Synthesis and Solution Behavior of Comb-Like Terpolymers with Poly(ethylene oxide) Macromonomer

A novel macromonomer: p-vinylbenzyl-terminated octylphenoxy poly(ethylene oxide) (polymerization number: 18) (VBPEO) was synthesized. The comb-like acrylamide-based terpolymers (PVEA) were synthesized by aqueous free-radical copolymerization technique using acrylamide (AM), VBPEO and sodium 2-acrylamido-2-methylpropane sulphonate (NaAMPS). The macromonomer and PVEA polymer were characterized with Fourier transform infrared (FTIR) spectroscopy and proton nuclear magnetic resonance ((1)H NMR). The polymers exhibited self-assembly behavior in water and the brine solutions. The polymers could be employed in the oil reservoirs of either the high or medium to low permeability due to the low intrinsic viscosities. The optimum NaAMPS feed amount could not only increase the water solubility, but also facilitate the intermolecular associations. Implementing VBPEO into the polymer greatly increased the rigidity of molecular chains, resulting in a high apparent viscosity of the PVEA in water and the brine solutions. The PVEA brine solutions exhibited both excellent uni- and bivalent cation resistance, salt- and heat-thickening twice, pseudoplastic behavior, and thixotropy. The SEM morphologies showed that the expanded polymer bundles as well as the associated structures with huge sizes were formed for PVEA in water and that the continuous network structures were still formed in the PVEA brine solutions. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1241-1250, 2010