Résumé
Copolymerization of an excess of methyl methacrylate (MMA) relative to 2-hydroxyethyl methacrylate (HEMA) was carried out in toluene at 80°C according to both conventional and controlled Ni-mediated radical polymerizations. Reactivity ratios were derived from the copolymerization kinetics using the Jaacks method for MMA and integrated conversion equation for HEMA (rMMA = 0.62 ± 0.04; rHEMA = 2.03 ± 0.74). Poly(ethylene glycol) α-methyl ether, ω-methacrylate (PEGMA, Mn = 475 g mol-1) was substituted for HEMA in the copolymerization experiments and reactivity ratios were also determined (r MMA = 0.75 ± 0.07; rPEGMA ∼ 1.33). Both the functionalized comonomers were consumed more rapidly than MMA indicating the preferred formation of heterogeneous bottle-brush copolymer structures with bristles constituted by the hydrophilic (macro)monomers. Reactivity ratios for nickel-mediated living radical polymerization were comparable with those obtained by conventional free radical copolymerization. Interactions between functional monomers and the catalyst (NiBr2(PPh3) 2) were observed by 1H NMR spectroscopy.
langue originale | Anglais |
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Pages (de - à) | 2255-2263 |
Nombre de pages | 9 |
journal | European Polymer Journal |
Volume | 41 |
Numéro de publication | 10 |
Les DOIs | |
Etat de la publication | Publié - 1 oct. 2005 |
Modification externe | Oui |