BOPPHerstellung

BOPP Herstellung refers to the manufacturing process of biaxially oriented polypropylene film. This is a multi-stage process that begins with the extrusion of molten polypropylene resin through a die to form a thick, amorphous sheet. This sheet is then cooled rapidly on a chill roll. Following this initial extrusion, the film undergoes a stretching process in two perpendicular directions. First, the film is stretched in the machine direction (MD) at an elevated temperature, aligning the polymer chains along that axis. Subsequently, it is stretched in the transverse direction (TD) at a similar temperature, further orienting the polymer chains. This biaxial orientation is crucial as it imparts significant improvements in mechanical properties, such as tensile strength, stiffness, and puncture resistance, compared to unoriented films. After stretching, the film is annealed to set the orientation and then wound onto rolls. BOPP film is widely used in packaging, labels, and other industrial applications due to its clarity, barrier properties, and printability.