Amphiphilic poly electrolytes

Morishima, Y. Photoinduced Electron Transfer in Amphiphilic Poly electrolyte Systems. Vol. 104, pp. 51-96. 

This chapter deals with a recently developed unimer micelle, a novel intramolecular assembly with a higher-order structure, formed from tailored amphiphilic random copolymers bearing charge and bulky hydrophobes. The first half of this chapter will be devoted to the synthesis of such amphiphilic poly electrolytes and characterization of the unimer micelle. The functionalization of the unimer micelles with chromophoric molecules and some functional properties of these functionalized unimer micelles will be described in some detail in the second half of this chapter. 

FIG. 9 Schematic illustration of adsorption of poly(styrenesulfonate) on an oppositely charged surface. For an amphiphile surface in pure water or in simple electrolyte solutions, dissociation of charged groups leads to buildup of a classical double layer, (a) In the initial stage of adsorption, the polymer forms stoichiometric ion pairs and the layer becomes electroneutral, (b) At higher polyion concentrations, a process of restructuring of the adsorbed polymer builds a new double layer by additional binding of the polymer. 

Amphiphilic diblock copolymers undergo a self-assembly micellar process in solvents that are selective for one of the blocks [100]. By choosing selective conditions for each block, conventional micelles and so-called inverse micelles can be formed. Examples of the so-called schizophrenic micelles were reported [101]. In this case hydrophilic AB diblock copolymers can form micelles in an aqueous solution, in which the A block forms the inner core and inverted micelles (with the B block forming the iimer core) [102]. A diblock copolymer with two weak polybases, (poly-[2-(N-morphoUno)ethyl methacrylate-i)Iock-2- and (diethyl amino)ethyl methacrylate) (PMEMA-block-DEAEMA), forms stable micelles with DEAEMA cores by adjusting the pH value of the solution. The formation of inverted micelles (MEMA core) was achieved by a salting out effect by adding electrolytes to the aqueous solution. 

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