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10
5
10
4
3-C
12
10
3
Water
10
2
10
1
1-C
12
PA
10
0
10
-5
10
-4
10
-3
10
-2
10
-1
Surfactant concentration (mol
L
-1
)
The change in viscosity of a 1% aqueous solution of precursor (PAA) and modified polymers (1% and
3% C
12
) with CTAB surfactant concentration. The hatch symbol shows the limit of the phase
separation. The viscosity measured at shear rates between 0.1 and 1 s
−
1
was reported to be Newtonian.
Adapted with permission from Magny et al.(
1994
) © 1994 American Chemical Society.
Figure 6.11
Interchain
mixed
aggregate
Surfactant
Intrachain
basic
aggregate
Schematic representation of surfactant
-
HM water-soluble polymer interactions: inter-chain mixed
aggregates at low surfactant concentration are progressively converted into intra-chain mixed
aggregates at high surfactant concentration. Adapted with permission from Magny et al.(
1994
)©
1994 American Chemical Society.
Figure 6.12
surfactants, and alkyl groups belonging to two distinct polymer chains, induce
'
cross-
linking
between the chains, which increases viscosity well above the contribution shown
by the alkyl modi
'
cation itself (although there is a small increase in the viscosity of
these modi
ed polymer as compared to the unmodi
ed ones). At higher surfactant
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