On-Line Monitoring of Molecular Weight Using NIR Spectroscopy in Reactive Extrusion Process

Reactive extrusion consists in using an extruder as a continuous chemical reactor. It is not a recent process, but it has been rapidly developed during the last thirty years and is more and more used today for the chemical modification of existing polymers. Among the various extrusion systems (single screw extruders, counter- and corotating twin-screw extruders, co-kneaders), the corotating twin-screw extruders are today the most widely used in reactive extrusion. After a presentation of the main advantages and drawbacks of the reactive extrusion, we will describe the way to control the process through on-line and in-line monitoring. Then, a modelling approach based on continuum mechanics will be presented, followed by an example of industrial applications of this particular process.

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Polysaccharides and lignin based hydrogels with potential pharmaceutical use as a drug delivery system produced by a reactive extrusion process

International Journal of Biological Macromolecules ◽

10.1016/j.ijbiomac.2017.06.037 ◽

2017 ◽

Vol 104 ◽

pp. 564-575 ◽

Cited By ~ 24

Author(s):

Wissam Farhat ◽

Richard Venditti ◽

Nathalie Mignard ◽

Mohamed Taha ◽

Frederic Becquart ◽

...

Keyword(s):

Drug Delivery ◽

Drug Delivery System ◽

Delivery System ◽

Reactive Extrusion ◽

Extrusion Process ◽

Reactive Extrusion Process

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On-Line Rheometry for Twin-Screw Extrusion (Along the Extruder) and its Applications

Applied Rheology ◽

10.1515/arh-2002-0002 ◽

2002 ◽

Vol 12 (1) ◽

pp. 18-24 ◽

Cited By ~ 8

Author(s):

J. M. Maia ◽

O. S. Carneiro ◽

A. V. Machado ◽

J. A. Covas

Keyword(s):

Reactive Systems ◽

Reactive Extrusion ◽

Extrusion Process ◽

Experimental Conditions ◽

Capillary Rheometry ◽

Existing Problems ◽

Twin Screw ◽

On Line ◽

Dispersive Mixing ◽

Carbon Fibre Composites

Abstract Due to a number of practical difficulties, both in- and on-line measurements of the rheological properties of complex systems during extrusion are usually performed at the end of the extruder, under very specific experimental conditions. This makes this type of instruments more useful for quality control than for process optimisation, since information about the influence of the geometry and/or processing conditions on the evolution of the material characteristics inside the extruder is not easily gathered. Recently, however, the authors have developed an on-line capillary rheometry system that overcomes most of the existing problems and allows small amounts of sample to be tested in very near real time, along the extruder. The present work aims at illustrating the usefulness of this concept for the study of physical compounding processes and some reactive systems. Two very different systems will be used for that purpose: a reactive extrusion process (the peroxide-induced thermal degradation of polypropylene) and the dispersive mixing involved in the preparation of thermoplastic/carbon fibre composites.

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