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09:37
Fabrication of a Bioactive, PCL-based "Self-fitting" Shape Memory Polymer Scaffold
Published on: October 23, 2015
Post-Polymerization Crosslinked Polyurethane Shape-Memory Polymers.
1School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332.
Journal of Applied Polymer Science
|May 17, 2011
Summary
Novel urethane shape-memory polymers (SMPs) offer advanced processing capabilities. These post-polymerization crosslinked materials exhibit excellent mechanical properties and shape recovery, making them ideal for industrial applications, including medical devices.
Area of Science:
- Materials Science
- Polymer Chemistry
Background:
- Traditional shape-memory polymers (SMPs) require one-step polymerization.
- Post-polymerization crosslinking offers enhanced processing flexibility.
Purpose of the Study:
- To synthesize and characterize novel urethane SMPs via post-polymerization crosslinking.
- To evaluate their processability and thermo-mechanical properties for industrial applications.
Main Methods:
- Synthesis of linear, olefinic urethane polymers.
- Thermoplastic melt processing followed by thermal or electron beam crosslinking.
- Characterization using solvent swelling, DSC, DMA, tensile testing, and shape recovery analysis.
Main Results:
- Successful synthesis of processable urethane SMPs with tunable properties.
- Demonstrated evidence of chemical crosslinking and outstanding mechanical performance.
- Achieved tailorable transitions (25-80°C), high recoverable/failure strains, and rapid shape recovery (<12s at 37°C).
Conclusions:
- Post-polymerization crosslinked urethane SMPs are highly processable and industrially relevant.
- These materials possess excellent thermo-mechanical properties suitable for complex applications.
- One polyurethane was selected for a complex medical device design, highlighting practical utility.
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