Effect of organized anionic surfactant system on the kinetics of V(V)-organic substrate-initiated polymerization of acrylonitrile

Abstract

ABSTRACT:The kinetics of polymerization of acrylonitrile (AN) initiated by a V(V)-cyclohexanone redox system in the presence of a surfactant was studied over a temperature range of 30-50ЊC in acidic medium. The anionic surfactant sodium dodecyl sulfate (SDS) enhances the rate of polymerization (R p ) as well as rate of V(V) consumption (0R v ). The cationic surfactant, cetyltrimethylammonium bromide (CTAB), decreases both R p and 0R v , while the nonionic surfactant, Triton-X-100, has no effect on the rate. The change of concentration of the surfactant, monomer, acid, and cosolvent on the rate of polymerization were examined. Both R p and 0R v are computed in the presence of different organic substrates, i.e., cyclohexanone, cyclopentanone, glycerol, and citric acid. The viscosity-average molecular weight (M V v ) of the polycrylonitrile, obtained at different [SDS], was determined using the Mark-Howink relationship. A suitable mechanistic scheme was proposed for the process. EXPERIMENTAL INTRODUCTION MaterialsReviews of the literature indicate that an appreciable amount of work has been carried out on the Acrylonitrile (Sisco Chem.) was washed with 5% NaOH and 3% o-phosphoric acid and, finally, with kinetics of aqueous vinyl polymerization by V(V) water followed by drying over CaCl 2 . It was furwith an organic substrate by various workers.

Polymerization of Acrylamideinitiated by V(v)-Cyclohexanone Redox System in Micellar Phase: A Kinetic Study

“…But, in the presence of cationic surfactant, the rates as well as the percentage of acrylamide conversion decreased considerably as compared to that in absence of surfactant. The rate of consumption of V(V), -R V was found to increase with the SDS concentration and decrease with an increase of CTAB as observed in our earlier work [19,20]. SDS also increased the rate of acrylamide polymerization using peroxodiphosphate as initiator [27].…”

“…Under our experimental conditions, the termination is more effective than the initiation, which leads to a decline in the rate at a higher concentration of V(V) [19,20]. V(V) has the capability of influencing both the initiation and the termination processes.…”

“…At a higher concentration of cyclohexanone, its solubilization in the micellar part will be more, leading to a greater number of free radicals [14][15][16][17][18][19][20][21] which enhances the rate. This can be explained on the basis of solubilization.…”

Kinetics of Vinyl Polymerization of Methyl Methacrylate Initiated by Ce(IV)‐Vanillin Redox System

“…Several reports have appeared on the mechanism and kinetics of vinyl polymerization initiated by a variety of initiators [3][4][5][6] . Ceric ion has been used in vinyl polymerization in the presence of various organic reducing agents such as alcohols 7 , acids 8 , amides 9 , amines 10 , etc.…”