The mixed impact of nanoclays on the apparent diffusion coefficient of additives in biodegradable polymers in contact with food

In face of growing environmental concerns, biodegradable and bio-sourced plastic nanocomposites are emerging as a new class of materials, especially for the food packaging sector. However, their use in food contact raises new issues in term of consumer safety.The aim of this study was to determine the impact of nanoclays on the apparent diffusion coefficient (Dapp) of selected additives from biopolymers into fatty food simulants. For the most part, nanoclay addition has a non-conventional impact. To understand this, the following parameters were studied: (i) the exfoliation state of nanoclay platelets in the polymer matrix, (ii) the sorption of food simulant by the polymer matrix, and (iii) the crystallinity of the materials. At first glance, solvent uptake and crystallinity agree with the results of diffusivity, however these parameters cannot explain the extreme differences between Dapp values