Influence of the modification with polymer microspheres on the structural, mechanical and post-processing properties of extruded thin-walled LDPE films

This work describes the production in blown film extrusion process and characterization of the thin-walled LDPE films modified with polymer microspheres as the blowing agent. Mechanical properties of the films are investigated with the emphasis on the post-processing (welding process) as the most common for films and crucial for the applications in packaging industry. Moreover, barrier properties and wettability of the obtained films are considered and all of the properties are explained based on the microstructure of the materials. Research shown the influence of changed blowing agent content on selected physical and structural properties of thin-walled LDPE films, specially deterioration of static and dynamic mechanical properties, reduction of air and oxygen permeability and weal adhesion of microspheres to the LDPE matrix. Studies of welding shown the need to increase the welding temperature of porous films.