Thermal stability of gelatin gels: Effect of preparation conditions on the activation energy barrier to melting

✍ Scribed by Ion Dranca; Sergey Vyazovkin

• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 528 KB
• Volume: 50
• Category: Article
• ISSN: 0032-3861
• DOI: 10.1016/j.polymer.2009.06.070

✦ Synopsis

a b s t r a c t 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 À1 ) 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 À1 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 À1 and increase with increasing the concentration. Local reversibility of the gel melting was demonstrated by using temperature modulated DSC.