Rheological Properties

Characterisation by rheology of polymer, liquid and adhesive samples over a wide variety of shear and extensional conditions.

Rheology Test Methods:

• Polymer processing, shear and extensional hot melt rheology.
• Capillary Rheometer
• Rotational Rheometer
• Coming soon! Instrumented injection moulding

Rotational Rheometer: Polymer melts, viscous fluids, dispersions, emulsions etc from ambient to 400°C.

• Very low shear rate analyses provide information on molecular weight.
• Gelation times can be determined for a wide range of materials, including epoxy resins and adhesives.
• Melt Stability in air or nitrogen atmosphere and/or against a range of metal surfaces.
• Effect of temperature on flow properties at fixed deformation rates.
• Thixotropy through controlled stress measurements of structured fluids.
• Yield stress, recovery, thixotropy, flocculation of multi-phase systems.

• Prediction of polymer melt processing behaviours e.g.
• Surface finish, weld lines, sink marks, warpage. fibre breakage, excessive draw, melt strength, edge curl, shrinkage, fibre coalescence, splitting, uneven width / thickness, bubble breaks, die drool.
• Gel Point Determination, Relaxation behaviours, Time/temperature dependency of Thermosetting,Thermoplastic and adhesive materials

The MSG advantage:

• Small scale polymer processing kit that can handle as little as 50g of sample.
• Bench top twin screw extruder (hopper volume 15cm 3) is able to compound/blend samples at temperatures up to 350°C.
• A haul off facility enables lace samples to be collected prior to cutting/pelletisation etc.
• The bench top injection moulding machine (also capable of operating up to 350°C) can then be used to mould samples of varying geometries including ASTM/DIN test pieces.
• Projects combined with other teams in MSG