Poly polyelectrolyte gels

Branched polyelectrolytes have become of special interest because of their industrial importance and scientifically interesting properties. Poly(ethyl-eneimine), which is important in various industrial applications, can provide an excellent example branched and linear polyelectrolytes have quite different properties due to both their different topographies and structures [89-91]. As another practical point, branched polyelectrolytes can act as precursor or fragments of polyelectrolyte gels. A variety of theoretical approaches have been reported on the investigations of branched polyelectrolytes [92-97]. However,... 

While the condition of stoichiometric neutrality invariably must hold for a macroscopic system such as a space-network polyelectrolyte gel, its application to the poly electrolyte molecule in an infinitely dilute solution may justifiably be questioned. In a polyelectrolyte gel of macroscopic size the minute excess charge is considered to occur in the surface layer (the gel being conductive), which is consistent with the assumption that the potential changes abruptly at the surface. This change is never truly abrupt, for it must take place throughout a layer extending to a depth which is of the order of magnitude of the... 

Changes in the dimensions of a polyelectrolyte gel may also result from a chemically induced ionization irrespective of isomerization. If this ionization is caused by irradiation with light and if the lifetime of the charged species is sufficiently long to permit the polymer to deform, a mechanophotochemical effect may result . This effect was described by Aviram in the case of poly[p-(N,N-dimethylamino)-N-y-D-glutamanilide] cross-linked with 1.5% 2,6-bis-(bromomethyI)naphthaIene on irradiation in the presence of carbon tetrabromide as an acceptor phoioionization occurs (Eq. (10)). 

This section is concerned with the poly(methacrylic acid) (PMAA) gel as the chemical gel where crosslinkages are composed of chemical bonds. The hydro-swollen polyelectrolyte gels, such as the PMAA, deform and change their volume in response to the change in environment as described in Section... 

Hirata M, Yamada Y, Kokufuta E. Effects of pH and alkyl sulfate surfactants on swelling equilibria for a cationic polyelectrolyte gel from poly-(ethyleneimine). In Schmitz K, ed. Macro-ion Characterization from Dilute Solutions to Complex Fluids. ACS Symp Ser, No 548. Washington DC Amer Chem Soc, 1994 493-498. 

It is well known that polyelectrolyte gels swell, shrink or bend when DC electric current is applied [169]. These properties of gels are applicable for the construction of chemomechanical devices, artificial muscles, energy conversion systems etc. [170]. Osada and co-workers [171] have constructed an eel-like gel actuator on the basis of poly(2-acrylamido-2-methylpropane sulfonic acid) and studied its chemomechanical properties. Polyampholyte gel is bent to the cathode or anode side if it has predominantly negative or positive charges along the macromolecules (Fig. 39) [172]. As seen from Fig. 39, the amplitude of deflection is gradually decreased with the approach to the lEP. This is probably due to... 

As to the weakly charged polyelectrolyte gels, they can be further subdivided into two classes. The first of these classes -gels with migrating (or annealed) charged units - is represented by partially neutralized poly(acrylic acid) (PAA) gel in water ... 

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