Preparation of functionalized alkoxyamine initiator and its use

#The invention relates to a process for the preparation of functionalized alkoxyamine initiators and to their use in radical polymerization.

#A one-pot process for the preparation of functional alkoxyamines of the general formula (I),

#is disclosed. The process entails (1) reacting an oxidizing agent with a sterically hindered secondary amine to produce an aqueous phase and a nitroxy radical (2) removing the aqueous phase and adding to the nitroxy radical one or more vinyl monomer(s) conforming to a formula and a system which produces free radicals. Also disclosed is a process of polymerizing monomers using the functional alkoxyamine.

#The following Examples illustrate the invention in more detail.

#The molecular weight was determined by gel permeation chromatography (GPC), equipped with a Shodex RI 74 differential refractometer. A flow rate of 1 ml/min was used and samples were prepared in THF. Polystyrene standards were used for calibration.

#In a 500 ml four-necked round bottom flask equipped with a mechanical stirrer, a reflux, a thermometer, a funnel and a septum are added 40 g of water, 10 g K2CO3 (99%; 7.24·10−2 mol), 5 g 2,2,6,6-tetramethylpiperidine (99%; 3.53·10−2 mol) and 50 g toluene. Then, a solution of 21,702 g of Oxone® (Monopersulfate, DuPont Specialty Chemicals, USA) (3.53·10−2 mol) in 100 g water is slowly added to the 500 ml flask while stirring vigorously (with a slightly exothermic reaction) and the flask is placed in a water bath at room temperature. After the addition, the reaction medium is stirred at room temperature for 30 minutes, and the organic phase becomes progressively red due to the formation of 2,2,6,6-tetramethylpiperidine-1-oxide (TEMPO). Then, the reaction medium is heated at 40° C. for further 30 minutes.