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Analysis and Specification of Starch Granule Size Distributions
Published on: March 4, 2021
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Starch carboxymethylation by reactive extrusion: Reaction kinetics and structure analysis
Romain Milotskyi1, Christophe Bliard1, Dominique Tusseau2
1Institut de Chimie Moléculaire de Reims, ICMR, CNRS UMR 7312, URCA, B18, UFR SEN, Moulin de la Housse, Chemin des Roulliers, BP 1039, F 51 687, Reims, Cedex 2, France.
Carbohydrate Polymers
|May 27, 2018
Summary
Reactive extrusion (REX) offers a highly efficient method for starch carboxymethylation, achieving 65% reaction efficiency in just 5 minutes. This novel approach significantly accelerates reaction kinetics compared to traditional solution-based methods.
Area of Science:
- Polymer Chemistry
- Materials Science
- Biomaterials
Background:
- Starch modification is crucial for developing new biomaterials.
- Traditional carboxymethylation methods in solution are often slow and inefficient.
- Reactive extrusion (REX) presents a promising alternative for polymer modification.
Purpose of the Study:
- To investigate the efficiency and kinetics of carboxymethylation of plasticized starch using reactive extrusion (REX).
- To characterize the reaction products and understand the influence of key reaction parameters.
- To explore the regioselectivity and multi-substitution patterns in REX-modified starch.
Main Methods:
- Carboxymethylation of plasticized starch via reactive extrusion (REX).
- Characterization of reaction products using Nuclear Magnetic Resonance (NMR) spectroscopy and high-performance liquid chromatography (HPLC).
- Investigation of parameters: plasticizer amount, reagent stoichiometry, and reaction time.
Main Results:
- Achieved up to 65% reaction efficiency (RE) in a single step within 5 minutes.
- Demonstrated reaction kinetics approximately 100 times faster than solution-based methods.
- Obtained a degree of substitution (DS) of 2.1 in 3 steps with observed regioselectivity (C-2 > C-6 > C-3) and deviation from the Spurlin model.
- Analyzed multi-substituted anhydroglucose units (AGU) and identified different substitution patterns based on starch source.
Conclusions:
- REX is a highly efficient and rapid technique for starch carboxymethylation.
- The method allows for controlled modification, yielding specific degrees of substitution and regioselectivity.
- REX offers a versatile platform for producing novel starch derivatives with tailored properties.
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