A model called the Menges/Klenk has been shown be appropriate for RPVC.
As a result, RPVC would not perform well on a barrier design using the principles of the Maddock/Tadmor model.
In fact, poor melt homogeneity has been my experience with Maddock/Tadmor type barrier screws processing RPVC.
They noted that the unique morphology of RPVC means it can often slide on metal surfaces rather than wetting them like most other polymers.
For RPVC extruders, the maximum screw speed is often set in the range of 25-35 ft/min peripheral speed, measured at the screw O.
The shallow feed depth or low compression ratio is also appropriate to the frictional coefficients of RPVC, which cause it to feed well.
Most RPVC is processed not on singles, but on counter-rotating twin screws.
The heads were not designed for rapid color changeover or for accumulator extrusion of thermally sensitive polymers such as FR-ABS, mPPO, and RPVC
In their Sheboygan, WI facility, Caeur OEM offers custom extrusion, including HDPE, LDPE, MDPE, PP, TPE, Urethane, FPVC, RPVC
, EVA and PVC/ABS alloy materials.
processing materials such as RPVC
, FPVC, PP, and TPE.
extruder running at 100 to 125 lb/hr) Polymer FPVC RPVC
ABS HIPS PC PET Drawdown, % 15-30 4-10 15-25 15-30 15-30 20-40 Polymer PETG CAP LDPE MDPE PP Drawdown, % 30-100 25-30 25-30 25-30 25-40
Also single-screw extruders designed to process a variety of materials including RPVC