Indolinic nitroxides derived from 2,2-diphenyl-3-phenylimino-2,3-dihydroindol-1-yloxyl (DPAIO) nitroxide were designed to improve the bulk polymerization of methacrylate derivatives. The corresponding alkoxyamines were prepared by reacting alkyl halide and nitroxide in the presence of tin hydride and PbO₂. The replacement of one phenyl ring at the C-2 position on the nitroxide by either a neopentyl or an isopropyl group led to compounds with faster decomposition kinetics and better selectivity for the C–ON bond homolysis. The alkoxyamines derived from these two nitroxides were used to control the polymerization of methyl methacrylate and were also tested for the polymerization of styrene as a model for mono-substituted monomers. The shift of the molar mass distribution during the NMP of styrene showed for the first time that pure homopolymerization of styrene and methacrylate derivatives could be controlled by the same nitroxide, thus opening the way to a universal nitroxide for NMP.

Polymerization reactions with organic electron donors (OED) as initiators are presented herein. The metal‐free polymerization of various activated alkene and cyclic ester monomers was performed in short reaction times, under mild conditions, with small amounts of organic reducing agents, and without the need for co‐initiators or activation by photochemical, electrochemical, or other methods. Hence, OED initiators enabled the development of an efficient, rapid, room‐temperature process that meets the technical standards expected for industrial processes, such as energy savings, cost‐effectiveness and safety. Mechanistic investigations support an electron‐transfer initiation pathway that leads to the reduction of the monomer.

The current study reports the complete kinetic analysis of acetoacetoxyethyl methacrylate (AAEMA). The temperature dependent propagation rate coefficient, k_p, was accessed by pulsed laser polymerization-size exclusion chromatography (PLP-SEC), affording the following Arrhenius parameters: A = 2.13 × 10⁶ L mol⁻¹ s⁻¹ and E_a = 19.69 kJ mol⁻¹. For the SEC-analysis, the Mark–Houwink–Kuhn–Sakurada (MHKS) parameters of the corresponding polymer were determined (K = 0.0250 mL g⁻¹; α = 0.547) via multiple detection SEC. Furthermore, reactivity ratios for the copolymerization with methyl methacrylate (MMA) at 75 °C in ethyl 3-ethoxypropionate (EEP) were obtained by the Meyer–Lowry method (r_MMA = 0.89; r_AAEMA = 0.98), supported by a detailed kinetic simulation using the PREDICI simulation package. In addition, copolymerization was carried out at ambient temperature with a bicomponent dibenzoyl peroxide (BPO)/dihydroxyethyl-p-toluidine (DHEPT) initiator system, demonstrating a strong increase of the rate of copolymerization with increasing AAEMA content (i.e. 40% decrease of the gel time by adding 10 mol% of AAEMA).