The delamination of metalized multilayer flexible packaging using a microperforation technique

Multilayer flexible packaging waste is a critical issue in the field of waste management as it is considered a non-recyclable material. One of the solutions to increase its recyclability is the delamination, which allows the recycling of the different polymer layers separately. This study investigated the optimization of the delamination by microperforating this plastic. The diffusion model was described by Fick's first law. The delamination process was tested at three different temperatures (50, 65 and 80 °C) with caustic soda. In addition, the influence of other parameters such as the thickness of aluminium layer, the presence of inks and the use of surfactants was tested. As a result, the microperforation technique improved the delamination rate by decreasing the residence time by 83% at the optimum conditions studied, being the thickness of the metal and the temperature essential factors affecting the process. However, the presence of inks and surfactant had no effect.