A study on acrylamide polymerization by anodic contact glow‐discharge electrolysis: A novel tool

Abstract

Contact glow-discharge electrolysis (CGDE) is an unconventional electrolytic phenomenon in which a plasma is sustained by a direct current (dc) glow-discharge between an electrode and the liquid electrolyte around it. A remarkable feature of CGDE is highly nonfaradaic chemical effects at the glow-discharge electrode. During anodic CGDE of an aqueous electrolyte, non-Faradaic yields originate mainly from reactions triggered by H • and OH • radicals generated in high local concentrations near the anodic plasma/liquid electrolyte interface during the process. The radical-generating potentiality of anodic CGDE was explored for the polymerization of acrylamide in aqueous media. The percentage of monomer conversion, rate of polymerization, charge efficiency, and viscometric average molar mass of the polymers produced were measured as functions of the quantities of electricity passed. The charge efficiency of the polymerization of acrylamide by anodic CGDE was at least 1 order of magnitude higher than that of ordinary electrochemically initiated polymerization.

Synthesis and Characterization of Montmorillonite-Graft-Acrylic Acid Superabsorbent by Using Glow-Discharge Electrolysis Plasma

“…Thereby, various techniques are appearing for improving the properties of superabsorbents. Roughly, it may be classified into two categories, i.e., initiated polymerization by using chemicals [8,11] and by physical techniques, for example, photo-polymerization [12], irradiation-polymerization [13], plasma-polymerization [14] and so on. Various physical methods have little pollution to environment, in which the GDEP has more advantages such as lower cost in set-up and easy operation in polymerization.…”

Synthesis and Characterization of Polymethylmethacrylate by Using Glow Discharge Electrolysis Plasma

“…In other words, GDE could be considered as rich sources of free radicals in aqueous solution, and applied to induce some unusual chemical changes in the solution. In 2001, Sengupta reported the polymerization of acrylamide initiated by GDE [18]. We have also synthesized the superabsorbent composite with excellent characteristics by using glow discharge electrolysis plasma [19].…”

Scavenging Effects of Aliphatic Alcohols and Acetone on H• Radicals in Anodic Contact Glow Discharge Electrolysis: Determination of the Primary Yield of H• Radicals

“…The radicals initiate several reactions to give rise to considerable yields of H 2 , H 2 O 2 and O 2 E there by a radiolytic mechanism [6,7]. The potentiality of anodic CGDE as a tool for generating radicals in high local concentrations has been amply demonstrated by examples of its applications in the synthesis of hydrazine from ammonia [1,10], oxalic acid from formic acid [11], polyacrylamide from acrylamide [12,13], glycine and a-alanine from ammonia and carboxylic acids [14] and in the degradation of polymers [15], dipeptides [16] and of organic contaminants in waste waters [17][18][19][20][21]. Obviously, it needs developing a method for determining conveniently the primary yield of H • /OH • radicals in the liquid-phase reaction zone of anodic CGDE.…”