Thermal decomposition of 3,3,6,6,9,9-hexaethyl-1,2,4,5,7,8-hexaoxacyclononane in solution and its use in methyl methacrylate polymerization

Solution Polymerization of Methyl Methacrylate in an Ionic Liquid Employing Cyclic Multifunctional Initiators

“…As it was previously reported, the thermal decomposition of this kind of multifunctional initiators is strongly dependent of the solvent used . Moreover, when monomers such as MMA and styrene were employed as the reaction media, there was clear evidence of a strong dependence of the monomer nature on the initiators decomposition. In this sense, and taking the pinacolone diperoxide (PDP) at 140°C as an example, its decomposition rate constants ( k d ) was 27.4 × 10 −5 s −1 in benzene, 43.4 × 10 −5 s −1 in acetic acid, 30.5 × 10 −5 s −1 in acetonitrile, 23.2 × 10 −5 s −1 in n ‐octane, 75.8 × 10 −5 s −1 in 2‐methoxymethanol and 29.6 × 10 −5 s −1 in toluene .…”

Effect of ionic liquid on the thermal decomposition of cyclic organic peroxides

“…The activation parameters determined by the Eyring equation, for both peroxides (Table 2 and 3 (Barreto and Eyler, 2011), b (Barreto et al, 2014), c (Eyler et al, 1994). (Cafferata et al, 1990), b (Cafferata et al, 1991) In previous studies Cañizo, 2006), it has been found that k d values obtained from kinetic determinations in solvents with different physicochemical properties are sensitive to solvent polarity and are well correlated with the Dimroth-Reichardt solvent polarity parameter (E T (30)) (Reichardt, 1965).…”

“…Among several cyclic peroxides, two of them, the 3,6-diterbutyl-3,6-dimethyl-1,2,4,5-tetraoxacyclohexane (PDP, pinacolone diperoxide) and the 3, 3,6,6,9,9-1,2,4,5,7,8-hexaethyl hexaoxacyclononane (DEKTP, diethylketone triperoxide) (Scheme 1), have been extensively studied not only from the kinetic approach but also because they have demonstrated a good performance in polymerization processes (Cerna et al, 2002;Cañizo, 2006;Barreto and Eyler, 2011).…”

“…Moreover, it was found that these cyclic peroxides thermally decomposed in solution by the homolytic cleavage of one of the O-O bonds generating a biradical intermediate (Scheme 2) which, in later stages, can be decompose following different routes Cañizo, 2006). Because of radicals generation through PDP and DEKTP decomposition, these peroxides were efficiently used as multifunctional initiators in the radical polymerization of styrene and methyl methacrylate monomers (Cerna et al, 2002;Cañizo, 2006; Barreto and Eyler, 2011).…”

Cyclic organic peroxides thermal decomposition in the presence of CuFe2O4 magnetic nanoparticles

“…In previous works, it was demonstrated that different peroxides have application as polyfunctional initiators in styrene and methylmethacrylate polymerization [8][9][10]. For example, the use of diethylketone triperoxide allowed obtaining high monomer conversions in short times (100% for methylmethacrylate [10] and 30% for styrene [8] in 50 min at 130 • C) with an increase in final polymeric product molecular weights, compared with typical monofunctional initiators. Di-and tri-acetone cyclic peroxides are low cost and easy to synthesize; nevertheless, it has been demonstrated that their thermal stabilities in solution are higher than those showed by diethylketone triperoxide or pinacolone diperoxide [11,12].…”