Block copolymers, self-assembling functions

In dilute aqueous solutions, polyelectrolyte block copolymers self-assemble into micelles consisting of a hydrophobic core and a polyelectrolyte shell. The study of their structural properties is expected to provide a basic understanding of the properties of dense polyelectrolyte layers, electro-steric stabilization mechanisms, and actuator functions based on variations in the electrostatic interactions. 

The literature is abundant in describing the formation of spherical micelles from block copolymer self-assembly. From the classical diblock copolymer AB, two types of micelles could be prepared as a function of their structural parameters (Fig. 5). 

Figure 1 Synthetic strategies forthe preparation of molecular bmshes and their analogs (a) grafting through (b) grafting onto (X and Y are functional groups capable of coupling) (c) grafting from (I is an initiating group) and (d) block copolymer self-assembly approach.

Block copolymer self-assembly is a very promising alternative to make cylindrical polymer brushes. These brushes can replace the function and roles of molecular bmshes in many fields however, if the response of the main chain is necessary or in the case of multiblock copolymer side chains, they will fail to satisfy the application. 

J.K. Kim, S.Y. Yang, Y. Lee, Y. Kim, Functional nanomaterials based on block copolymer self-assembly. Progress in Polymer Science 35 (2010) 1325-1349. 

Amphiphilic block copolymers self-assemble in selective solvents such as water. Depending on parameters like overall average molecular weight, volume fraction of each block, or effective interaction energy between monomers in the blocks, vesicles with a bilayer shell and a solvent interior volume similar to liposomes are formed. They are often called polymersomes [241]. Such polymersomes in aqueous media have attracted increasing interest due to their enhanced stability compared to classical liposomes and due to the potential to control vesicle properties like bilayer thickness, permeability, or surface functionalities by appropriate chemical copolymer adjustment [242]. 

Synthesis of various functionalized 2008 [30] iV-isopropylacrylamide- and vinylether-based polymers grafting onto various substrates detailed review of thermoresponsive polymers, block and graft copolymers synthesis of PiPAAm of various shapes ionic and neutral block copolymers self-assembly stimuli-responsive polymers new initiating systems and synthetic methodologies... 

Sweat DP, Kim M, Yu X, Schmitt SK, Han E, Choi JW, Gopalan P (2013) A dual functional layer for block copolymer self-assembly and the growth of nanopattemed polymer brushes. Langmuir 29(41) 12858-12865... 

Fig. 1.3 Strategy for nanopatteming functional materials employing templates based on copolymer self-assembly with double-gyroid morphology. This approach is particularly versatile since it separates the template fabrication top row) from the templating of functional materials bottom row). 1 Copolymer synthesis. 2 Self-assembly into the double-gyroid morphology. 3 Selective degradation of one block yields a mesoporous template. 4 Templating of functional materials via various deposition techniques. 5 Removal of polymeric matrix. 6 Assembly of functional devices...

The distinctive properties of densely tethered chains were first noted by Alexander [7] in 1977. His theoretical analysis concerned the end-adsorption of terminally functionalized polymers on a flat surface. Further elaboration by de Gennes [8] and by Cantor [9] stressed the utility of tethered chains to the description of self-assembled block copolymers. The next important step was taken by Daoud and Cotton [10] in 1982 in a model for star polymers. This model generalizes the... 

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