Characterization and properties of gellan-kappa-carrageenan mixed gels

This paper concerns the properties of gellan and kappa-carrageenan mixtures in the dilute and semi-dilute regimes. For the purified K-forms of the two polymers at low polymer concentrations, a cooperative interaction between their ordered conformations is demonstrated from viscosity measurements. At higher polymer concentrations a two-phase system is formed as shown from differential scanning calorimetry and rheological measurements. From these data, it is concluded that the gellan and kappa-carrageenan mixed gel is a phase separated gel. The role of ionic impurities (such as Ca2+ ions) on the position of the melting temperatures of the two phases is also discussed.