Hydrodynamic, electrooptical, and conformational properties of stoichiometric polyelectrolyte complexes composed of poly(L-glutamic) acid and a cationic surfactant in chloroform and isopropyl and methyl alcohols were studied. In all these solvents, the molecules of the complex are individual compounds neither dissociating to separate components nor forming intermolecular associates. The optical rotation spectra of the solutions of the studied complex and its covalent analog, poly(γ-benzyl-α,L-glutamate), are characteristic of polypeptides occurring in the form of an α-helix. Comparison of the intrinsic viscosity η and the times of orientational relaxation τd of molecules shows that the hydrodynamic sizes of the complex molecules are markedly smaller than those of poly(γ-benzyl-α,L-glutamate) with the same degree of polymerization. A model is advanced according to which steric repulsion between bulky surfactant ions is responsible for the local disturbance of the secondary structure of the complex macromolecules; as a result, flexible fragments appear along with rigid helical regions. The presence of such fragments determines the compact convoluted conformation of the complex macromolecules in the examined solvents.

Original languageEnglish
Pages (from-to)1481-1487
Number of pages7
JournalVysokomolekularnye Soedineniya. Ser.A Ser.B Ser.C - Kratkie Soobshcheniya
Volume43
Issue number9
StatePublished - 2001

    Scopus subject areas

  • Polymers and Plastics
  • Materials Chemistry

ID: 94255029