PET is a packaging material for the future and new innovations keep coming to the market. Recently a new resin for EBM1 has been introduced. We have tested it and it works!

PET is an important and well known material in packaging applications and used in large quantities in flexible packaging, thermoforming and ISBM2 bottles.

Pet material development 

The ISBM process lack the ability to form handles on the product. This challenge is being addressed by the polymer producers and Invista has now introduced their new Polyclear® EBM PET 5505 which is designed with higher viscosity and melt strength for use in EBM operations and is suited for containers requiring a handle. The products can be recycled in the standard PET stream.

Extrusion blow moulding 

The EBM technology is commonly used for polyolefins. A key question for this processing industry is how PET will behave on a conventional machine. We wanted to find this out and have carried out extensive testing and modifications on our EBM line.

Our line is a Fischer W. Müller BFB 1-6 EBM machine with a 24D grooved feed screw designed for PE and PP extrusion.

Successful extrusion 

Our trials have been successful although we had several challenges. The photo below shows the bottles we have produced.

Main challenges vs. PE/PP:

• Drying of PET to achieve <50ppm H2O
• Extruder feed zone must be heated
• More sensitive adjustments of die gap and profile
• Higher extrusion temperature up to 285-295°C
• Parison cutting system must be modified
• High polished mould for transparency and gloss