Dielectric studies of electrolytic poly(α-amino acid)s in aqueous solutions

✍ Scribed by Toshihiro Aiuchi; Norio Murai; Shintaro Sugai

• Publisher: Wiley (John Wiley & Sons)
• Year: 1974
• Tongue: English
• Weight: 488 KB
• Volume: 13
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.1974.360130718

✦ Synopsis

Abstract

The dependence of the dielectric constant and dielectric loss of aqueous solutions of poly‐ε, N‐succinyl‐L‐lysine on its degree of polymerization, degree of neutralization, concentration of the polymer, and counterion type was studied in a frequency range from 300 Hz to 5 MHz. Regardless of the conformation, a low‐frequency dispersion in a frequency range lower than 10 kHz and a high‐frequency dispersion in a range higher than 100 kHz were found. The large value of the dielectric increment, its nonlinear dependence on concentration, its remarkable dependence on counterion type, and its dependence on the degree of polymerization suggest that the low‐frequency dispersion is mainly due to the polarization of loosely bound counterions. These data were found for both the helical and coiled forms. The rotational motion of the electric dipole on the molecule could not have been primarily responsible for these results. On the other hand, the high‐frequency dispersions may be attributable to the Maxwell–Wagner‐type effect.

The results were compared with the dispersions of poly(L‐glutamic acid), poly(L‐lysine), and their salts reported previously.