Chemistry Reference
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Figure 3. UV spectra measured from photosensitive polymer films exposed to an unpolarized UV
light (260-380 nm wavelength) with varying exposure dose: (a), 6F-HAB-CI; (b), 6F-HAB-
ETCOU.
(=
λ
max
). This UV absorption originates from the photosensitive cinnamate side
group in the polymer. The absorption peak intensity at
λ
max
= 278 nm drops dras-
tically with increasing exposure dose up to 7.5 J/cm
2
and then stays almost con-
stant with further increasing exposure dose. On the other hand, 6F-HAB-ETCOU
polymer reveals a maximum absorption at 306 nm, which results from the photo-
reaction of coumarin side group. This peak is relatively weaker in intensity than
that of 6F-HAB-CI polymer. The intensity of the absorption peak at
λ
max
= 306
nm drops gradually with increasing exposure dose and then levels off at 7.5 J/cm
2
.
These results suggest that the cinnamate side group has a relatively higher
extinction coefficient at
λ
max
= 278 nm than that of the coumarin side group at
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