If you have ever worked with 3D printing, you know that printed objects are often quite brittle. Even when removing an item from the print bed, there is a risk of damaging it: a figurine, a spare part, or a gift that took hours to create can easily break into pieces.

This issue is especially relevant for wearable electronics, soft robotics, and medical technologies, where 3D-printed components have long remained vulnerable to breakage and material fatigue.

Problems with Traditional Elastomers

Conventional single-network elastomers—flexible polymers that can stretch and return to their original shape thanks to weak intermolecular bonds—typically operate on an “either-or” principle. If the material is resistant to breakage, it is still prone to fatigue damage under repeated stress. Conversely, if it resists fatigue well, it may fail under a strong impact or heavy stretching.

Development of a New Material

Researchers from the Swiss Federal Institute of Technology Lausanne (EPFL) have proposed a solution: a 3D-printable elastomer that is resistant both to strong impacts and to long-term wear. Their work describes a material called DNGE (double-network granular elastomers), in which rigid elastomer particles are embedded within a soft elastomer matrix. This structure effectively redistributes stress and repeatedly dissipates energy during moderate deformations, providing high fatigue resistance.

Features and Advantages of DNGE

The EPFL team had previously worked with DNGE, creating 3D-printable environments with tailored mechanical properties. Their research revealed that the granular structure of the material significantly increases its strength. This is due to mechanisms of repeated energy dissipation: the material can absorb energy multiple times without irreversible damage, thanks to its structural diversity.

Compared to similar elastomers, DNGE demonstrates three times greater fatigue resistance and up to 15 times higher strength. This is achieved by redistributing mechanical stress from the rigid particles to the soft matrix that connects them. Instead of breaking polymer bonds, the polymer chains are reorganized, reducing the risk of sudden failure.

Structural Features and Application Prospects

The granular structure of DNGE does not prevent all cracks from forming, but it forces them to pass through soft regions rather than along a straight line, lowering the likelihood of complete product failure. This approach could be valuable for soft robotics, wearable devices, and biomedicine, where modern materials are limited by trade-offs between stiffness, strength, and fatigue resistance. Using DNGE can extend product lifespan and reduce costs.

The Future of Material Development

In the future, the plan is to further improve DNGE’s durability by using biodegradable and recycled materials. This will help reduce environmental impact and make the material more accessible to laboratories equipped with commercial 3D printers, without compromising mechanical properties.