AbstractPotassium persulfate modes of thermal decomposition and reactions with ethyl acrylate in aqueous solution at 50°C in nitrogen atmosphere have been investigated. It has been found that the rate of persulfate decomposition may be expressed as −d(S2O 82−)/dt∝ (S2O 82−)1.00 ± 0.06× (M)0.92±0.05while the steady state rate of polymerization (Rp) is given byRp∝ (S2O 82−)0.50 ± 0.50× (M)1.00 ± 0.06in the concentration ranges of the persulfate, 10−3−10−2(m/L), and monomer (M), 4.62−23.10 × 10−2(m/L), i.e., within its solubility range. In the absence of monomer, the rate of persulfate decomposition was slow and first order in persulfate at the early stages of the reaction when the pH of the solution was above 3.0. The separating polymer phase was a stable colloid at low electrolyte concentrations even in the absence of micelle generators. It has been shown that the oxidation of water soluble monomeric and oligomeric radicals by the S2O 82−ions in the aqueous phase, viz.,documentclass{article}pagestyle{empty}begin{document}$ {rm M}_j^ cdot + {rm S}_2 {rm O}_8^{2 - } to {rm M}_j - {rm O} - {rm SO}_3^ - + {rm SO}_4^{ cdot - } $end{document}is not kinetically significant in this system. It has been found that the reactiondocumentclass{article}pagestyle{empty}begin{document}$ {rm M} + {rm S}_2 {rm O}_8^{2 - } rightarrow{k}{rm M} - {rm O} - {rm SO}_3^ - + {rm SO}_4^{ cdot - } $end{document}would also lead to chain initiation at the outset of the polymerization reaction.khas been estimated as 5.41 × 10−5(L/m/s) at 50°C. Takingkpas 103(L/m/s),kthas been estimated as 0.168 × 106(L/m/s). The partition confficient (β) of the monomer between the polymer phase and the aqueous phase was found to be 16 ± 2, at 50°C. The rate constant for persulfate ion disso
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