Simultaneous anodic and cathodic polymerizations of acrylamide

Abstract

The electrolysis of acrylamide in sodium nitrate/N,N-dimethylformamide solutions leads to polymer formations simultaneously in the anode and cathode compartments. The influences of monomer concentrations. current levels, nature of some electrode metals and supporting electrolytes on polymerization were examined. Anodic polymers of high molecular weights were obtained (ca. 10'). The current-voltage curves and other experimental findings strongly suggest that the direct reduction of acrylamide at the cathode leads to the cathodic polymerization which is like the polymerization by anionic initiators in which the monomer gives a polymer of amide structure via a hydrogen transfer process. On the other hand, the anodic polymerization is possibly initiated by the species produced by the anodic reaction of the supporting electrolyte and is analogous to the free-radical polymerization of acrylamide. Infrared spectra of the polymers show that the cathodic polymer IS a polyamide (...-CH2-CH2-CO-NH-...) whereas the anodic has a C-C chain structure (...-CH2-CH(CONH2)-...).

Liquid Metal Nanoparticles as Initiators for Radical Polymerization of Vinyl Monomers

“…To characterize the polymerization product, we degrafted the polymer by etching the surface of the LMNPs with NaOH solution (1 M, 5 min) and used centrifugation to separate the LMNPs from the polymer solution (Figure S4). The FT-IR spectrum of the polymer confirms the presence of polyacrylamide (PAAm; Figure c) and rules out the formation of polyamide-3 (an anionic polymerization is highly unlikely due to the presence of water) . To confirm the polymerization of AAm we note that the CC vibration band at 1610 cm –1 in AAm decreases with progressing AAm monomer conversion .…”

Polymerization of acrylamide with nitric acid

“…It is seen from Figure 7 that the time dependence of relative viscosity of the polymerizing mixture initially exhibits an induction period of several minutes and then is followed by a sudden increase in viscosity owing to gel formation. In the viscometer the reaction mixture was transformed into a glassy mass, as was also observed in the case of NO2 initiated and electrolytically initiated polymeriza- tion of AA in water (2). The increase of monomer concentration accelerates the gelation (see Table IV).…”

“…The increase of monomer concentration accelerates the gelation (see Table IV). It is also enhanced by an increase in the acid concentration (2). The intramolecular imidization of the polymers (initially water soluble) might have caused the gelation (10;.…”

Electrochemically induced redox polymerization of acrylamide

“…This spectra resemble the spectrum of polyacrylamide reported by earlier workers. [37][38][39] Polyacrylamide was obtained both thermally as well as electrochemically by anodic polymerization. Because same polymer structure was obtained from both the anode and cathode compartments, this supposed that the polymerization goes through the same mechanism and agrees with literature findings.…”