Atom Transfer Radical Polymerization of methyl methacrylate using iminopyrdineiron complexes immobilized into fluorotetrasilicic mica interlayer

[出版社版]The iminopyridine iron(III) and (II) complexes were immobilized into fluorotetrasilicic mica interlayers through the intercalation of the iminopyridine ligand into the mica interlayers and simultaneous coordination of the ligand to the interlayer metal cations. The prepared catalysts were used for atom- transfer radical polymerization (ATRP) of methyl methacrylate (MMA). The Fe3+-based catalyst did not show a significant activity for the ATRP of MMA, whereas when ATRP was performed using the Fe2+-based catalyst, PMMA (poly(methyl methacrylate)) was obtained. Two peaks were observed in the GPC curve of the produced PMMA. Because polydispersity index was higher than 2, free-radical polymerization occurred simultaneously. To suppress the free-radical polymerization, we varied initiator/catalyst molar ratio. On increasing the molar ratio from 2/1 to 4/1 (favorable conditions for free-radical polymerization), PMMA with higher Mw was obtained. In contrast, by decreasing the molar ratio from 2/1 to 1/1 (favorable conditions for ATRP), PMMA with lower Mw was obtained. Those results clearly indicate that the lower Mw peak in the GPC curve corresponds to PMMA produced by ATRP