Flax-Glass Fiber Reinforced Hybrid Composites Exposed to a Salt-Fog/Dry Cycle: A Simplified Approach to Predict Their
Luigi Calabrese1, Dionisio Badagliacco2, Carmelo Sanfilippo2
1Department of Engineering, University of Messina, Contrada Di Dio (Sant'Agata), 98166 Messina, Italy.
Polymers
|June 10, 2023
Summary
Hybridizing flax and glass fibers in composites enhances durability against humid conditions. Outer glass layers protect inner flax, improving performance and extending service life for various applications.
Area of Science:
- Materials Science
- Composite Materials Engineering
Background:
- Natural fibers are gaining attention for composites but face durability issues in humid environments.
- Synthetic fibers remain dominant due to superior performance and longevity.
- Developing durable natural fiber composites is crucial for sustainable material applications.
Purpose of the Study:
- To investigate the impact of humid/dry cycles on flax and glass fiber reinforced epoxy laminates.
- To assess the performance of a glass-flax hybrid composite compared to pure flax and glass composites.
- To evaluate the protective effect of glass fibers on flax fibers during environmental exposure.
Main Methods:
- Composites were exposed to salt-fog (15 or 30 days) followed by dry conditions (21 days).
- Mechanical responses of flax, glass, and glass-flax hybrid composites were analyzed.
- A theoretical pseudo-second-order model was developed and validated against experimental data.
Main Results:
- Glass fibers significantly stabilized mechanical performance during humid/dry cycling.
- Hybridization with outer glass layers protected inner flax from degradation.
- Composites showed performance recovery during the dry phase, with good model agreement.
Conclusions:
- Tailored hybridization of natural and glass fibers extends the service-life of composites in discontinuous humid conditions.
- Glass-flax hybrid composites are suitable for indoor and outdoor applications.
- The proposed model accurately predicts composite performance recovery.
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