Monday 1 August 2011

plastic plate flakes



                                        Pet Preforms  
bottle flakes n order to save costs, an increasing number of polyester intermediate producers like spinning mills, strapping mills or cast film mills are working on the direct use of the PET-flakes, from the treatment of used Pet Preforms bottles, with a view to manufacturing an increasing number of polyester intermediates. For the adjustment of the necessary viscosity, besides an efficient drying of the flakes, it is possibly necessary to also reconstitute the viscosity through polycondensation in the melt phase or solid-state polycondensation of the flakes. The latest PET flake conversion processes are applying twin screw extruders, multi-screw extruders or multi-rotation systems and coincidental vacuum degassing to remove moisture and avoid flake pre-drying. These processes allow the conversion of undried PET flakes without substantial viscosity decrease caused by hydrolysis.Looking at the consumption of PET bottle flakes, the main portion of about 70% is converted to fibers and filaments. When using directly secondary materials such as bottle flakes in spinning processes, there are a few processing principles to obtain.

High speed spinning processes for the manufacture of POY normally need a viscosity of 0.62–0.64 dℓ/g. Starting from bottle flakes, the viscosity can be set via the degree of drying. The additional use of TiO2 is necessary for full dull or semi dull yarn. In order to protect the spinnerets, an efficient filtration of the melt is, in any case is necessary. For the time being the amount of POY made of 100% recycling polyester is rather low because this process requires high purity of spinning melt. Most of the time a blend of virgin and recycled pellets is used.

Share/Bookmark

1 comment:

  1. Preform mold suppliers can also be credited with coming up with a technology that is environmentally friendly.

    Preform Mold Supplier

    ReplyDelete