Critical Exponents of Thermal Phase Transitions of kappa-Carrageenan in Various Salt Solutions

Tari O., Pekcan O.

48th Microsymposium on Polymer Colloids - From Design to Biomedical and Industrial Applications, Prague, Czech Republic, 20 - 24 July 2008, vol.281, pp.160-167 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 281
  • Doi Number: 10.1002/masy.200950721
  • City: Prague
  • Country: Czech Republic
  • Page Numbers: pp.160-167
  • Istanbul Technical University Affiliated: Yes

Abstract

The steady state fluorescence (SSF) technique was employed to study the phase transitions Of kappa-carrageenan in NaCl and KCl solutions. Pyranine was used as a fluorescence probe for monitoring these transitions. Scattered light, I(sc), and fluorescence intensity, 1, was monitored against temperature to determine transition temperatures and exponents. It was observed that transition temperatures are strongly correlated with the NaCl and KCl contents. The weight-average degree of polymerization, DP(w) and gel fraction G, exponents (gamma and beta) were measured and found to be in accord with the classical Flory-Stockmayer model.