Surface‐active metal‐coordinated oligoperoxidic radical initiators. I. The interrelation between the microstructure of ditertiary oligoperoxides and their ability to form stable metal complexes

Carbon‐chain heterofunctional oligoperoxides (HFOs) with ditertiary peroxidic, carboxy, or hydroxy groups formed stable coordinated complexes through their interaction with transition‐metal salts in organic solutions. The oligomeric metal complexes (OMCs) were separated from the reaction mixture and investigated through elemental analysis, voltammetry, and atom‐adsorption, IR, and UV spectroscopy. From these investigations and the calculated values of the mole fraction and formation constants of the stable complexes of the copper cations and HFOs, the probable cooperative mechanism of the complex formation by such oligomers was suggested. The existence of two levels of HFO molecule ordering, namely HFO microstructure and the structure of the hydrogen‐bonded complexes formed by HFOs, explained the cooperative mechanism and some characteristics of the OMC formation. The mole fraction and formation constants of the OMCs were interrelated with the disposition of the complex‐forming groups in the chain of HFOs. From the experimental data, it can be concluded that the complex‐forming groups of the HFOs possessed different reactivities both in the complex formation with metal cations and in the reactions involving the resulting OMCs. The shift in the half‐wave potential of the  O:O bond reduction during the transition from the HFO to a mixture of HFO and Cu²⁺ and to OMC indicated an increase in its reactivity. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 516–527, 2000