Polymer groups ionized

In this section we briefly consider the osmotic pressure of polymers which carry an electric charge in solution. These include synthetic polymers with ionizable functional groups such as -NH2 and -COOH, as well as biopolymers such as proteins and nucleic acids. In this discussion we shall restrict our consideration... 

Terminology of polymers containing ionizable or ionic groups and of polymers containing ions (lUPAC Recommendations 2006), Pure Appl. Chem. 78, 2067-2074 (2006). Reprinted as Chapter 10, this edition. 

Terminology of polymers containing ionizable or ionic groups and of polymers containing... 

This document defines the most commonly used terms relating to polymers containing ionizable or ionic groups and to polymers containing ions. Inorganic materials, such as certain phosphates, silicates, etc., that also may be considered ionic polymers are excluded from the present document. Only those terms that could be defined without ambiguity are considered. Cross-references to terms defined elsewhere within the document are printed in italic type. 

An ionizable gel presents even more complications, since both solvent and ions must be transported into the gel in order to allow it to reach its equilibrium. In addition to solvent diffusion and polymer relaxation, ion diffusion and fixed charge group ionization rates must be considered. 

A conceptualization of the swelling processes at the front is shown in Fig. 15. Protons, attached either to water or to buffer, must climb a free energy hill in order to reach an amine at the front This hill is due either to the hydrophobicity of the groups surrounding the amine, or to the low dielectric constant of the dry polymer. After ionization is accomplished, the (protonated) amine will hydrate and move away from the dry polymer, into a more energetically favorable, wet environment. These two steps can be viewed as a kind of activated process, the transition state being the initially ionized, dry amine. 

Complexes between chiral polymers having ionizable groups, and achiral small molecules become, under certain conditions, optically active for the absorption regions of the achiral small molecules. Dyes such as acridine orange and methyl orange have been used as achiral species, since they are in rapport with biopolymers through ionic coupling. This phenomenon has been applied to the detection of the helix chirality in poly-a-amino acids, polynucleotides, or polysaccharides when instrumental limitations prevent direct detection of the helices. 

Additional water uptake. The amount of the absorbed water steadily increases due to the steadily increasing amount of ionized polymer groups induced by the additive (Gerlach et al. 2005 Guenther et al. 2007a). 

Polymers with ionizable phthalic acid groups dissolve faster at a lower pH than polymers with acrylic or methacrylic acid groups (Table 2). The simple coacervation of hydroxypro-pyl methylcellulose phthalate (HPMCP) with the addition of a 20% sodium sulfate solution was studied. Coacervation is the method of choice for the production of pharmaceutical preparations having a high active ingredient content and a smaller particle size of core materials used. With an increase in pH, the electrolyte (sodium sulfate) amount required to... 

Conjugated polymers are powerfiil fluorescent materials, which makes them suitable for applications as chemical sensors. Chart 13.1 presents the structures of some typical polymers that are applicable for the detection of analytes at low concentrations. These polymers include poly(p-phenylene ethynylene), PPE poly(p-phenylene vinylene), PPV polyacetylene and polyfluorene. Those polymers bearing ionizable pendant groups are water-soluble polyelectrolytes. 

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