Title of article :
Thermal stability of gelatin gels: Effect of preparation conditions on the activation energy barrier to melting
Author/Authors :
Dranca، نويسنده , , Ion and Vyazovkin، نويسنده , , Sergey، نويسنده ,
Issue Information :
دوهفته نامه با شماره پیاپی سال 2009
Pages :
9
From page :
4859
To page :
4867
Abstract :
10, 20, and 40 wt.% aqueous gelatin gels were prepared under isothermal (annealing at 15, 20, and 25 °C for 15 to 120 min) and nonisothermal (cooling at 1 °C min−1) conditions. Isoconversional kinetic analysis of DSC data on gel melting (gel–sol transition) of all types of gels revealed significant variations in the activation energy throughout the process. Activation energy barrier to melting of isothermally prepared gels was in the range 160–190 kJ mol−1 and found to increase with increasing the annealing temperature that was the major effect discovered. Activation energy barrier to melting of nonisothermally prepared gels was determined to be around 120–140 kJ mol−1 and increase with increasing the concentration. Local reversibility of the gel melting was demonstrated by using temperature modulated DSC.
Keywords :
gelatin , Kinetics , Differential scanning calorimetry
Journal title :
Polymer
Serial Year :
2009
Journal title :
Polymer
Record number :
1733472
Link To Document :
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