Functionalization of poly(<Emphasis Type="Italic">N</Emphasis>-ethylmethacrylamide) thermosensitive particles by phenylboronic acid

The synthesis of poly(N-ethylmethacrylamide) (NEMAM) thermosensitive particles functionalized with phenylboronic acid (PhBA) groups has been performed by emulsion/precipitation polymerization of NEMAM in water at 90 °C, using ethylene glycol dimethacrylate (EGDMA) as an hydrophobic crosslinker, phenylboronic acid methacrylamide (PhBAMA) as a functional monomer, and potassium persulfate (KPS) as an initiator. The influences of the PhBAMA concentration and mode of monomer addition (batch or shot-growth processes) have been examined both on the polymerization kinetics and on the physicochemical and colloidal properties of the final particles. Results have been discussed according to the ionogenic and hydrophobic nature of the functional monomer. We have directly and clearly provided evidence that PBA was successfully incorporated at the particle surface by using ESCA analysis, especially when using a shot-growth process, a result that was indirectly confirmed by investigating the electrophoretic mobility behavior of the various latexes as a function of pH.