Polybutene-1 (PB-1) grade Toppyl PB 8640M is a random copolymer of butene-1 with low ethylene content.

In blends with PE polymers it forms a separate but well-dispersed phase. Its primary use is as a minority blend component in the seal layer of easy-opening packaging films, produced by blown film extrusion. A typical PE blend partner forToppyl PB 8640M could be any ethylene homo-or copolymer in the melt index range of 0.7 to 2.0 g/10min.

Toppyl PB 8640M is also highly compatible with polypropylene due to its similar molecular structure, and it can be used to modify PP sealing behavior or mechanical properties such as impact strength. PB-1 crystallizes slowly and is very shear sensitive in its flow behavior.