Triple network hydrogels (TN gels) prepared by a one-pot, two-step method with high mechanical properties
Xiangong Wang1, Fang Zhao1, Bo Pang1
1Key Laboratory of Special Functional Aggregated Materials, Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University Jinan 250100 P. R. China fsy@sdu.edu.cn qinxvping@sdu.edu.cn.
RSC Advances
|May 11, 2022
Summary
Novel triple-network hydrogels combining poly(vinyl alcohol) (PVA) with polyacrylamide/polyacrylic acid (PAM/PAA) exhibit high strength and tunable swelling. These advanced biomaterials utilize sacrificial bonds for energy dissipation and self-reformation.
Area of Science:
- Materials Science
- Polymer Chemistry
- Biomaterials Engineering
Background:
- Hydrogels are versatile materials with applications in various fields.
- Developing hydrogels with enhanced mechanical properties and controlled swelling remains a key challenge.
- Poly(vinyl alcohol) (PVA), polyacrylamide (PAM), and polyacrylic acid (PAA) are common polymers used in hydrogel fabrication.
Purpose of the Study:
- To synthesize novel polyacrylamide/polyacrylic acid/poly(vinyl alcohol) (PAM/PAA/PVA) triple-network (TN) hydrogels.
- To investigate the mechanical properties, swelling behavior, and self-healing capabilities of the developed TN hydrogels.
- To explore the potential of these TN hydrogels for biomaterial applications.
Main Methods:
- In situ polymerization combined with repeated freezing-thawing (F-T) cycles were employed for hydrogel synthesis.
- The weight ratios of calcium chloride (CaCl2) and PVA were varied to tune hydrogel properties.
- Mechanical testing (compressive and stretching stress) and swelling tests were conducted.
Main Results:
- The synthesized PAM/PAA/PVA TN hydrogels demonstrated high mechanical strength, with compressive stress reaching 11 MPa and stretching stress up to 0.8 MPa.
- The hydrogels exhibited moderate swelling ability, which could be adjusted by varying CaCl2 and PVA content.
- The PAA and CaCl2 coordination network acted as sacrificial bonds, dissipating energy during mechanical loading and reforming upon load release.
Conclusions:
- The developed PAM/PAA/PVA TN hydrogels possess excellent mechanical properties and tunable swelling.
- The sacrificial bond mechanism contributes to the energy dissipation and potential self-healing characteristics.
- These TN hydrogels show promise for various biomaterial applications due to their robust and adaptable nature.
