Critical Exponents of Kappa Carrageenan in the Coil-Helix and Helix-Coil Hysteresis Loops


Tari O., KARA S., Pekcan O.

JOURNAL OF MACROMOLECULAR SCIENCE PART B-PHYSICS, vol.48, no.4, pp.812-822, 2009 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 48 Issue: 4
  • Publication Date: 2009
  • Doi Number: 10.1080/00222340902956129
  • Title of Journal : JOURNAL OF MACROMOLECULAR SCIENCE PART B-PHYSICS
  • Page Numbers: pp.812-822

Abstract

The steady-state fluorescence technique was used to study coil-helix (sol-gel) and helix-coil (gel-sol) transitions of the kappa carrageenan-water system with various carrageenan contents. Fluorescence (I) and scattered light (I-sc) intensities were measured against temperature to determine critical phase transition temperatures and exponents. It was observed that the coil-helix transition temperatures, T-ch were much lower than the helix-coil (T-hc) transition temperatures due to the hysteresis of the phase transition loops. The gel fraction exponent (beta) was measured and found to be in accord with the classical Flory-Stockmayer model.