M. Ejaz et al., Controlled grafting of a well-defined glycopolymer on a solid surface by surface-initiated atom transfer radical polymerization, MACROMOLEC, 33(8), 2000, pp. 2870-2874
The atom transfer radical polymerization (ATRP) technique using the copper
(Cu)/4,4'-di-n-heptyl-2,2'-bipyridine (dHbipy) complexes was applied to the
graft polymerization of a sugar-carrying methacrylate, 3-O-methacryloyl-1,
2:5,6-di-0-isopropylidene-D-glucofuranose (MAIpGlc), on the substrate on wh
ich the monolayer of the initiator, 2-(4-chlorosulfonylphenyl)ethyltrimetho
xsilane was immobilized by the Langmuir-Blodgett technique. Ellipsometric a
nd atomic force microscopic analyses confirmed that the polymerization carr
ied out in the presence of the (sacrificing) free initiator, p-toluenesulfo
nyl chloride, afforded a homogeneous graft layer on the substrate. The thic
kness d of the graft layer in a dry state increased with reaction time and
in proportion to the number-average molecular weight M-n of the (low-polydi
spersity) free polymers produced in the solution. This proportional relatio
nship between d and M-n strongly suggests a controlled growth of the graft
chains, as well as of the free chains, with the graft density kept constant
. Grazing-angle reflection-absorption FTIR studies revealed that the isopro
pylidenyl groups of the poly(MAIpGlc) grafts were quantitatively converted
to the hydroxyl groups by treatment with formic acid, thus producing the fi
rst solid surface densely grafted with a well-defined glucose-carrying poly
mer.