Thermo-hydration driven shape-memory hydrogel with functional cellulose for smart vascular stent
Yulei Li1, Guohua Miao1, Cuiping Wang1
1Beijing Key Laboratory of Lignocellulosic Chemistry, Engineering Research Center of Forestry Biomass Materials and Energy, Ministry of Education, Beijing Forestry University, Beijing, 100083, China.
International Journal of Biological Macromolecules
|October 12, 2025
Summary
Researchers developed a novel shape memory polymer (SMP) composite that effectively recovers its permanent shape at physiological temperature (37°C). This breakthrough offers promising advancements for biodegradable vascular stents and other biomedical applications.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Nanotechnology
Background:
- Shape memory polymers (SMPs) are being explored for vascular stent applications.
- A key challenge is achieving shape recovery at physiological temperature (37°C).
- Water's influence on polymer intermolecular forces can be leveraged for temperature-responsive materials.
Purpose of the Study:
- To develop a novel SMP that exhibits shape recovery at physiological temperature (37°C) in a thermo-hydration environment.
- To synthesize and characterize a waterborne polyurethane/cellulose nanocrystal composite (WPCx) for enhanced shape memory properties.
- To investigate the role of cellulose nanocrystals (CNCs) in modulating the thermo-responsive behavior of the SMP.
Main Methods:
- Solvent-assisted self-assembly was used to synthesize WPCx composites with varying CNC content (x).
- Molecular dynamics simulations were employed to understand the interfacial interactions between CNCs and waterborne polyurethane (WPU).
- Shape recovery efficiency, mechanical properties, and hydrophilicity were evaluated.
Main Results:
- The WPCx composite demonstrated programmable shape recovery at 37°C with 95.2% efficiency.
- Molecular dynamics simulations indicated that CNC-WPU interactions shift from cohesive attraction to steric repulsion under thermo-hydration conditions.
- CNC dispersion enhanced hydrophilicity and accelerated water diffusion kinetics.
Conclusions:
- The developed WPCx composite exhibits excellent shape memory capabilities, mechanical properties, and biocompatibility.
- This material is suitable for fabricating vascular stents and has potential for other biomedical applications.
- The study highlights the effectiveness of thermo-hydration-responsive SMPs for physiological temperature applications.
