Poly ionic interactions

It is well known that anionic samples tend to adsorb on poly(styrene-divinylbenzene) resins. However, cationic samples tend to be repelled from the resins. The mechanism seems to be an ionic interaction, although the poly(styrene-divinylbenzene) resin should be neutral. The reason is not well clarified. Therefore, it is recommended to add some salt in the elution solvent when adsorption or repulsion is observed in the analyses of polar samples. For example, polysulfone can be analyzed successfully using dimethylformamide containing 10 mM lithium bromide as an elution solvent, as shown in Fig. 4.42. 

Smith P. and Eisenberg A., lonomeric blends. I. Compatibilization of the polystyrene-poly(ethyl acrylate) system via ionic interactions, J. Polym. Sci., Polym Lett., 21, 223, 1983. 

Poly(L-lysine)-based hydrogel Ionic interaction pH [20]... 

Zhang and Bazuin reported the preparation of a series of ionically bonded side-chain polymer complexes, synthesized by 1 1 complexation of poly(styrenesulfonate) and quaternary ammonium-functionalized azo-containing surfactomesogens with hexyl and decyl spacers. Care was taken to work in extremely dry conditions to accomplish such syntheses. In most cases, the very strong ionic interactions lead to a crystalline structure, but in some instances, lamellar mesophases appeared. A very extensive annealing process was in many cases necessary to induce the formation of the mesophases because the chains were very less mobile, due to the relatively high... 

In the early 1950 s, B.F. Goodrich introduced the first commercial elastomer based on ionic interactions, a poly(butadiene-co-acry-lon1trile-co-acrylic acid). Typically less than 6% of carboxylic monomer 1s employed in order to preserve the elastomeric properties inherent in these systems. When neutralized to the zinc salt, these elastomers display enhanced tensile properties and improved adhesion compared to conventional copolymers. This enhancement of properties can be directly attributed to ionic associations between the metal carboxylate groups. 

In addition to the enhanced uptake of antigens by APCs, poly-L-arginine also exerts its adjuvant effects via the formation of a depot at the injection site (Fig. 3.3). This effect, which is based on ionic interaction of the vaccine components, prolongs the availability of antigen in the body. The consequences are most probably... 

Some recent examples demonstrating the molecular dispersion of rod polymer molecules in coil polymer matrices due to ionic interactions were given by Parker et al. (1996). These systems were based on three types of ionic PPTA s (Figure 5.4) and polar polymers, such as poly(4-vinylpyridine) (PVP), poly(vinyl chloride) (PVC), poly(ethylene oxide) (PEO), and poly(styrene-co-acrylonitrile) (S-AN). Due to the ionic-dipole interactions the rod-coil polymer pairs formed molecular composites as revealed by optical clarity, polarized microscopy, Tg measurements, as well as TEM observations. More significantly the molecular composites based on amorphous matrix polymers (e.g., PVP) were all transparent and showed no phase separation upon heating. Therefore they are melt-processible. As would expected, the mechanical properties of the molecular composites were... 

PANI has been doped with poly(amic acid) in order to obtain an all-polymer conducting material, by Angelo-poulos el a . [337]. Its structure has not been investigated, but the authors present x-ray diffraction results for cured specimens, in which polyimide formation has taken place at the expense of the carboxylic acid groups. The diffraction is structureless there is no indication that the elimination of the ionic interaction leads to phase separation of the polymers. 

A simple ion-exchange procedure allowed Fomal and Giannotti to immobilize Wio032" on poly(4-vinylpyridine), cross-linked methyl chloride quaternary salt [162]. The ionic interaction is strong enough to prevent the release of the polyoxoanion into the solution. This material has been investigated in the photooxidation of... 

The tetraanionic 47 (M = Cu, Zn, Ag, Cd R = -C6H4-SO3H) has been incorporated into different polymers including linear and cross-linked chloromethylated polystyrenes partially quartemized with pyridine (ionic interactions with the metal porphyrin), poly(4-vinylpyridine) (coordinative interactions with the metal porphyrin via the metal) and poly(ethylene glycol) (dipolar interactions with the metal porphyrin) [159,160]. Spectra of the samples were measured in solution or in the solid state. Red-shifts of both Q-and B-bands in the electronic spectra of the porphyrin occurred in the order poly(ethylene glycol) < poly(4-vinylpyridine) < quartemized poly(styrene). The greatest interaction occurred in ionic bonds between the carrier and the porphyrin [159]. 

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