Melt flow rate (MFR)

The flow properties of a polymer melt are critical to the performance of plastics in many packaging manufacturing processes such as injection moulding and blow moulding.

Melt flow rate testingThe melt flow rate (MFR) or melt flow index (MFI) of a plastic is the mass of molten polymer that flows through a standard die in 10 minutes. The polymer is forced through the die under pressure by applying a static loading to the piston in the heated barrel.

Pira uses a Hanatek melt flow indexer to determine the melt flow rate of a wide range of plastic polymers including polyethylene (PE), polypropylene (PP), polyamide (nylon) and polyethylene terephthalate (PET). A drier accessory is used to ensure that moisture sensitive polymers are thoroughly dried prior to testing.

Pira testing is made with reference to British standard BS 2782:720A, International standard ISO 1133 and ASTM D1238.

Expert Profile

  • Doug joined Pira in 1989 and has 20 years experience in the physical testing of packaging and packaging materials. He heads a team specialising in packaging and print related technical investigations. In 2004 Doug gained his postgraduate degree with distinction in Packaging Technology from Brunel University.

    Doug Leatherdale
    Doug Leatherdale

    Head of Physical Testing

    Pira International

    +44 1372 80 2108

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