Optimal Process Condition and Blowing of Thermoplastic Polyester Film using Thermally Expandable Microcapsule

Abstract

Blowing film was prepared using polyester elastomer with thermally expandable microcapsule to investigate the optimum blowing properties and the film making process. Physical properties including specific gravity, blowing efficiency, foaming shape, tensile strength and elongation of polyester film were tested by varying the process condition of temperature and revolution per minutes of the extruder. The lowest specific gravity of 0.709 can be achieved with excellent foaming cells at 210℃ and 50 RPM conditions. The highest tensile strength and elongation was shown at 210℃, 100 RPM and 230℃, 25 RPM conditions. However, most of the prepared polyester films showed over 1kgf/mm2 of tensile strength which is reasonable value to use in film applications.