Hysteresis during sol-gel and gel-sol phase transitions of kappa-carrageenan: A photon transmission study


Kara S., Tamerler C., Bermek H. , Pekcan O.

JOURNAL OF BIOACTIVE AND COMPATIBLE POLYMERS, vol.18, no.1, pp.33-44, 2003 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 18 Issue: 1
  • Publication Date: 2003
  • Doi Number: 10.1177/088391103032793
  • Title of Journal : JOURNAL OF BIOACTIVE AND COMPATIBLE POLYMERS
  • Page Numbers: pp.33-44

Abstract

Photon transmission techniques were used to study sol-gel and gel-sol transitions in kappa-carrageenan-water systems with various carrageenan contents. The photon transmission intensity, I-tr was monitored against temperature to determine critical phase transition temperatures and transition rates. It was observed that the sol-gel transition temperatures, T-sg, were found much lower than the gel-sol, T-gs, transition temperatures based on the hysteresis of the phase transition loops. Sol-gel and gel-sol activation energies were determined and it was found that a carrageenan-water system required less energy for the gel-sol transition than for the sol-gel transition.