The melt flow rate is a measure of the rate of extrusion of molten thermoplastic resins by means of an extrusion plastometer. Knowledge of the melt flow rate of a thermoplastic polymer gives the certainty that the material can be used safely and reliably in the field. As a specialist in materials testing, Element provides melt flow rate testing by ASTM D1238 to help you making predictions of how your polymers will behave at different temperatures and under a wide variety of mechanical stresses. 

Melt flow rate testing of thermoplastic polymers is particularly useful in quality control to verify in-house materials or to quality check entrance materials. Melt flow rate testing is also a valuable tool to compare new materials in a product development setting (thermal stability and molecular weight comparison), or as part of full failure investigations. 

Melt flow rate test procedure

The basic property measured during a melt flow testing is the melt viscosity, or the ability of a polymer’s melt to flow at a specified shear stress (related to the applied load) and temperature. During the test, a small amount of a thermoplastic sample is heated in a barrel at a definite temperature, melted to a viscous fluid, and forced out of a standardized die by a piston loaded with dead weight. Once enough sample has extruded, it is removed and weighed, or the volume of the sample is measured by the machine.

Materials we commonly test

We test a variety of amorphous and semi-crystalline polymers, such as nylon, polyester, and polycarbonate that require drying at a specified moisture level before testing, as well as polyolefin polymers that do not require prior treatment. 

ASTM D1238

Element’s highly qualified polymeric materials experts provide melt flow rate testing of thermoplastic materials in accordance with ASTM D1238, performing both procedure A and procedure B to determine the melt flow rate (MFR) and the melt volume rate (MVR) of your thermoplastic material. 

Experts in polymeric materials testing

Our extensive knowledge in polymeric materials allows us to provide highly specialized and value-added material testing services. Partnering with Element will help you make sure that your materials are safe and suitable for their intended applications. 


For more information about our melt flow rate testing services, or to speak to an expert, contact us today.

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