Curling is a recurring problem in PA / PE asymmetric film extrusions for container lids and other packaging applications such as vacuum bags. The curved films have difficulty to be wound, printed or thermoformed correctly.

Curling problems are due to a different solidification temperature between polyamide and polyethylene. This problem can now be avoided thanks to our new a range of copolyamides.

Promyde BF940 is the benchmark for copolyamides in the market. It is an alternative to copolyamide 6/66 and stands out for eliminating curling and for its great transparency. In addition, NUREL offers a new range of copolyamides such as Promyde BF640, BF740 and BF745 that also obtain low curling results combined with high transparency.

This new development offers polymers whose intrinsic properties reduce curling in polyethylene-polyamide coextrusions, thus saving the hot water bath after treatment.