When Kevlar gets wet, several things can happen, though it generally remains functional. However, there are some important considerations about how water affects Kevlar's performance and durability:

1. Absorption of Moisture

• Water Absorption: Kevlar is a hydrophilic (water-attracting) material, meaning it absorbs moisture over time. While it doesn’t absorb water as much as some other fibers, such as cotton, it can still retain moisture when exposed to water.
• Weight Increase: When Kevlar absorbs water, it increases in weight. This can make the material feel heavier, especially in the case of protective gear like bulletproof vests. In certain situations, this added weight can affect comfort, performance, and maneuverability.

2. Potential Impact on Performance

• Decreased Efficiency: Water absorbed by Kevlar fibers can slightly reduce the material’s ability to absorb impact or perform at its best. In high-performance applications, such as ballistic protection, moisture can slightly affect the strength and resilience of Kevlar, though it typically doesn’t cause significant performance degradation in the short term.
• Reduced Flexibility: Kevlar’s flexibility may be reduced when wet, making it less comfortable to wear, especially for long periods. The material may stiffen when exposed to moisture, impacting the overall fit of body armor, for example.

3. Long-Term Durability

• Possible Fiber Degradation: Although Kevlar is generally resistant to chemicals and environmental factors, prolonged exposure to water (especially saltwater or highly chlorinated water) can degrade the fibers over time. This is particularly true if the material is not properly dried and maintained after being exposed to moisture.
• UV Sensitivity: While moisture itself doesn’t damage Kevlar fibers as much as direct sunlight, water can sometimes promote the degradation of the material when exposed to UV light. Moisture may speed up the breakdown of the polymeric bonds in the fibers, weakening the material over time.

4. Effect on Ballistic Vests

• Impact on Bulletproof Vests: Bulletproof vests often use Kevlar as a primary material, and while the vest will still offer some protection when wet, wetting can compromise its effectiveness. In particular, if the vest is not dried properly, the fibers may not perform at their highest level. However, ballistic testing standards take into account some environmental factors, so a wet Kevlar vest will still provide protection, but it may not be as effective as a dry one.
• Waterproof Coatings: Some Kevlar-based vests are treated with waterproof coatings to prevent moisture absorption. These treated vests tend to fare better in wet conditions, keeping their performance intact.

5. Drying and Maintenance

• Proper Drying: If Kevlar gets wet, it’s important to dry it properly to prevent any long-term damage. Air-drying is the best method. Avoid using direct heat sources (such as a dryer or radiator), as excessive heat can cause the fibers to lose their structural integrity.
• Storage Considerations: If Kevlar remains wet for long periods without being dried properly, it can develop mildew or other issues due to prolonged moisture exposure. Therefore, it’s crucial to store any Kevlar gear in a well-ventilated area to avoid moisture buildup and ensure longevity.

6. Effect on Kevlar Clothing

• Kevlar is also used in clothing (e.g., motorcycle jackets, gloves, pants) due to its durability and cut-resistance. When these clothing items get wet, similar issues may arise, including weight increase, reduced flexibility, and potential long-term degradation if not cared for properly. Just like with bulletproof vests, proper drying and care are essential to maintain their protective qualities.

Conclusion

Kevlar does not suffer immediate and drastic consequences when it gets wet, but water absorption can lead to increased weight, slightly reduced performance, and potential long-term degradation if not properly maintained. In military, law enforcement, and personal protection applications, it is recommended to keep Kevlar gear dry when possible and to ensure proper care and drying to maintain its effectiveness.