Recycled Nylon vs. Recycled Polyester: Which is the Best Fabric for Sustainable Swimwear?

The warmth of the sun on your skin and the rhythm of the waves—nothing compares to a perfect beach day. But as sustainability becomes a global priority, even our swimwear choices carry environmental weight.

The fashion industry is embracing a sustainable revolution, and swimwear brands are leading the change—shifting from virgin plastics to innovative recycled fabrics.

Among the most popular eco-friendly materials, recycled nylon and recycled polyester stand out for their performance and environmental benefits.

So, which is the best choice for sustainable swimwear? This guide explores recycled nylon vs. recycled polyester—their differences, advantages, and which fabric suits your swimwear goals best.

What is Recycled Nylon?

Recycled nylon is often considered the premium choice in the sustainable swimwear world. It’s known for its incredibly soft feel and superior stretch.

How It’s Made: Recycled nylon is sourced from a combination of pre- and post-consumer waste. This includes materials like discarded fishing nets (known as “ghost nets”), fabric scraps from mills, and old industrial carpets.

1. Waste materials are collected and rigorously cleaned.

2. Through a sophisticated chemical recycling and purification process, the nylon waste is broken down to its original molecular level. This is called depolymerization.

3. These molecules are then re-polymerized to create brand-new nylon fibres that are chemically identical to virgin nylon.

The gold standard for recycled nylon is ECONYL®. Their closed-loop regeneration process can be repeated infinitely without any loss in quality, turning a linear waste problem into a circular solution.

Pros of Recycled Nylon for Swimwear:

• Unmatched Softness & Comfort: Recycled nylon has a silky-smooth, luxurious feel that is exceptionally comfortable against the skin.
  
• Superior Stretch & Recovery: Nylon is famous for its elasticity. It offers a form-fitting, flattering silhouette that moves with your body and snaps back into shape.
  
• Excellent Strength: Despite its softness, nylon is an incredibly strong and resilient fibre, resistant to abrasion and pilling.
  
• Circular Potential: High-quality recycled nylon like ECONYL® is produced through a process that allows it to be infinitely recycled, creating a truly circular economy.
  

Cons of Recycled Nylon for Swimwear:

• Higher Cost: The complex chemical regeneration process is more energy-intensive and expensive than mechanical recycling, which translates to a higher price tag for the final product.
  
• Slightly Less Chlorine Resistant: While still durable, nylon can be slightly more susceptible to degradation from chlorine and sunlight over time compared to polyester. Proper care is essential.

What is Recycled Polyester?

Recycled polyester, often referred to as rPET, is the most common recycled fabric on the market. Its production process is a modern marvel of recycling.

How It’s Made: The primary source for rPET is post-consumer plastic bottles.

1. Used PET bottles (like water and soda bottles) are collected, sterilized, and sorted.
2. They are then crushed into small plastic flakes.
3. These flakes are melted down and extruded through tiny holes to form long, fine threads of yarn.
4. This yarn is then spun, woven, and finished into the fabric we know and love.

The most recognized brand in this space is REPREVE®, which transforms billions of plastic bottles into high-performance textiles used by many leading swimwear brands.

Pros of Recycled Polyester for Swimwear:

• Exceptional Durability: Polyester is a workhorse fabric. It’s highly resistant to stretching and shrinking, and it holds up remarkably well against the harsh effects of chlorine and UV radiation.
  
• Vibrant Colour & Print: The fabric’s fibres hold dye exceptionally well, meaning prints stay sharp and colours remain vibrant season after season.
  
• Quick-Drying: Polyester has low moisture absorbency, allowing it to dry very quickly—a huge plus for swimwear.
  
• Cost-Effective: The well-established recycling infrastructure for PET bottles generally makes recycled polyester a more affordable option than recycled nylon.
  

Cons of Recycled Polyester for Swimwear:

• Less Luxurious Feel: While technology has improved immensely, recycled polyester can sometimes feel slightly less soft and supple against the skin compared to high-quality nylon.
  
• Mechanical Recycling: Most rPET is made through mechanical recycling. This process, while effective, can slightly weaken the plastic’s integrity over successive recycling cycles, meaning it’s not infinitely recyclable.
  

Recycled Nylon vs. Recycled Polyester

To make it easier, let’s compare them across the most important attributes for swimwear.

Property	Recycled Nylon	Recycled Polyester
Source	Post-consumer waste (e.g., fishing nets, fabric)	Post-consumer waste (e.g., plastic bottles)
Durability	Very Good. Strong and abrasion-resistant, but can be slightly more sensitive to chlorine.	Excellent. Highly resistant to chlorine, UV rays, and pilling. Holds shape well.
Stretch & Fit	Excellent. Superior four-way stretch for a second-skin, body-hugging fit.	Good. Offers decent stretch, often blended with elastane for performance.
Drying Speed	Very Good. Dries quickly, but can hold slightly more moisture than polyester.	Excellent. Hydrophobic fibres dry very quickly.
Colour & Print	Very Good. Takes dye well for rich, beautiful colours.	Excellent. Holds vibrant colours and sharp prints exceptionally well.
Moisture Wicking	Excellent moisture-wicking properties	Moderate moisture-wicking ability
Chlorine Resistance	Moderate	Excellent chlorine resistance
UV Resistance	Moderate	Excellent UV resistance
Cost	Relatively high cost	More economical
Best Use	Swimwear requiring elasticity and durability	Swimwear for comfort and sun protection

Which is Truly More Eco-Friendly?

This is the big question, and the answer is nuanced.

Source Material:

Recycled polyester tackles the massive global issue of single-use plastic bottles. REPREVE® provides a tangible solution for this visible waste stream.

Recycled nylon, particularly ECONYL®, addresses a different but equally critical problem: ocean plastic and industrial waste. Removing ghost nets saves marine life and cleans our seas. The story of turning ocean waste into beautiful swimwear is powerful and compelling.

Recycling Process:

The chemical regeneration of ECONYL® is a game-changer. By returning the nylon to its original chemical state, it creates a product with zero loss in quality. This “closed-loop” system is the pinnacle of circularity.

Recycled polyester’s mechanical process is less energy-intensive upfront but can result in a fibre that degrades slightly with each cycle.

The Microplastic Issue:

It’s important to acknowledge that both recycled nylon and recycled polyester are synthetic fabrics that can shed microplastic fibres when washed. These tiny plastic particles can enter our waterways. To mitigate this, we can:

• Wash swimwear less frequently.
  
• Hand wash in cold water whenever possible.
  
• Use a washing bag like a Guppyfriend or a Cora Ball, which is designed to capture microfibres.
  

Which Recycled Fabric Should You Choose?

There is no single “best” choice—it depends entirely on your priorities.

Choose Recycled Polyester if:

• You are looking for a high-performance, athletic swimsuit.
  
• You prioritize extreme durability against chlorine and sun.
  
• You love vibrant, complex prints that won’t fade.
  
• You are looking for a more budget-friendly sustainable option.

Choose Recycled Nylon if:

• You prioritize a luxurious, buttery-soft feel and supreme comfort.
  
• You want the best possible fit with superior stretch and shape retention.
  
• You are invested in the concept of a truly circular economy and infinite recyclability.
  
• You are willing to invest in a premium, long-lasting garment.

Conclusion

The rise of recycled fabrics in swimwear is a monumental step forward for sustainable fashion. Whether you choose a swimsuit made from recycled plastic bottles (polyester) or one crafted from regenerated fishing nets (nylon), you are making a positive choice. You are diverting waste, conserving resources, and supporting brands that are committed to protecting our planet.

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