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Persistence length of the chain

The situation is more favourable for the study of EB in solutions of flexible-chain polyelectrolytes for which the value of K may be higher by several orders of msg-nitude than for molecules bearing no charge This seems plausible since the uncoiling of a flexible-chain polyion by electrostatic repulsion of ionc enic groups increases the persistent length of the chain and the optical and hydrodynamic properties of the molecule approach those of a rigid-chain polymer ... [Pg.168]

Figure 13. Change of the persistence length of the chain upon going from the isotropic to the nematic state. Figure 13. Change of the persistence length of the chain upon going from the isotropic to the nematic state.
Consider a linear polyelectrolyte chain with m monomer units. Each monomer xmit contains a chemical moiety that is sensitive to the aqueous environment. Examples of such groups include carboxylic acids, amine bases, or generalized bases with the corresponding coxmterions such as sulfate and sodium ions. For convenience, we will restrict attention to monovalent systems, but more complicated polymers such as DNA can be treated in the same manner. If the chain in dilute aqueous solution is electrically neutral, the conformation will be determined by the persistence length of the chain, the overall chain length, and the solvent quality, just as for any linear polymer in dilute solution. However, dissociation of some of the species in... [Pg.119]

The cross-over value q is related to the persistence length of the chain by... [Pg.124]

Similar measurements on main chain liquid crystal polymers have been used to determine the persistence length of the chains in the nematic phase. Again, there are theoretical predictions for the temperature behavior. It has been suggested that as the temperature increases the number of hairpin bends of the chain will increase and the conformation of the chain will become more isotropic [26]. This has been confirmed qualitatively, but since most of the materials have been polyesters and have had nematic phases at quite high temperatures the effects of transesterification have interfered [27-30]. However, similar results have been found in a polyether [31] where the chains were found to contain one hairpin defect on average. [Pg.718]

See other pages where Persistence length of the chain is mentioned: [Pg.601]    [Pg.552]    [Pg.11]    [Pg.51]    [Pg.120]    [Pg.275]    [Pg.521]    [Pg.105]    [Pg.200]    [Pg.186]    [Pg.186]    [Pg.33]    [Pg.247]    [Pg.330]    [Pg.23]    [Pg.105]    [Pg.271]    [Pg.60]    [Pg.125]    [Pg.61]    [Pg.78]    [Pg.3]    [Pg.69]    [Pg.11]    [Pg.398]   
See also in sourсe #XX -- [ Pg.61 ]



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