Melt Flow Rate ( Index)

Melt Flow Rate Testing Services

We test in accordance with ASTM D 1238,  ASTM D 3364, and ISO 1133

We have been testing melt flow of plastics since 1985 at University of Massachusetts, Lowell Campus. The Founders of Associated Polymer Labs lived between the north and south campus, and attended graduate school for 10 years. Associated Polymer Labs and Employees own 5 extrusion plastometers.  This is why we can offer the lowest price in North America for Polyolefins. 

Melt flow rate ( also known as MFR or MFI ) is the flow measurement of a thermoplastic melt.  It is defined as the mass of a plastic in grams, flowing in 10 minutes through a capillary of specific diameter and length via pressure applied by gravimetric weight. 

The melt flow rate is an indirect measure of molecular weight, with high melt flow rate corresponding to low molecular weight. Melt flow rate is an assessment of average molecular mass and is an inverse of the melt viscosity; in other words, the higher the MFR, the more plastic flows under test conditions. Knowing the MFR of a plastic is vital to anticipating and controlling its processing. Generally, higher MFR plastics are used in injection molding, and lower MFR plastics used in blow molding and extrusion. 

Many factors affect plastic MFR properties:  Molecular weight distribution, the presence of co-monomers, blends, the degree of chain branching, crystallinity, heat transfer, fillers, additives, and stabilizers.