consider and update the main achievements regarding the preparation and investigation of such advanced IPECs, which are also reported in a recent review [43].
The increasing interest to IPECs based on polyionic species of nonlinear topology
is mainly due to the possibility of using them as a basis for building (optionally, to
template) easily available and multifunctional polymeric architectures, which are of
high potential for applications in rapidly developing nanotechnologies connected with
such important areas as nonviral gene delivery, targeted/prolonged drug delivery,
preparation of nanosized catalytic systems, etc.
3.1 IPECs Based on Star-Shaped (Co)Polymers
Star-shaped polymers (also referred to as polymer stars or star polymers) represent
isotropic centrosymmetric macromolecules, each containing a single branching
point in a center of a macromolecule (Fig. 6a). They can be prepared via a
“core-first” or an “arm-first” approaches. The branching point represents a small
core remaining from an oligofunctional initiator (“core-first” approach), which is
used to polymerize arms, or from a multifunctional cross-linker (“arm-first”
approach), which is used to cross-link arms. The core determines the number of
arms while the arms determine the overall size of the synthesized polymer star.
Macromolecules of star-shaped polymers are characterized by a well-defined size
(in the nanometer range) and a spherical morphology, both resulting from their
inherent structuring.
Successful synthesis of well-defined star-shaped ionic (co)polymers [44] is a
prerequisite for preparation of their IPECs. In connection with this, we consider
papers [45, 46] that report on water-soluble IPECs with a star-shaped polyion,
e.g., poly(sodium acrylate) (PANa) stars, acting as HPE. Water-soluble IPECs are
formed when charged groups of the star-shaped HPE are in certain excess compared
to charged groups of its polymeric counterpart (P4VPQ). Otherwise, macroscopic
a
b
c
Fig. 6 A polyelectrolyte star (a), a micelle with a polyelectrolyte corona (b), and a cylindrical
polyelectrolyte brush (c)
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The increasing interest to IPECs based on polyionic species of nonlinear topology
is mainly due to the possibility of using them as a basis for building (optionally, to
template) easily available and multifunctional polymeric architectures, which are of
high potential for applications in rapidly developing nanotechnologies connected with
such important areas as nonviral gene delivery, targeted/prolonged drug delivery,
preparation of nanosized catalytic systems, etc.
3.1 IPECs Based on Star-Shaped (Co)Polymers
Star-shaped polymers (also referred to as polymer stars or star polymers) represent
isotropic centrosymmetric macromolecules, each containing a single branching
point in a center of a macromolecule (Fig. 6a). They can be prepared via a
“core-first” or an “arm-first” approaches. The branching point represents a small
core remaining from an oligofunctional initiator (“core-first” approach), which is
used to polymerize arms, or from a multifunctional cross-linker (“arm-first”
approach), which is used to cross-link arms. The core determines the number of
arms while the arms determine the overall size of the synthesized polymer star.
Macromolecules of star-shaped polymers are characterized by a well-defined size
(in the nanometer range) and a spherical morphology, both resulting from their
inherent structuring.
Successful synthesis of well-defined star-shaped ionic (co)polymers [44] is a
prerequisite for preparation of their IPECs. In connection with this, we consider
papers [45, 46] that report on water-soluble IPECs with a star-shaped polyion,
e.g., poly(sodium acrylate) (PANa) stars, acting as HPE. Water-soluble IPECs are
formed when charged groups of the star-shaped HPE are in certain excess compared
to charged groups of its polymeric counterpart (P4VPQ). Otherwise, macroscopic
a
b
c
Fig. 6 A polyelectrolyte star (a), a micelle with a polyelectrolyte corona (b), and a cylindrical
polyelectrolyte brush (c)
188
D.V. Pergushov et al.