Most Flexible SLS Powders You Can Buy Today

Over the last few articles, we’ve talked a lot about the classics of SLS printing—PA12 for its balanced performance and precision, and PA11 for its durability and impact resistance. But now it’s time to focus on those who need something very different: true flexibility. If your application calls for soft-touch components, bendable geometries, dynamic parts, or rubber-like behavior, this article is for you.

Today, we’re exploring the world of flexible SLS powders, with a specific highlight on SLS flexible TPU, one of the fastest-growing material categories in additive manufacturing.

What Exactly Are Flexible SLS Powders?

Flexible SLS powders are materials engineered to retain elasticity after sintering. Unlike standard nylons, which are rigid, these powders create parts that can:

• bend and flex repeatedly without cracking,
• compress and spring back to shape,
• provide cushioning or shock absorption,
• mimic rubber-like properties,
• withstand strong abrasion and cyclic loading.
  
  

Yes—PA11 is naturally more flexible than PA12, but to achieve true elastomer-like performance, you need materials formulated specifically for flexibility.

Enter TPU.

What Does TPU Stand For?

TPU stands for Thermoplastic Polyurethane, a well-known elastomer used in consumer goods, footwear, automotive components, medical devices, protective gear, and countless soft-touch products.

As a powder optimized for SLS, TPU becomes an incredibly capable tool for engineers and designers. SLS flexible TPU offers:

• high elasticity,
• excellent rebound,
• strong tear resistance,
• great chemical and abrasion resistance,
• and the ability to form complex geometries—support-free.

This combination makes TPU one of the most versatile and exciting material families in powder-based 3D printing.

Why Choose Flexible TPU in SLS Instead of Other 3D Printing Technologies?

✔ No need for supports

SLS handles even the most complex elastic designs with ease.

✔ Superior mechanical consistency

Parts are strong and uniform throughout the entire volume.

✔ Better durability than flexible FDM materials

SLS TPU is significantly more robust and resistant to fatigue.

✔ Great fit for small-batch production

You can manufacture end-use flexible parts quickly and cost-effectively.

Flexible SLS materials give you the perfect blend of elastomeric performance and industrial manufacturing capability.

What 3d Printing Material Is The Most Flexible?

Below are the leading SLS flexible TPU powders dominating the market, known for their elasticity, durability, and print reliability.

1. Sinterit Flexa Performance — A True SLA Flexible TPU for Demanding Applications

If you’re looking for a SLS TPU that delivers real elasticity, durability, and rubber-like behavior, Sinterit Flexa Performance is one of the strongest choices available. Designed specifically for SLS printing on Sinterit machines, it brings impressive mechanical properties while staying easy to handle.

Why it stands out:

• Excellent flexibility and rebound: Elongation at break of 173–183% enables deep bending and stretching without tearing.
  
  
• Rubber-like feel: With a hardness of around Shore A 88, parts are soft, elastic, and durable—ideal for seals, cushions, and ergonomic components.
  
  
• High resistance to dynamic and abrasive forces: Perfect for vibration dampers, soft housings, wearables, and components exposed to repeated mechanical stress.
  
  
• Easy and cost-effective to print: No nitrogen required, and a refresh rate of ~20% keeps operating costs manageable.
  
  
• Wide application range: Excellent for footwear components, padding systems, medical orthotics, soft interfaces, and custom-fit consumer goods.
  
  

In short, Flexa Performance is a purpose-built flexible powder that transforms SLS systems into true elastomer manufacturing tools.

2. BASF Ultrasint® TPU01

One of the most widely used industrial TPU powders, trusted for its consistency and quality.

Highlights:

• Excellent elastic recovery
• Great wear and tear resistance
• Good surface finish (for an elastomer)
• Ideal for footwear, cushioning, sporting goods, and protection systems

3. EOS TPU 1301

A flexible powder with shape-memory properties and outstanding fatigue resistance.

Highlights:

• Balanced softness and tensile strength
• Supports complex lattice geometries
• Highly durable during repeated loading cycles
• Ideal for robotics, prosthetics, and ergonomic devices
  
  
  

Where Flexible SLS TPU Really Shines

Flexible SLS materials thrive in industries that require softness, safety, and comfort:

• Footwear & Wearables

Shock-absorbing midsoles, ergonomic padding, straps, and fashion tech.

• Sports Equipment

Protective gear inserts, flexible grips, cushioning layers.

• Medical Applications

Orthotic components, braces, soft patient-specific supports.

• Robotics & Automation

Soft grippers, flexible joints, vibration dampers.

• Industrial Seals & Gaskets

Custom, high-performance sealing solutions manufactured on demand.

What to Consider When Working With Flexible SLS TPU

Even though SLS TPU materials are powerful, they come with a few printing considerations:

• TPU powder can be more moisture-sensitive than PA—store it well.
  
  
• Warm printed parts are soft; let them cool fully before unpacking.
  
  
• Careful parameter tuning ensures optimal elasticity.
  
  
• Vapour smoothing can be used, but with caution—it may overly soften surfaces.
  
  

Once dialed in, though, these materials are incredibly reliable.

A Few Thoughts from the Field

Flexible TPUs are often the moment when designers and engineers realize just how far additive manufacturing can go. Suddenly, they can create cushioning structures, ergonomic shapes, complex organic forms, and rubber-like components—all without molds or compromises.

If PA12 and PA11 are the backbone of SLS, TPU is the freedom layer—allowing you to rethink what flexible products can look like and how quickly they can be produced.

FAQ – Flexible TPU in SLS Printing

What makes TPU different from rigid SLS materials like PA12 and PA11?

TPU is a true elastomer—soft, flexible, and rubber-like—while PA12 and PA11 are engineering plastics.

What does TPU stand for?

TPU stands for Thermoplastic Polyurethane.

Why choose SLS flexible TPU for your application?

Because it delivers rubber-like behavior with SLS precision, durability, and freedom of design.

Can TPU parts handle repeated bending and stretching?

Absolutely—TPU excels at fatigue resistance and elastic recovery.

Which industries benefit most from flexible SLS powders?

Footwear, wearables, medical devices, robotics, consumer goods, and industrial seals.

Is Sinterit Flexa Performance suitable for production parts?

Yes. It offers industrial-grade durability, elasticity, and consistent performance.

Are flexible SLS powders harder to print than nylons?

They require more parameter control, but once optimized, they print reliably.

Can TPU parts be post-processed?

Yes—media blasting works great. Vapour smoothing is possible but should be used carefully.

How do SLS flexible TPUs compare to flexible FDM materials?

They’re significantly stronger, more consistent, and more durable.