Characterization of poly(acrylamide-co-acrylates) obtained by inverse microemulsion polymerization

Abstract

Two series of poly(acrylamide-co-acrylates) with compositions ranging from 10 to 55 mol % acrylate units were prepared by radical polymerization in inverse microemulsions. The compositional analyses of the samples were performed using elemental analysis, potentiometry and 13C NMR. The comparison between the three methods indicates that "C NMR is the most reliable one, avoiding errors which often arise from assodated water in hydrophilic polymers. The copolymer viscosity exhibits a maximum behavior around 40 mol % acrylate content, a lower value than that already observed for copolymers prepared in homogeneous solution. The production of copolymers presenting high intrinsic viscosities (-3700 cm3g -1) is achieved using an inverse microemulsion as the polymerization medium operating at lower temperature.

Shear Viscosity of Poly (Acrylamide/Acrylic Acid) Solutions

“…Besides shear viscosity, intrinsic viscosity also varies with copolymer composition. Candau et al studied the intrinsic viscosity of AAm/NaAc copolymer with respect to the NaAc content in the copolymer and observed a maximum in intrinsic viscosity of the solution around 40% (molar) of NaAc . They explained it based again on electrostatic interactions and hydrogen bonding within the copolymer chains.…”

Design of Tailor‐Made Water‐Soluble Copolymers for Enhanced Oil Recovery Polymer Flooding Applications

“…However, there is a limiting copolymer composition, above which the shear viscosity decreases with further increases in the AAm fraction in the copolymer. This can be explained by the fact that having less AAc decreases the probability of intramolecular hydrogen bonding and chain stiffness, which affects shear viscosity …”

Water-swellable polyelectrolyte microgels polymerized in an inverse microemulsion using a nonionic surfactant

“…7 is a schematic model of the IMEP system. Candau et al [30] reported that the molecular weight of polymers synthesized in a confined space (as in inverse microemulsion polymerization) tend to become larger than the value obtained by conventional polymerization, due to a cage effect. Moreover, in some cases, polymers synthesized in a confined space grow as single chains in that space.…”