Poly zwitterions

Previously, wel had shown that hydrophobically associating polymers can be isoviscous in salt solutions of increasing brine level. We [13,14] and others [15,16] has also shown that aqueous poly zwitterions are antipolyelectrolytes i.e. their solubility and viscosity increases with increasing salt content. 

Poly-zwitterions differ from polyampholytes in that both the cationic and anionic species are on the same monomer residue, consisting of a quaternary ammonium, which is a cationic moiety, and sulfonate (sulfobetaines), carboxylate (carbo- or... 

Fig. 3 a-c. Summary of data from different laboratories, obtained by surface force measurement, on the average layer thickness L as a function of tethered chain length for flat, tethered layers constructed by adsorption of amphiphilic polymers on mica. Adapted from Ref. 21. (a) Data of reference 20 on poly-tert-butylstyrene chains anchored by adsorbing blocks of poly-2-vinylpyridine. (b) Data of references 11 and 12 on polystyrene chains anchored by adsorbing blocks of poly-2-vinylpyridine. (c) Data of references 13 and 14 on polystyrene chains anchored by adsorbing zwitterionic groups [13] or by small adsorbing blocks of polyethyleneoxide [14]... 

This paper describes the synthesis and characterization of a new zwitterionic water-soluble thiosulfate polymer (Poly[7-(amino -thiosulfate) etheij-PATE) via chemical reaction of a diglicydyl ether of bisphenol A (DGEBA) with aminoethane thiosulfuric acid (AETSA) as a reactive... 

Note An ampholytic polymer in which ionic groups of opposite sign are incorporated into the same pendant groups is called, depending on the structure of the pendant groups, a zwitterionic polymer, polymeric inner salt, or poly betaine. 

Spontaneous polymerization of 4-vinyl pyridine in the presence of polyacids was one of the earliest cases of template polymerization studied. Vinyl pyridine polymerizes without an additional initiator in the presence of both low molecular weight acids and polyacids such as poly(acrylic acid), poly(methacrylic acid), polyCvinyl phosphonic acid), or poly(styrene sulfonic acid). The polyacids, in comparison with low molecular weight acids, support much higher initial rates of polymerization and lead to different kinetic equations. The authors suggested that the reaction was initiated by zwitterions. The chain reaction mechanism includes anion addition to activated double bonds of quaternary salt molecules of 4-vinylpyridine, then propagation in the activated center, and termination of the growing center by protonization. The proposed structure of the product, obtained in the case of poly(acrylic acid), used as a template is ... 

The ionic domain of polyelectrolytes also affects the photoinduced charge separation between the coexisting low molecular charged compounds38). The quenching of Ru(bpy)2 + by a zwitterion compound, dibenzylsulphonates viologen (18, BSV), was enhanced about 4 times by poly(vinylsulphate) (PVS)39), and the back reaction... 

In a slightly different system, Matsuo14 149 also examined electron transfer to a polymer supported viologen [ poly(JV-vinylbenzyl-7V -n-butyl-4,4 -bipyridinium PV2+] via a zwitterionic viologen (N,N -bis(3-sulfonatopropyl)-4,4 -bipyridinium PSV). 

Exclusive polymerization of phenylacetylene takes place, unexpectedly, under hydrosilylation conditions in the presence of a zwitterionic Rh(I) complex, [Rh(COD)]+BPh4, and HSiEt3 to give all-ds-poly(phenylacetylene)285. 

More recently, Chen et al. described a surface modification whereby the polymer poly(Ar,Ar-dimethyl-Af-(ethoxycarbonylmethyl)-Ar-[2/-(methacryloyloxy)ethyl]-ammonium bromide) was grafted from a surface via ATRP [136], The cationic polymer effectively kills E. coli and is subsequently converted into a zwitterionic polymer by hydrolysis of the head group (Fig. 9). It then repels all attached cells dead or alive. This is the first example of a surface that can kill microbes on contact and repels them after that. The only downside of this elegant system is that it will eventually exhaust and turn into a more or less effective repelling surface. 

Ethyleneimine has been also copolymerized in the absence of an initiator by zwitterion copolymerization with maleic anhydride [79] and methacrylic acid [80]. Both copolymers were checked following the batch method for copper(II), uranium(VI) and iron(III) and did not adsorb iron(HI), but copper(II) and uranium(VI) at pH 2. Poly (ethyleneimine-co-methacrylic acid) adsorbed more than 95% UO +. The ions were almost quantitatively eluted by contact of the loaded resin with 1 M aq. H2S04 [79, 80]. 

Poly(alkyl-cyanoacrylates) As poly(alkyl-cyanoacrylates) form strong bonds with polar substrates including the skin and living tissues, they exhibit bioadhesive properties. These polymers are synthesized by free-radical, anionic, or zwitterionic polymerization. As detailed in a recent review, poly(alkyl-cyanoacrylate) nanoparticles are prepared by emulsion polymerization, interfacial polymerization, nanoprecipitation, and emulsion-solvent evaporation methods [102],... 

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