Axiom Analytical has announced the availability of its FDR-755 extruder access optical diffuse reflectance probes, designed for analysing polymer melts during extrusion.
Near-infrared (NIR) spectroscopy provides a means for monitoring the chemical composition of numerous substances during manufacture.
It has found broad application in fields ranging from the analysis of agricultural products to in-line monitoring of both continuous and batch chemical processes.
However, the application of NIR to extrusion processes has been limited by the difficulty of gaining access to the material within an extruder.
To solve this problem, Axiom has introduced a diffuse reflectance probe that can be mounted in any of the 1/2-20 UNF pressure transducer fittings that are available on most polymer extruders.
Until now, NIR monitoring of polymer melts and other extrusion processes required a flow cell either at the output of an extruder or in a re-circulating loop.
While providing good spectroscopic results, this arrangement has limitations since it is only compatible with small-diameter flow paths and often requires modification of the existing equipment.
As a result, it has generally been applied only to small-scale extruders.
Previous attempts to introduce probes, directly into the body of a large-scale extruder have been prevented by the lack of suitable fittings and the fact that the penetration depth required by existing probe designs was incompatible with extrude design.
The FDR-755 probe is designed to fit the 1/2-20 UNF Dynisco-compatible fittings widely used for extruder pressure transducers.
At the same time, by using diffuse reflectance, its design has reduced the required penetration into the melt.
It is therefore compatible with any size extruder and can be quickly attached without requiring modification to existing equipment.
This makes it practical-to-use near-infrared spectroscopy for short-term analysis and troubleshooting as well as for continuous long-term polymer process monitoring.
