A series of tests conducted by Coperion, a maker of compounding and extrusion systems and other plastics processing equipment, and Lummus Novolen Technology successfully demonstrated the production of polypropylene (PP) pellets with very low melt viscosities using Coperion’s ZSK extruders. Melt-blown PP forms the raw material for nonwovens used as filter media in medical-grade face masks. The tests carried out at Coperion’s lab in Stuttgart, Germany, showed that the concept can be easily scaled to production quantities, said Coperion. Lummus Novolen Technology, which licenses polypropylene technology and provides related engineering and technical support, holds the license for the production process.
The tests are based on Coperion’s ZSK extruder technology with ZS-EG side devolatilization and a screw design tailored exclusively for Novolen. According to Heiko Hornberger, Head of Team Polyolefins, Process Technology, at Coperion: “The innovative system concept proves the successful interaction of different technologies — the combination of a new screw concept for optimum dispersion and very good degassing thanks to ZS-EG technology secures first-class product qualities. This is achieved with outstanding process reliability, regardless of throughput rates and melt viscosity. The overall concept of the Coperion system not only ensures the operational flexibility required by the licensor for the processability of a broad range of PP types, but also significantly extends the possible application window,” said Hornberger.
|A new screw concept and good degassing thanks to ZS-EG extruder technology results in process reliability, regardless of throughput rates and melt viscosity, according to Coperion. Image courtesy Coperion.|
"With this process, the licensees of Lummus Novolen Technology are now able to produce these coveted products safely and reliably, without restrictions on the existing product portfolio,” said Sebastian Schwarzer, Technology Manager Extrusion at Lummus Novolen Technology. “Furthermore, the project impressively shows that the interaction between the technological expertise of Lummus Novolen Technology and the innovative system design and competence of Coperion leads to the desired success within the shortest development time,” added Schwarzer.
The process design package, which contains all necessary process parameters and additive recipes, can be licensed through Lummus Novolen Technology. Coperion supplies the machine components.