A new lidding solution from DuPont Packaging & Industrial Polymers provides an easy and effective way to make peelable lids for retortable polypropylene (PP) packages. DuPont Appeel 22D843 lidding sealant resin is pellet-blended with a polypropylene sealant resin and then processed to make a lidding structure or sealant layer in conventional extrusion or coextrusion equipment designed for polyolefin resins.
“The new Appeel grade gives converters an easy way to tailor peel force and
achieve consistent sealing and peeling performance with a preformulated
masterbatch,” says Terry Kendig, senior technical development specialist of
DuPont Packaging & Industrial Polymers.
Appeel 22D843 is typically blended with PP at addition rates of 20 to 40
percent by weight. The proportion of Appeel in the blend determines peel
strength. Lower addition rates result in higher peel force and vice
Either homopolymer or copolymer PPs can be used. The choice of PP depends
on the melt index requirements of the extrusion process and performance
needs. Copolymer blends have a lower seal initiation temperature while
homopolymer blends may withstand higher retort temperatures. Appeel
22D843 is a PP-modified ethylene acrylate resin.
Blends of PP and the new Appeel grade can withstand sterilization conditions
from 121°C for 20 minutes up to 134°C for 6 minutes with adequate counter
pressure, depending on the type of PP employed.
DuPont Packaging & Industrial Polymers
New Resin Makes Peelable Seals for Retortable Polypropylene Packages
March 2, 2011