Custom Compounders Since 1973

TPGOA Technical Insights

Controlled Viscosity Additives

MFI (Melt Flow Index) is a standard measurement within the Polypropylene compound market space.

There are many shortcomings with this value. The shear rates generated during testing are extremely low, and all polymer viscosities are based on varying shear rates at a given temperature. Additionally, it is single point data, which does not characterize the polymer over a variety of shear rates.

However, everyone needs an MFI number regardless. Several suppliers have developed packages to adjust MFI and maintain or improve physical properties. These packages provide external lubrication as well. This will allow parts to release from the mold with less ejection force.

Previous attempts to alter MFI included the blending of different MFI base resins, or the addition of peroxide based additives.

These new additives make arriving at a target MFI easier than other methods.

TPG makes every effort to insure that the information contained herein is accurate - however, we accept no liability for the content of this piece, or for the consequences of any actions taken on the basis of the information provided.
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