Rheological Analysis

Cambridge Polymer Group has world expert rheologists who can assist in developing the proper test methods for characterizing your material, interpreting your results, and making recommendations for formulation modifications. We have state of the art instrumentation, and develop custom fixtures for project-specific characterization. We have seen every kind of fluid, from low viscosity Newtonian materials through complex shear sensitive liquids and yielding and plastic fluids. Our detailed understanding of the phenomena and the instruments provides the highest chance of success and the most valuable understanding of the process at work.

We perform testing in compliance with the following standards (and others):

  • D4603 determining inherent viscosity of poly(ethylene terephthalate) (PET) by glass capillaryviscometer
  • D2857 dilute solution viscosity of polymers
  • D7271 viscoelastic properties of paste ink vehicle using an oscillatory rheometer
  • D445 Kinematic Viscosity of Transparent and Opaque Liquids
  • D3616 Rubber—Determination of Gel, Swelling Index, and Dilute Solution Viscosity
  • D5225 Measuring Solution Viscosity of Polymers with a Differential Viscometer
  • D789 Determination of Solution Viscosities of Polyamide
  • ISO 1628 Determination of the Viscosity of Polymers in Dilute Solution Using Capillary Viscometers
  • D1238 melt flow rates of thermoplastics
  • ISO 1133 Determination of the Melt mass-flow rate (MFR) and melt volume-flow rate (MVR) of thermoplastics
  • D2839 Use of a Melt Index Strand for Determining Density of Polyethylene


Shear Rheometry

Small amplitude oscillatory rheometry

  • Storage and Loss Modulus
  • Storage and Loss Viscosity
  • Strain-dependent properties
  • Gelation and melting kinetics

Steady Shear Rate

  • Shear viscosity as a function of shear rate
  • First normal stress coefficient
  • Yield stress determination


  • Material response to a fixed load

 Temperature Sweeps

  • Viscosity changes with temperature ramps

Extensional Rheometry

  • Extensional viscosity versus shear rate
  • Breakup time
  • Relaxation time determination