Physical Organohydrogels With Extreme Strength and Temperature Tolerance
Jing Wen Zhang1,2, Dian Dian Dong1,2, Xiao Yu Guan1,2
1College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi'an, China.
Frontiers in Chemistry
|March 27, 2020
Summary
This study presents tough organohydrogels made from Europium (Eu)-alginate/polyvinyl alcohol (PVA) that remain flexible and strong at extremely low temperatures, expanding the use of soft materials in harsh environments.
Area of Science:
- Materials Science
- Polymer Chemistry
- Soft Matter Physics
Background:
- Soft materials like hydrogels often lose integrity at subzero temperatures.
- Developing gels with extreme temperature tolerance is crucial for specialized applications.
Purpose of the Study:
- To synthesize and characterize physically crosslinked Europium (Eu)-alginate/polyvinyl alcohol (PVA) organohydrogels.
- To evaluate their performance under extreme subzero conditions, focusing on mechanical properties and shape recovery.
Main Methods:
- Organohydrogels synthesized by replacing water in hydrogel networks with cryoprotectants (ethylene glycol, glycerol, d-sorbitol).
- Mechanical testing (stress, strain) and shape recovery assessment at temperatures as low as -45°C.
Main Results:
- Organohydrogels demonstrated no freezing and maintained high stress (5.62 MPa) and strain (7.63) at -45°C.
- Enhanced mechanical properties attributed to synergistic hydrogen and coordination bonds, and dense polymer networks.
- Materials showed excellent shape recovery after bending, folding, and twisting at low temperatures.
Conclusions:
- Physically crosslinked Eu-alginate/PVA organohydrogels exhibit exceptional toughness and wide temperature tolerance.
- These materials offer a promising solution for applications requiring robust soft materials in harsh, cold environments.
