by Abete T, Del Gado E, DE ARCANGELIS Lucilla, Serughetti DH, Djabourov M.
Abstract:
Experimental results have shown that the kinetics of bond formation in chemical cross-linking of gelatin solutions are strongly affected not only by gelatin and reactant concentrations but also by the solution pH. We present an extended numerical investigation of the phase diagram and of the kinetics of bond formation as a function of the pH, via Monte Carlo simulations of a lattice model for gelatin chains and reactant agent in solution. We find a re-entrant phase diagram, namely, gelation can be hindered either by loop formation at low reactant concentrations, or by saturation of chain active sites via formation of single bonds with a cross-linker at high reactant concentrations. The ratio of the characteristic times for the formation of the first and the second bond between the cross-linker and an active site of a chain is found to depend on the reactant reactivity, in good agreement with experimental data. (C) 2008 American Institute of Physics.
Reference:
Re-entrant phase diagram and pH effects in cross-linked gelatin gels (Abete T, Del Gado E, DE ARCANGELIS Lucilla, Serughetti DH, Djabourov M.), In THE JOURNAL OF CHEMICAL PHYSICS, volume 129, 2008. (Articolo in rivista)
Bibtex Entry:
@article{abe08,
author = {Abete T, and Del Gado E, and DE ARCANGELIS Lucilla, and Serughetti DH, and Djabourov M.,},
title = {Re-entrant phase diagram and pH effects in cross-linked gelatin gels},
volume = {129},
note = {Articolo in rivista},
issn = {0021-9606},
journal = {THE JOURNAL OF CHEMICAL PHYSICS},
doi = {10.1063/1.2985655},
year = {2008},
wosId = {000259876700052},
abstract = {Experimental results have shown that the kinetics of bond formation in chemical cross-linking of gelatin solutions are strongly affected not only by gelatin and reactant concentrations but also by the solution pH. We present an extended numerical investigation of the phase diagram and of the kinetics of bond formation as a function of the pH, via Monte Carlo simulations of a lattice model for gelatin chains and reactant agent in solution. We find a re-entrant phase diagram, namely, gelation can be hindered either by loop formation at low reactant concentrations, or by saturation of chain active sites via formation of single bonds with a cross-linker at high reactant concentrations. The ratio of the characteristic times for the formation of the first and the second bond between the cross-linker and an active site of a chain is found to depend on the reactant reactivity, in good agreement with experimental data. (C) 2008 American Institute of Physics.}
}