Polymerization under a magnetic field. VI. Triplet dye-sensitized photopolymerization of acrylamide and methyl methacrylate

Abstract

Methylene blue sensitized photopolymerization of acrylamide (AM) and methyl methacrylate (MMA) using triethanolamine or the sodium salt of EDTA as a reducing agent has been investigated under the influence of a magnetic field (0–7.3 kG). There was no effect of the magnetic field (MF) on the polymerization of AM and MMA in aqueous medium. However, in the water–methanol mixture (1 : 1) the yield of polymer decreases and the molecular weight increases in both cases under MF. This has been explained on the basis of the triplet mechanism. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1509–1513, 1998

Magnetic field effects on the free radical solution polymerization of acrylamide

“…In particular, the solution photopolymerization of acrylamide (AM) in binary mixtures of water/ethylene glycol (EG) has shown increased R p [8]. Similar results were obtained for the photopolymerization of AM in water and water/methanol mixtures [6]. Though for the latter solvent mixture, lower polymer yield and higher molar mass were reported under MF.…”

Kinetic control of aqueous polymerization using radicals generated in different spin states

“…Increase of Rp, polymer yield, molar mass, syndiotacticity, crystallinity, and thermal stability of resulting polymers [4] MMA, ST AIBN Bulk No effect [4] MMA MB H 2 O-MeOH mixtures Decrease of the polymer yield and increase of the molar mass polymers [5] MMA MB Aqueous solution No effect [5] MMA BP, AMP, APA, AHC Aqueous solution Increase of the initiator efficiency and decrease of the monomer exponent and molar mass [6] AC, MMA, AM BP, AMP, APA, AHC Several solvents Increase of the initiator efficiency and thermal stability of polymers [7] MMA, EMA, BMA AIBN Bulk Increase of molar mass and thermal stability of products [ Increase of Rp of all monomers in homo and copolymerizations. Increase of molar mass of polyAA.…”

“…Here ∆χ M is the change of the magnetic susceptibility during the reaction of one molar unit. Therefore, according to Equations (4) and (5), the higher the MF intensities and the lower the temperatures are, the more important the MF effects on f and k t will be.…”

“…Processes 2017, 5,15 www.mdpi.com/journal/processes magnet in order to determine the calibration curve shown in Figure 3. The MF was adjusted by setting the distance between the reactor and the core of the magnet according to the calibration curve.…”

Radical Homo‐ and Copolymerization of Acrylamide and Ionic Monomers in Weak Magnetic Field

“…MF effects have previously been observed for the radical homopolymerization of styrene, [2][3][4][5][6][7][8][9] methyl methacrylate, [10][11][12][13][14][15] and acrylamide. [16][17][18] In general, MF was found to increase the monomer consumption rate (Rp), and sometimes the molar masses of resulting polymers. A MF-induced increase of the efficiency of photoinitiators (F) and induced decrease of the rate of termination reactions have been proposed as mechanistic explanation.…”