Technological watch

The growing interest in sustainable, lightweight, bendable roll?to?roll manufactured printed electronics applied to packaging, textiles or medical healthcare has led to the need for materials that can withstand various environmental conditions. In this work, the studied materials were polyethylene terephthalate (PET), typically used as a substrate for printed electronics, and it was compared to biobased polymeric substrates bio?PET, polylactic acid (PLA), cellulose acetate propionate (CAP) and regenerated cellulose film Natureflex™. Films were exposed for 500?h to heat (50.5°C); heat and humidity (50 RH%); heat, humidity, and light (UV?A 300–400?nm, 42?W/m2) and temperature cycles in the range of ?45°C to 65°C. Changes in film transparency and mechanical properties were analyzed. The main findings were that during the exposure to only elevated temperature and temperature with humidity, the analyzed properties were retained in all film materials. UV?A caused less or no changes in Natureflex™, bio?PET and PLA. The most stable in thermal cycling was Natureflex™, CAP, and PET. These results may open new possibilities for biopolymers in printed electronics applications.