Mold Flow and MFI Control

Improved mold flow can be achieved by several methods.

Melt Flow Reduction

One method of getting improved mold flow is to simply reduce the melt flow of the polymer.  This can be accomplished by better dispersing and coupling fillers and pigments into the resin matrix. This approach always produces a better quality product in the end. Use a quality dispersing additive to accomplish this. Melt flow can also be reduced by the use of an “internal lubricant”.  These are lower Mw polymers or additive molecules that act as a plasticizer in the melt phase.  Care must be taken is selecting these additives as they can harm the physical properties of the compound.  The last way is to simply use a lower MI resin. This is not the preferred approach because processing and physical properties will certainly be compromised.

Try: Trilsperse 800 for dispersion

Try: Trilwet 50 for wetting and internal MI reduction.

Mold Lubrication

Improved mold flow is commonly achieved by the use of a mold lubricant or good quality release aid.  These can affect how the compound flows into the mold and remove sticky spots in the mold. 

Try: Trilwax Si900

Surface Tension Control

The process of polymer flowing into a mold has a “wetting” component to it.  If the surface tension is controlled, better flow and wetting can be achieved. This is a similar phenomenon to spreading of coatings and paints.

Try: Trilwet PE101, Trilwet 50