Photopolymerization of Methyl Methacrylate with Methyl Viologen-Na2S2O4-CCl4 in Aqueous-Organic, Two-Phase System

Abstract

ABSTRACT:The photopolymerization of methylmethacrylate (MMA) with methyl viologen (MV 2 +)-Na2 S20 4-CC14 initiator was studied in aqueous-organic two-phase system. The initial rate (Rp) of photopolymerization was proportional to the square root of fed quantity of initiator components, MV2+, Na2 S20 4 , and CC14 , respectively. Rp, however, decreased when MV2+ or CC14 was fed beyond a certain value. RP also gradually decreased in the presence of a large excess of CCl4 . A cyclic phase-transfer initiation system has been proposed for this photopolymerization on the basis of MV+ · cation radical disproportionation.

Radical Polymerization of n-BMA Using a Di-Site Phase Transfer Catalyst

“…(1)(2)(3)(4)(5)(6) refer to the organic and aqueous phase, k i, k p and k t all refer to rate of initiation, propagation and termination, respectively, and Q refers to the phase transfer catalyst. By applying the general principles of free radical polymerization and steady state hypothesis to the radical species, the rate law for this mechanism, which satisfactorily explains the above experimental observations, was derived as follows:…”

“…Even though addition of a solvent that is both aqueous-and organic-like (eg. ethanol which derives the hydrophilic nature from its hydroxyl group and lipophilic nature from the ethyl group) can make the reactants accessible, rate acceleration is minimal due to the excessive solvation of the nucleophile [5,6].…”

Temperature-sensitive photochemical aromatic substitution on 4-nitroanisole

“…There have not been many attempts to combine PTC with photochemistry. [14][15][16][17][18][19] Furthermore, this work is a part of our program on photochemistry in the microwave field, [20][21][22][23] in which a simultaneous effect of both ultraviolet and microwave irradiation on chemical reactivity 24 is investigated. MW activation often increases the efficiency of many chemical processes, which is also one of the principal tasks of green chemistry.…”

Phase-Transfer Polymerization of Methyl Methacrylate with Tetrabutylammonium Chloride–Na2S2O4-CCl4 in an Aqueous-Organic Two-Phase System

“…3 In most cases, peroxydisulfate was used as a water-soluble initiator with a phase-transfer catalyst such as crown ethers or quaternary ammonium salts. During the course of our investigation on aqueous-organic two-phase polymerization 4 we found that the addition of tetrabutylammonium chloride (TBACl) as a phase-transfer catalyst to Na 2 S 2 0cCC1 4 initiator system induced radical polymerization of methyl methacrylate (MMA) under mild condition. On the basis of kinetic studies an initiation mechanism is suggested for the polymerization of MMA with TBACl-Na2 S20cCC14 in aqueous-organic two-phase system.…”