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Published on: February 6, 2016
A new self-healing epoxy with tungsten (VI) chloride catalyst
Jason M Kamphaus1, Joseph D Rule, Jeffrey S Moore
1Department of Aerospace Engineering, University of Illinois, Urbana, IL 61801, USA. kamphaus@gmail.com
Journal of the Royal Society, Interface
|June 21, 2007
Summary
Tungsten (VI) chloride (WCl6) shows promise as a cost-effective catalyst for self-healing polymers. This study demonstrates its effectiveness in restoring fracture toughness in materials, paving the way for commercial applications.
Area of Science:
- Materials Science
- Polymer Chemistry
- Catalysis
Background:
- Commercial self-healing materials require cost-effective, stable healing chemistries.
- Tungsten (VI) chloride (WCl6) is explored as a potential catalyst precursor for ring-opening metathesis polymerization.
Purpose of the Study:
- To evaluate tungsten (VI) chloride (WCl6) as a catalyst precursor for self-healing applications using exo-dicyclopentadiene (exo-DCPD).
- To assess the environmental stability and healing performance of WCl6 with different delivery methods.
Main Methods:
- Investigated the ring-opening metathesis polymerization of exo-dicyclopentadiene (exo-DCPD) catalyzed by WCl6.
- Evaluated WCl6 environmental stability across three delivery methods.
- Assessed fracture toughness recovery after crack propagation.
Main Results:
- Both as-received and recrystallized WCl6 achieved nearly complete fracture recovery at 12wt% loading in self-activated tests.
- In situ healing using microencapsulated exo-DCPD with 15wt% WCl6 yielded approximately 20% healing efficiency.
Conclusions:
- Tungsten (VI) chloride (WCl6) is a viable and effective catalyst precursor for self-healing polymers, demonstrating significant fracture toughness recovery.
- Further optimization of in situ delivery methods is needed to improve healing efficiencies for broader applications.
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