Kinetic and thermodynamic studies of silver migration from nanocomposites

To establish an applicable model and understand the release mechanisms from silver nanoparticle incorporated in polymeric film used in food applications, we investigated silver migration from low-density polyethylene film incorporated with silver nanoparticles in both distilled water and 4 w/v% acetic acid at various temperatures. The silver nanoparticle incorporated film was prepared from silver-containing master batch and was characterized to contain homogeneously distributed nanoparticles. The silver migration from the polymer matrix was well explained by the Korsmeyer-Peppas mathematical model. The resulting n value, ranging from 0.125 to 0.280, indicated that the silver migration followed Fickian diffusion. The kinetic rate constants (k) was higher in 4% acetic acid than in distilled water. According to the Arrhenius equation, the activation energy (E_a) was calculated to be 31.74 kJ mol⁻¹ for distilled water and 14.19 kJ mol⁻¹ for 4% acetic acid. Hence, the results of this investigation could be useful in predicting the silver release rate and understanding the mechanism of silver release from a LDPE matrix into food simulants.