The Recycling Technologies of Mono-material and Multilayer Plastic Film: A Descriptive Literature Review

Plastic-based flexible films are widely used in many areas of modern industry, including the food industry. Depending on the application field, mono-material or multi-material films can be used, usually based on polyolefins such as PE and/or PP. Compared to mono-material films, multilayer films offer greater performance and functionality in terms of mechanical and barrier properties, thanks to the different types of polymers used. Considering the end-of-life of the two types of materials, the recyclability of mono-material film turns out to be much greater than that of a multilayer, since only one type of polymer can be handled in specific and specialized streams. The biggest issue with multilayer films is precisely end-of-life management, which currently appears to be mainly landfilling or waste-to-energy. In recent years, the use of increasingly sustainable packaging has become a prerequisite. The issue of recycling is of fundamental importance because of the implementation of a circular economy. This review aims to investigate recycling methodologies for both mono-material and multi-material films, from traditional ones, such as mechanical recycling, to more modern technologies not widely used in industry, such as delamination and chemical recycling.