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Photochemical Reactions in Dialdehyde Starch
Marta Ziegler-Borowska1, Katarzyna Wegrzynowska-Drzymalska2, Dorota Chelminiak-Dudkiewicz3
1Faculty of Chemistry, Nicolaus Copernicus University in Torun, Gagarina 7, 87-100 Torun, Poland. martaz@chem.umk.pl.
Molecules (Basel, Switzerland)
|December 21, 2018
Summary
Oxidized potato and corn starch (dialdehyde starch) were studied for their stability under UV radiation. Dialdehyde corn starch showed higher photostability, influenced by bound sodium iodide(V).
Area of Science:
- Materials Science
- Polymer Chemistry
- Photochemistry
Background:
- Starch modification is crucial for developing advanced materials.
- Understanding the photostability of modified starches is essential for their application in UV-exposed environments.
- Dialdehyde starch (DAS) offers unique chemical functionalities for material design.
Purpose of the Study:
- To synthesize and characterize dialdehyde starch (DAS) from potato and corn starch.
- To investigate the photostability of DAS under UV irradiation.
- To elucidate the effect of functional group content and bound sodium iodide(V) on DAS photochemistry.
Main Methods:
- Sodium periodate oxidation of potato and corn starch.
- Characterization using chemical analysis, SEM, ATR-FTIR, contact angle, surface free energy, and XRD.
- Exposure to polychromatic UV radiation and monitoring of photochemical reactions.
- Analysis of photooxidative degradation mechanisms.
Main Results:
- Dialdehyde corn starch exhibited higher photostability than oxidized potato starch due to a greater number of functional groups.
- Bound sodium iodide(V) significantly impacted the photooxidative degradation of DAS.
- Surface properties and crystallinity were altered by oxidation and UV irradiation.
Conclusions:
- Dialdehyde corn starch is a more photostable material compared to oxidized potato starch.
- The presence of bound sodium iodide(V) plays a critical role in the photodegradation pathways of DAS.
- This study proposes a mechanism for photoinduced reactions in dialdehyde starch systems.
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