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Na +
Na +
-
-
Na +
-
-
-
-
Na +
-
“bottle brush” PSS
(low MW case)
Na +
+
-
-
+
+
+
- - -
-
-
+
single strand from
corona
-
+
-
+
-
-
+
+ +
micelle
core
Na +
Na +
-
-
-
Na +
-
Na +
-
-
-
-
+
“loops and trains” PSS
(high MW case)
+
+
+
Fig. 11 Structure of co-assemblies resulting from the interactions between PS- b -P2VPH + mi-
celles and PSSNa of low and high molecular weights. Reprinted from [ 65 ] with permission from
the American Chemical Society
macromolecular co-assemblies was revealed. Talingting et al. suggested that some
of the PSS − chains were strongly associated with P2VPH + blocks while some of
them were not, thereby forming “loop and train” structures. For the longer PSS −
chains, the authors expected parts of the PSS − chains to be extended outside the
micellar coronas, providing additional overcompensation, whereas they proposed
the formation of “bottle-brush” structures for the shorter PSS − chains (Fig. 11 ) . As
also indicated by the authors, the formation of the massively overcharged complex
species could be a result of the “kinetic trapping” of PSS − chains in the coronas of
PS- b -P2VPH + micelles due to the strong binding of oppositely charged polymeric
components and, therefore, to the rather low rate of macromolecular rearrangements
that would lead to alignment of the PSS − chains along P2VPH + blocks, thereby
providing a charge balance for the formed complex species.
Further investigations in this field, specifically studies on the interaction of
poly(isobutylene)- block -poly(sodium methacrylate) (PIB- b -PMANa) micelles with
P4VPQ in alkaline media by Pergushov et al. [ 66 - 68 ] and Burkhardt et al. [ 69 ] ,
demonstrated for the first time the possibility of formation of novel macromolec-
ular co-assemblies in which the original diblock copolymer micelles apparently
play a lyophilizing role. Such micelles act as the HPE and provide solubility
(stability against aggregation and precipitation) of the whole complex in aqueous
media. To explain the experimental observations, the onion-like (core-shell-corona)
structural model of these IPECs was proposed. In contrast to the previous paper by
Talingting et al. [ 65 ], the PIB- b -PMANa micelles were used in excess compared to
P4VPQ so that the molar concentration of their ionic groups in the aqueous mixtures
of the oppositely charged polymeric components exceeded that of the linear PE.
The addition of P4VPQ into an aqueous solution of the PIB- b -PMANa micelles
was found to induce macroscopic phase separation of the aqueous mixtures of
oppositely charged polymeric components only if the ratio between the molar con-
centrations of their ionic groups Z
N + ] / [
COO − ] ,
(
Z
=[
Z
<
1
)
exceeded the certain
threshold value of Z M (Fig. 12 ) . At Z
<
Z M , the aqueous mixtures of the PIB- b -
 
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