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Kinetics of elastic recovery in roll compaction
Martin Lück1, Stefan Klinken-Uth1, Peter Kleinebudde1
1Heinrich Heine University Düsseldorf, Faculty of Mathematics and Natural Sciences, Institute of Pharmaceutics and Biopharmaceutics, Universitaetsstrasse 1, 40225 Düsseldorf, Germany.
International Journal of Pharmaceutics: X
|December 5, 2024
Summary
Elastic recovery in roll compaction was studied using in-line measurements. Increasing compaction force accelerated recovery, while roll speed had minimal impact unless brittle fillers were present.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
- Chemical Engineering
Background:
- Elastic recovery is crucial in tableting but understudied in roll compaction.
- Existing data on elastic recovery in roll compaction is limited.
- Roll compaction is a key process in pharmaceutical manufacturing.
Purpose of the Study:
- To investigate the kinetics of elastic recovery during roll compaction.
- To determine the effects of compaction force and roll speed on elastic recovery.
- To characterize relaxation times in roll compaction.
Main Methods:
- Utilized an in-line laser triangulation technique for measurements.
- Measured elastic recovery at different positions within roll rotation and over time.
- Analyzed pure microcrystalline cellulose and two placebo powder blends.
Main Results:
- Elastic recovery kinetics were modeled using two exponential functions: a fast and a slow phase.
- Increased compaction force accelerated both fast and slow elastic recovery phases.
- Roll speed influenced elastic recovery kinetics only when brittle fillers were included.
Conclusions:
- Established the first kinetic characterization of elastic recovery in roll compaction.
- Demonstrated the significant impact of compaction force on elastic recovery.
- Highlighted the role of material properties (brittle fillers) in modulating roll compaction behavior.
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