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Coating PP on Al in seal-peel application

We are currently working on a project to coat PP melt on Aluminium substrate, the material which would be acceptable for seal-peel packaging applications. The question is: Have we chosen correctly Moplen HP 522J for this in blend with PB-1? What is your suggestion?

Best regards,

NEVENKA MARIC
DIOKI d.d. Lokacija Omisalj - NJivice, CROATIA

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Dear Nevenka Maric,

I work for a company that develops and commercializes Polybutene-1 (PB-1). One of the major applications for PB-1 is the seal-peel structures for packaging. PB-1 main benefit is the possibility to taylor and control the peeling force, that is homogeneous and consistent. Also, it provides a broad sealing temperature window and tamper evidence.

To be able to help you designing a suitable seal-peel structure involving PB-1, I would need more details like: type of packaging and structure, substrate materials involved (aluminium, PP, PE ?), level of peeling force required, method of film production (blown film, cast film).

Thanks,

Regards,

Wladimir Moraes
- Paris, France

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Having some experience with production of cast PP films I found PB1 did not produce good peel seals. PB is compatible with PP so you do not get the smooth cohesive failure required for a good peel seal. In fact blending PB to PP can produce an effective sealing layer with relatively low temperature seal. Had some success with blending mLLDPE with PP to achieve a peel seal. mLLDPE needed to have density <0.905 to get good dispersion in PP. In the end it will depend on your application.

Steve Geard
- Auckland, New Zealand