• adsorption;
  • diffusion;
  • stiffness;
  • modeling


An aqueous solution of glycerol was applied to a polymeric biomaterial, leather, to evaluate its effects on the physical properties of leather, particularly stiffness. The initial strain energy, Young's modulus, and acoustic-emission methods were used to characterize the stiffness of the resultant leather treated with these glycerol solutions. The measurements revealed that the glycerol treatment significantly reduced the stiffness of the dried leather, indicating the strong lubrication function of glycerol for leather. Experiments were also conducted to investigate the mechanism of glycerol adsorption into the leather matrix. Fick's second law of diffusion was employed to systematically derive a mathematical model for the absorption rate. The effect of temperature on the absorption rate was also included in the model by incorporation of the Arrhenius equation into Fick's second law of diffusion. The resultant model fits the experimental data very well. It not only depicts the mechanism of absorption but also predicts the absorption rate as a function of key variables. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1221–1231, 2003