ligand groups [92] (Fig. 22a) induces assembly of the cationic blocks. The formation of complex micelles in the system containing the coordination polymer
involves two simultaneous synergistic processes [80]: the formation of micelles
and polymerization of coordination supramolecules due to a sharp local increase
in the concentration of metallo-containing units. The cryo-TEM images prove
the formation of micelles with cores, which are highly contrasted by metal ions
(Fig. 22b).
The morphology of micellar IPECs is under the control of mixture stoichiometry. By direct mixing of the components at a 1:1 charge-to-charge ratio, spherical
micelles (Fig. 22) with a radius of ca. 25 nm are formed [80, 92]. Worm-like
micelles (Fig. 23) with a hydrodynamic radius of over 150 nm were found in a
mixture with excess positive charge [80, 92].
Design of advanced medicines and delivery drug systems has stimulated interest
in microcapsulation of magnetic or antibacterial NPs incorporated into polymers
[141, 142]. Fabrication of superfine catalytic or electronic devices is another
reason for development of hierarchically organized metallo-containing polymer
systems [95, 96, 143–145]. The nanostructured polymer systems give a fine tool
for control of NP growth through variation of the interface interactions [143].
Immobilization of metal NPs into polymeric matrices such as micelles [146],
microemulsions and microgels [147, 148], dendrimers [149, 150], block
co-/terpolymer self-/co-assemblies [95, 96, 143, 145, 151], and spherical polyelectrolyte brushes [152, 153] provides a convenient approach for the fabrication of
composites with various spatial orders of the NPs.
A method for preparation of a composite based on the three-dimensional
nanosized copolymer template has been discussed [118]. The IPEC of the metallocontaining PEI-Ag
þ polycation with the ionic amphiphilic diblock copolymer
PS-b-PAA was obtained for further synthesis of encapsulated metal NPs. The silver
NPs with diameter 20–40 nm were successfully synthesized in coronas of micelles
(Fig. 24). In this case, PEI was used as both reducing and stabilizing agent. The
cryo-TEM images suggest that the Ag
þ content determines the size and spatial
distribution of silver NPs.
Polymer-assisted synthesis and environment-sensitive stabilization of metal
NPs can be achieved through the formation of IPECs based on diblock copolymers
in the presence of Ag
þ [97]. Silver NPs were obtained in micellar IPECs consisting of P2VPQ-b-PEO and PAA-block-poly(N-isopropyl acrylamide) (PAA-bPNIPAAm). Temperature was used to trigger the structural transition of a
core–shell structure. The P2VPQ and PAA segments acted as containers for Ag
þ
ions within micellar cores (25
C) or shells (60
C). PEO is supposed to ensure a
spontaneous reduction of Ag
þ to Ag through oxidation of the oxyethylene groups
[119] in the micellar IPECs. Control was demonstrated over the size of the formed
silver NPs, over the size and shape of the micelles containing the metal NPs,
and over the location of the silver NPs within the micellar IPECs. Spherical and
elongated micelles with the metal NPs were observed. The authors suggested a
potential application of such nanocomposites as environment-sensitive silver quantum dots and as antimicrobial agents in antifouling surface coatings that can be
216
D.V. Pergushov et al.
involves two simultaneous synergistic processes [80]: the formation of micelles
and polymerization of coordination supramolecules due to a sharp local increase
in the concentration of metallo-containing units. The cryo-TEM images prove
the formation of micelles with cores, which are highly contrasted by metal ions
(Fig. 22b).
The morphology of micellar IPECs is under the control of mixture stoichiometry. By direct mixing of the components at a 1:1 charge-to-charge ratio, spherical
micelles (Fig. 22) with a radius of ca. 25 nm are formed [80, 92]. Worm-like
micelles (Fig. 23) with a hydrodynamic radius of over 150 nm were found in a
mixture with excess positive charge [80, 92].
Design of advanced medicines and delivery drug systems has stimulated interest
in microcapsulation of magnetic or antibacterial NPs incorporated into polymers
[141, 142]. Fabrication of superfine catalytic or electronic devices is another
reason for development of hierarchically organized metallo-containing polymer
systems [95, 96, 143–145]. The nanostructured polymer systems give a fine tool
for control of NP growth through variation of the interface interactions [143].
Immobilization of metal NPs into polymeric matrices such as micelles [146],
microemulsions and microgels [147, 148], dendrimers [149, 150], block
co-/terpolymer self-/co-assemblies [95, 96, 143, 145, 151], and spherical polyelectrolyte brushes [152, 153] provides a convenient approach for the fabrication of
composites with various spatial orders of the NPs.
A method for preparation of a composite based on the three-dimensional
nanosized copolymer template has been discussed [118]. The IPEC of the metallocontaining PEI-Ag
þ polycation with the ionic amphiphilic diblock copolymer
PS-b-PAA was obtained for further synthesis of encapsulated metal NPs. The silver
NPs with diameter 20–40 nm were successfully synthesized in coronas of micelles
(Fig. 24). In this case, PEI was used as both reducing and stabilizing agent. The
cryo-TEM images suggest that the Ag
þ content determines the size and spatial
distribution of silver NPs.
Polymer-assisted synthesis and environment-sensitive stabilization of metal
NPs can be achieved through the formation of IPECs based on diblock copolymers
in the presence of Ag
þ [97]. Silver NPs were obtained in micellar IPECs consisting of P2VPQ-b-PEO and PAA-block-poly(N-isopropyl acrylamide) (PAA-bPNIPAAm). Temperature was used to trigger the structural transition of a
core–shell structure. The P2VPQ and PAA segments acted as containers for Ag
þ
ions within micellar cores (25
C) or shells (60
C). PEO is supposed to ensure a
spontaneous reduction of Ag
þ to Ag through oxidation of the oxyethylene groups
[119] in the micellar IPECs. Control was demonstrated over the size of the formed
silver NPs, over the size and shape of the micelles containing the metal NPs,
and over the location of the silver NPs within the micellar IPECs. Spherical and
elongated micelles with the metal NPs were observed. The authors suggested a
potential application of such nanocomposites as environment-sensitive silver quantum dots and as antimicrobial agents in antifouling surface coatings that can be
216
D.V. Pergushov et al.