Chemistry Reference
In-Depth Information
d
n
1
r
3
n
g
|
7
Scheme 5.7
Examples of gelators used as templates for polymer imprinting.
3
.
channels.
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In parallel, Nolte and coworkers reported the transcription of
the fibrillar nanostructures formed in methacrylate mixtures by n-octyl gluco-
namides (28) after polymerisation of the solvent (Scheme 5.7). Nanopores
could be observed, however, the imprinting process failed in the transcription
of the supramolecular chirality observed in the original gel probably due to the
shrinking of the methacrylate gel during polymerisation.
38
More recently, Me
ยด
sini and coworkers have succeeded in the transcription of
supramolecular chirality from helical tapes formed by 3,5-bis(5-hexyl-
carbamoylpentyloxy) benzoic acid decyl ester (29) in ethylene glycoldiacrylate
into helical pores after photopolymerisation and extraction of the template
with CH
2
Cl
2
(Scheme 5.7).
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The same helical tapes, closed into nanotubes,
have been used by this group for the preparation of imprinted nanotubes with
application as catalytic materials.
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In most of these examples the gelator is washed-out from the material after
imprinting because the transcription of the nanostructured shape is the main
objective. However, it may also be interesting to keep the supramolecular
nanostructures embedded within the polymer especially when the gelator in-
corporates a useful functionality. For example, Moffat and Smith have re-
ported the preparation of fluorescent ''two-faced'' polymer wafers by using gels
formed by pyrene-based compound 30 as templates for styrene/divinylbenzene
polymerisation. They show that during the reaction some gelator molecules
migrate towards one of the faces of the polymer leading to a material with
different luminescent properties in both sides of the wafer.
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