ASTM International

Standard Test Method for Plastics: Dynamic Mechanical Properties Melt Rheology
 N D4440

Annotation

This test method outlines the use of dynamic mechanical instrumentation in determining and reporting the rheological properties of thermoplastic resins and other types of molten polymers. It may be used as a method for determining the complex viscosity and other significant viscoelastic characteristics of such materials as a function of frequency, strain amplitude, temperature, and time. Such properties may be influenced by fillers and other additives.

It incorporates a laboratory test method for determining the relevant rheological properties of a polymer melt subjected to various oscillatory deformations on an instrument of the type commonly referred to as a mechanical or dynamic spectrometer.

This test method is intended to provide a means of determining the rheological properties of molten polymers, such as thermoplastics and thermoplastic elastomers over a range of temperatures by nonresonant, forced-vibration techniques. Plots of modulus, viscosity, and tan delta as a function of dynamic oscillation (frequency), strain amplitude, temperature, and time are indicative of the viscoelastic properties of a molten polymer.

This test method is valid for a wide range of frequencies, typically from 0.01 to 100 Hz.

This test method is intended for homogenous and heterogeneous molten polymeric systems and composite formulations containing chemical additives, including fillers, reinforcements, stabilizers, plasticizers, flame retardants, impact modifiers, processing aids, and other important chemical additives often incorporated into a polymeric system for specific functional properties, and which could affect the processability and functional performance. These polymeric material systems have molten viscosities typically less than 106 Pa·s (107 poise).