Polybutene-1 (PB-1) grade Toppyl PB 8220M is a random copolymer of butene-1 with medium ethylene content.
This grade is highly compatible with polypropylene due to its similar molecular structure, and it is used to modify the sealing behavior of PP based films: a typical example is its use to reduce the seal initiation temperature of BOPP sealing layers.
The relatively slow kinetics of crystallization allow an excellent wetting behavior.
Toppyl PB 8220M highly shear-sensitive flow behavior means that it remains easily dispersible also in even more incompatible polymers like thermoplastic elastomers.
Toppyl PB 8220M can also be used in seal-peel application. Compared with Toppyl PB 8640M or Toppyl PB 8340M, in blown film seal-peel Toppyl PB 8220M provides better optical properties (haze and clarity) but with narrow sealing window.