Ice-Templated and Cross-Linked Xanthan-Based Hydrogels: Towards Tailor-Made Properties
Irina Elena Raschip1, Nicusor Fifere1, Maria Marinela Lazar1
1"Petru Poni" Institute of Macromolecular Chemistry, Grigore Ghica Voda Alley 41A, 700487 Iasi, Romania.
Gels (Basel, Switzerland)
|July 28, 2023
Summary
This study improved xanthan gum (XG) films for food packaging by using cryogelation and cross-linking agents. The resulting XG cryogels show enhanced mechanical properties and stability, particularly when cross-linked with 1,4-butanediol diglycidyl ether.
Area of Science:
- Materials Science
- Polymer Chemistry
- Biomaterials Engineering
Background:
- Polysaccharides like xanthan gum (XG) are promising for food packaging due to film-forming properties.
- XG films have limitations: poor mechanical strength and high hydrophilicity, affecting moisture stability and handling.
- Cross-linking is explored to enhance XG properties for advanced applications.
Purpose of the Study:
- To stabilize a xanthan gum (XG) matrix through cross-linking.
- To prepare XG-based cryogels with improved physicochemical properties.
- To evaluate the impact of different cross-linkers and ratios on XG cryogel characteristics.
Main Methods:
- Cryogelation technique used for XG matrix stabilization below freezing point.
- Cross-linking agents employed: glycerol diglycidyl ether, 1,4-butanediol diglycidyl ether, and epichlorohydrin.
- Characterization methods included FTIR, SEM, AFM, swelling kinetics, and uniaxial compression tests.
Main Results:
- XG-based cryogels were successfully prepared in various forms (microspheres, monoliths, films).
- Characterization revealed a heterogeneous morphology with interconnected pores; pore size varied with cross-linker type and ratio.
- Cryogels cross-linked with 1,4-butanediol diglycidyl ether demonstrated superior elasticity, withstanding high deformations.
Conclusions:
- Cryogelation is an effective, eco-friendly method for enhancing XG properties.
- Cross-linking significantly improves the mechanical stability and reduces the hydrophilicity of XG materials.
- Tailoring cross-linker choice and concentration allows for controlled modification of XG cryogel properties for specific applications.
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