In 2021, the International Committee of the Red Cross (ICRC), the United Nations World Food Program (WFP) and the United Nations High Commissioner for Refugees (UNHCR) launched a joint project to investigate alternatives and innovative solutions to polypropylene bags used for food and relief packaging.

The three humanitarian organizations, rooted in the procurement and provision of essential goods to some of the world's most vulnerable and marginalized communities, supply millions of tons of food and non-food items globally.

The Polymer Materials Engineering (IMP) Laboratory at the Institute of Mechanical Engineering and Materials Technology (MEMTi) is participating in the "Alternatives to PP bags" project, funded by Innovation Norway and led by ICRC, to address this issue through the application of eco-design principles to identify and develop potential alternatives. The material produced must also meet criteria inherent to carrying capacity (5 to 90 kg) as well as specific quality criteria, such as resistance to UV light, pests, etc.

The IMP research group, led by Prof. Andrea Castrovinci, worked in this project together with GiottoIndustrial Networking SA, a Swiss technical textile competence center based in Ticino. The combination of IMP and GiottoIndustiral expertise made it possible to develop a solution that met all the criteria defined in the project. The research work focused on jute fabric, a fiber of plant origin with mechanical characteristics comparable to those of polypropylene, but less resistant to water and to possible attacks by microorganisms such as fungi and bacteria. To replace polypropylene with jute, a treatment was therefore developed to make the latter water-repellent and antibacterial, taking advantage of the Layer by Layer (LBL) approach.

This technique makes it possible to reinforce the plant fiber through a solution aimed at improving the fabric's performance; specifically, the LbL approach was exploited to combine an antibacterial agent, silver nitrate, and a hydrophobic polymer precursor in the coating to reduce the fiber's interaction with water.