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e
lg
4.8
4.6
4.4
4.2
4.0
3.8
4
2
3.6
3
1
3.4
l
HM
200 220 240 260 280 300 320 340 360
Figure 2.30. U-v spectrum (acetonitrile) 1- CA-film, containing 5 % of compound (V) before
irradiation; 2 - the same sample after irradiation; 3 - CA-film, containing 2% of compound (V) before,
4 - and after irradiation.
Table 20. Kinetic parameters of polymerization in the presence of
carbazolsulphonamides
W
st
int
·10
4
, mole/l·s
W
gel
int
·10
4
, mole/l·s
№
F
st
F
gel
XXIII
5,0
0,64
41,3
0,83
XXVII
3,8
1,28
23,0
2,32
XXX
4,7
0,77
34,7
1,32
XXV
6,0
0,28
42,2
0,79
XXVIII
3,5
1,49
32,8
1,36
without inhibitor
6,9
62,0
Measuring U-v - spectrum displayed, that modifier concentration of 2% to the mass of a
fiber change spectrum considerably. It is necessary to note, that after irradiation the spectrum
looks differently: absorption bands change to reduction. Possibly, these changes are caused by
absorption of CDA decomposition products CDA, which, in its turn, decelerates further
polymer decomposition.
As it is established in [183], aromatic sulphuryl amides can exist in solid state in the form
of open or cyclic dimers owing to intermolecular hydrogen bonds.
There is an opinion, that sulphuryl amide grouping can have anti-configuration, that is,
either О-S-N-Н atoms are lying in the same plane or oxygen and nitrogen atoms oppose each
other [184].Thus, as carbazole and indan derivatives include sulphuryl amide grouping, it is
possible that light stabilizing effect of additions is due to hydrogen bonds, as it happens in о-
hydroxybenzophenone [185]. The light stabilizing effect of the latter is determined by rapid
and convertible phototransition of a proton participating in intermolecular hydrogen bond
formation.
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