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Sodium formaldehyde sulfoxylate (SFS) is not used as an
initiator or in redox initiation polymerization but as a
agent to regenerate metal oxidants from a higher valence to
lower one. However, the reactions of (SFS) with various
monomers including acrylates, methacrylates, styrene and
vinyl acetate were studied in this text. The reaction products
formed depended on the molecular structure of the monomers
and acidity of the reaction solution. Among these monomers
studied, the acrylates with polarity (e) values higher than
0.55 produced diacrylate sulfones under a neutral
condition. The other monomers or reaction condition did
not result in a dimer product. The obtained diacrylate
sulfones were characterized using elemental analysis, mass
spectrometry, IR spectra, normal 1H- and 13C- NMR, CHn (n=1, 2
and 3) subspectra by Distortionless Enchancement by
Polarization Transfer, as well as the 1H-13C 2D-NMR spectra
by the Correlated Spectroscopy and Heteronuclear Multiple
Bonding Correlation methods. A possible reaction
mechanism for the formation of dimers was suggested. The
morphology and thermal property of these diacrylate
sulfones were determined.On the other hand, the SFS can
react with sodium lauryl sulfate (SLS) surfactant to produce
radicals, which were measured by electron paramagnetic
resonance (EPR), to initiate emulsion polymerization of vinyl
monomers. As the acrylate monomer were initiated by SFS/
SLS pair, the polymerization rate and conversion would be
seriously influenced by the dimerization of the SFS with
acrylate monomers in aqueous solution. The more hydrophilic
of acrylate monomer, the lower conversion of
polymerization. Thus, the polymerization rate (Rp) of n-butyl
acrylate were proportion -0.
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