Pay attention to when producing recycled PET material

In the production of recycled PET material packaging tape, if the use of recycled materials, the equipment status is as follows: single-screw 3 sections - 5 sections, drying temperature of 180 °C, baking 6-8 hours, processing temperature 250 °C - 260 °C. This time is very brittle and the scrap rate is high. How can we solve this problem?

PET is a water-sensitive plastic, long-term heating and drying of the material itself is easy to degrade, the friction heat of the single-screw extruder is also prone to degradation, so in the processing process, according to the actual situation to adjust the temperature, the material is very brittle Because of the severe chain breaking (degradation) during the production process, the molecular weight is too low and the viscosity is not sufficient. The resulting product is relatively brittle and the reject rate is too high.

Solution: Shorten the drying time to about 4-6 hours, add the chain extender (BASF JONCRYL can be selected), prevent degradation, extend the chain to increase the molecular weight, and increase the intrinsic viscosity. Products made in this way will not show brittleness and high reject rate due to insufficient viscosity.