Synthesis of Polyelectrolytes

Many ionogenic monomers containing a polymerizable carbon double bond have been reported in the literature, and therefore a wide variety of anionic, cationic, and amphophilic polyelectrolytes may be synthesized using free radical polymerizations. Examples of anionic ionogenic monomers which have been used to synthesize anionic polyelectrolytes include acrylic acid [4-10], methac-rylic acid [6-8,11,12], sodium styrenesulfonate [7,13,14], p-styrene carboxylic 

Free radical polymerizations may also be used to synthesize a host of cationic polyelectrolytes. Diallyl quaternary ammonium salts such as dimethyl-diallylammonium chloride, diallyldiethylammonium chloride, and diallylmethyl b-propionamido chloride are an interesting class of monomers which will 

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Sakharov IY, Vorobiev AC, Leon JJC (2003) Synthesis of polyelectrolyte complexes of polyaniline and sulfonated polystyrene by palm tree peroxidase. Enzyme Microb Technol 33 661-667... 

Starodubtsev SG, Khokhlov AR (2004) Synthesis of polyelectrolyte gels with embedded voids having charged walls. Macromolecules 37(6) 2004-2006... 

The synthesis of polyelectrolytes with well-defined architectures, however, has imposed many challenges to the polymer chemists. Many polymerization techniques are not tolerable to the ionic functional groups. In most cases, preparation of polyelectrolytes involves the protection and deprotection of the ionic groups in the monomer. For polyelectrolytes with different architectures, various synthetic strategies are required. Recently, we have synthesized various complex architectures containing polyelectrolytes with different nonlinear topologies, such as combshaped [22], hyperbranched [23-25], Janus-type [26], stars [27, 28] and brushes [29-31],... 

Controlled polymerization techniques have enabled the preparation of well-defined polyelectrolytes of different architectures. Polyelectrolyte stars and cylindrical brushes are two typical examples with isotropic and anisotropic nature, respectively. Different synthetic strategies have been developed for these polyelectrolytes. However, the core first and grafting from strategies have turned out to be the most suitable methods for the synthesis of polyelectrolyte stars and cylindrical brushes. 

Laschewsky A (2012) Recent trends in the synthesis of polyelectrolytes. Curr Opin Colloid... 

Rankin, D. and Lowe, A. (2006) Synthesis of polyelectrolytes via ring opening metathesis polymerization, Polyelectrolytes And Polyzwitterions Synthesis, Properties, And Applications, ACS Symposium Series, 937, 117-28. 

Figure 22.28 and Figure 22.29 show, respectively, the H and C-NMR spectra of the oligoesters prepared from epoxidized sunflower oil methyl esters (methyl biodiesel from sunflower oil) and di-l,2-cyclohexanedicarboxylic anhydride using triethylamine as initiator. These materials are soluble in common organic solvents such as acetone, ethanol, tetrahydrofurane, and chloroform, but insoluble in water. Oligoesters from epoxidized biodiesel can be used as intermediate materials for the synthesis of polyelectrolytes by saponification reactions with aqueous solution of sodium or potassium hydroxide at room temperature (Fig. 22.27). The products obtained after saponification present solubility in water. Amphiphilic materials, such as the polyelectrolytes prepared from epoxidized biodiesel, have hydrophobic and hydrophilic segments. They can spontaneously self-organize in a wide variety of structures in aqueous solution. Understanding the dynamics of the formation and transition between the various self-organized structures is important for technological applications.

Poly(arylene vinylenes). The use of the soluble precursor route has been successful in the case of poly(arylene vinylenes), both those containing ben2enoid and heteroaromatic species as the aryl groups. The simplest member of this family is poly(p-phenylene vinylene) [26009-24-5] (PPV). High molecular weight PPV is prepared via a soluble precursor route (99—105). The method involves the synthesis of the bis-sulfonium salt from /)-dichloromethylbenzene, followed by a sodium hydroxide elimination polymerization reaction at 0°C to produce an aqueous solution of a polyelectrolyte precursor polymer (11). This polyelectrolyte is then processed into films, foams, and fibers, and converted to PPV thermally (eq. 8). 

Interest in the chemistry of water-soluble polymers (polyelectrolytes) has been continually increasing during the past 45 years. The tremendous scope of utility for water-soluble polymers has led to a vigorous search for new materials and the rapid development of polyelectrolytes into a dynamic field of industrial research. Growth in this field has been especially rapid since 1960 and today, many companies are engaged in synthesis and applications research on polyelectrolytes that are primarily used in four main marketing areas water treatment, paper, textiles, and oil recovery [1]. Polyacrylamide gel was also used as soil conditioner [2-4]. 

Corner, T. Free Radical Polymerization — The Synthesis of Graft Copolymers. Vol. 62, pp. 95-142. Crescenzi, V. Some Recent Studies of Polyelectrolyte Solutions. Vol. 5, pp. 358-386. 

The general process involves polymerization of l,4-bis(dialkylsulfoniome-thyl)benzene dihalides (61) by addition of base. The immediately formed polyelectrolyte (62) is then converted thermally to the final PPV derivative (63). The process was first developed for the synthesis of unsubstituted PPV 60. The mechanism of the Wessling process is still not fully clear. First, Horhold et al. 

Several approaches have been tried in order to facilitate the conversion process and lower the conversion temperatures, e. g. by using appropriate sulfonium groups (tetrahydrothiophene derivatives) and/or different counter ions. With chloride as a counter ion [80], the synthesis of 2,5-dimethoxy-PPV can be performed at room temperature starting from the corresponding dimethylsulfon-ium polyelectrolyte precursor. 

Synthesis of poly(p-phenylene vinylene) films by thermal elimination on a soluble polyelectrolyte. 

Xu Q, An L, Wang S (2008) Design and synthesis of a new conjugated polyelectrolyte as a reversible pH sensor. Macromol Rapid Commun 29 390-395... 

Bmening, M.L. and Rnsling, J. (2006) in Modified Electrodes. Encyclopedia of Electrochemistry Vol. 10 Synthesis of Layered Polyelectrolyte Films (eds A.J. Bard, M. Stratmann, M. Fujihira, J.F. Rnsling and I. Rubinstein), Wdey-VCH, Weinheim. 

Scheme 4 Synthesis of surface-immobilized polyelectrolyte diblock copolymer (Si/Si02//PS-fc-PAA(Ag )) using ATRP...

Synthesis of monomers for the preparation of the methyl ester polyisocyanides begin with a-amino acid esters. These polyisocyanides were developed to yield optically active polymers which could be characterized first as non-electrolytes, and, after hydrolysis, as polyelectrolytes in aqueous media. As predicted, poly[a(carboxymethyl) alkyl isocyanides] are soluble in various solvents. Unfortunately, a low ceiling temperature, some instability to alkali and especially to... 

This article will summarize results and information derived from basic and applied research on DADMAC and its polymers. Contrarily to other specific publications, this review will include discussions of the synthesis, chemical structure, molecular characterization, polyelectrolyte behavior, complex formation, and applications. It will be shown that the real solution behavior of polyelectrolytes cannot be investigated separately from their chemical structure and that it is essential to study synthesis and characterization of polyelectrolytes along with their physico-chemical properties. 

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