The effect of different variables (precursor reagents, temperature, irradiation time, microwave radiation power, and additives addition) on the final morphology of nano-ZnO obtained through the microwave assisted technique has been investigated. The characterization of the samples has been carried out by field emission scanning electron microscopy (FE-SEM) in transmission mode, infrared (FTIR), UV-Vis spectroscopy, and powder X-ray diffraction (XRD). The results showed that all the above-mentioned variables influenced to some extent the shape and/or size of the synthetized nanoparticles. In particular, the addition of an anionic surfactant (sodium di-2-ethylhexyl-sulfosuccinate (AOT)) to the reaction mixture allowed the synthesis of smaller hexagonal prismatic particles (100 nm), which show a significant increase in UV absorption.

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The decomposition rate constant (kd) of diethyl ketone triperoxide (DEKTP, 3,3,6,6,9,9‐hexaethyl‐1,2,4,5,7,8‐hexaoxacyclononane) in methyl methacrylate (MMA) was determined by the kinetic study of its thermal decomposition at temperatures from 110 to 140°C. The calculated kd for DEKTP in MMA was 2.4 times lower (at 130°C) compared with that previously determined and reported in styrene (St). Density functional theory (DFT) calculations demonstrated that the decomposition of DEKTP molecule in MMA required higher interaction energy than in St, thus explaining its lower kd value. Bulk polymerization kinetics of MMA using DEKTP as the initiator revealed the presence of an induction period, in contrast with St polymerization, providing clear evidence of the solvation state influence at early polymerization stages. This work provides mechanistic insights into the interactions among the multi‐functional cyclic peroxide DEKTP and vinyl monomers; St and MMA, and their influence on the polymerization kinetics. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42905.

The thermolysis of diethylketone cyclic triperoxide (3,3,6,6,9,9-hexaethyl-1,2,4,5,7,8-hexaoxacyclononane, DEKTP) was studied in different polar solvents (ethanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-2-propanol, and acetonitrile). The rate constant values (kd) are higher for reactions performed in secondary alcohols probably because of the possibility to form a cyclic adduct with the participation of the hydrogen atom bonded to the secondary carbon. The kinetic parameters were correlated with the physicochemical properties of the selected solvents. The products of the DEKTP thermal decomposition in different polar solvents support a radical-based decomposition mechanism.

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