Radiowave dielectric properties of sodium maleate copolymers in aqueous solutions in light of a scaling approach.
The concentration dependence of the dielectric properties of aqueous solutions of sodium maleate copolymers with comonomers of different hydrophobicities have been investigated by means of frequency domain dielectric spectroscopy in the frequency range from 1 kHz to 2 GHz. The dielectric relaxation falling between the process at low frequencies (polarization involving the whole polymer chain) and the one at high frequencies (polarization of the bulk aqueous phase) has been analyzed in light of the scaling properties of polyelectrolyte solutions. Within this framework, the dielectric properties are governed by two characteristic lengths, the distance R(cm) between chains in the dilute regime and the correlation length xi in the semidilute regime. We find that, for both these regimes, the exponents of the scaling laws, which describe the dielectric increment Deltaepsilon and the relaxation time tau(ion) are in a reasonably good agreement with the ones experimentally observed. This analysis gives further support to the scaling approach of the dynamic behavior of polyelectrolytes, appearing very suitable to modeling our dielectric results.
Cametti
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Dipartimento di Fisica, Universita' di Roma La Sapienza, Piazzale A. Moro 2, I-00185 Rome, Italy. cesare.cametti@roma1.infn.it
Zuzzi
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D004573:Electrolytes / Q000737:chemistry; D008298:Maleates / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D014867:Water / Q000737:chemistry
D004573:Electrolytes; D008298:Maleates; D011108:Polymers; D014867:Water; C030272:maleic acid