the superiority of the copolymer over the no-modified cationic polyacrylamide as a flocculant.