Drawing and rolling of poly(ethylene terephthalate) sheets prepared from used PET bottles

Initially amorphous PET sheets were prepared from recycled flake made from postconsumer PET bottles. Drawing and/or rolling of the sheets were performed at 80 degrees C using a draw ratio up to 4.2. The influence of draw ratio on the structure, molecular orientation, and mechanical properties of drawn sheet was investigated. Not only was the tensile strength at yield stronger, but the modulus of the deformed sheets was much higher than that of as- extruded sheets. This was attributed to the enhanced chain orientation and crystallinity of PET with increasing draw ratio. In this work, no particular inferiority in the mechanical properties of PET sheets recycled from used PET bottles (compared with the fresh virgin bottle grade resin) could be seen.