INVESTIGADORES
CZERNER Marina
congresos y reuniones científicas
Título:
On the relationship between physical crosslinking density and fracture toughness in gelatin gels
Autor/es:
MARINA CZERNER; JOSEFA F. MARTUCCI; LAURA A. FASCE; ROXANA RUSECKAITE; PATRICIA M. FRONTINI
Reunión:
Conferencia; ICPB6 - 6th International Conference on Polymer Behavior; 2014
Resumen:
Gelatin forms physical gels in which the crosslinking points (junction
zones) are created by secondary ordered structures similar to the triple-helix arrangements
in native collagen. It is well documented that stiffness is dominated by
triple-helix concentration. This work explores whether fracture toughness is also
governed by triple-helix concentration. Several gel samples differing in
gelatin concentration, gelatin source (bovine or porcine) and solvent (water/water-glycerol/water-sorbitol)
are studied. Fracture toughness is determined by the Wire Cutting method at
100mm/min and the triple-helix concentration through the number-average
molecular weight between crosslinking points. Higher fracture toughness values
are obtained by increasing gelatin concentration, adding glycerol and sorbitol
as co-solvents and using porcine rather than bovine gelatin. All these observations
are consistent with the development of a more physically crosslinked structure
in the gels. Our results identify the relevance of triple helix-concentration
as key parameter controlling fracture toughness of gelatin gels.