Nanocomposite Polymer Creates Ultra-Thin Electromagnetic Shields

A research team has developed a shielding material thinner than a human hair that blocks nearly all electromagnetic interference and a significant portion of neutron radiation.

At the heart of the breakthrough is the creation of a nanocomposite which combines carbon nanotubes for electromagnetic shielding with boron nitride nanotubes for neutron absorption. The result is a polymer film that is not only highly effective but also stretchable, lightweight, and functional across extreme temperatures.

More importantly, it can be stretched and shaped like rubber, and even 3D-printed into complex structures—something which manufacturers will recognise as a clear entry point onto the market.

Traditionally, shielding has always come with trade-offs. If you want protection, you typically accept weight, rigidity, and complexity. In aerospace, that means higher fuel costs, in electronics, it means design constraints, and in medical and nuclear environments, it often means bulky, expensive systems.

But by combining multiple shielding functions from nanomaterials into a single, ultra-thin material, manufacturers can reduce layers, simplify assemblies, and rethink product design entirely. Less material, fewer components, and lower weight all translate directly into cost savings alongside performance gains.

The Polymer Angle Everyone Misses

Most coverage of this development has focused on the nanotubes, but commercially, they are only half the story.

The real enabler is the polymer which provides the flexibility, processability, and scalability that turn a lab material into something manufacturers can actually use. In this case, it is a polydimethylsiloxane (PDMS) matrix without which the nanotubes would remain difficult to handle, difficult to shape, and difficult to integrate into products. Even the honeycomb shape the polymer is formed into added “up to 15% better shielding performance than flat materials of the same thickness.”

This is not a nanotechnology breakthrough; it is a nanocomposite formulation breakthrough.

“This material represents a completely new concept in shielding technology,” notes Dr Joo Yong-ho, who led the research at the Extreme Environment Shielding Materials Research Center of the Korea Institute of Science and Technology (KIST). “It is as thin as tape and as flexible as rubber, yet simultaneously blocks both electromagnetic waves and radiation.”

The discovery has now been published in the journal Advanced Materials, where it is noted that, “The resulting neat composites demonstrate EMI shielding effectiveness exceeding 50 dB and neutron attenuation coefficient of 1.27 mm−1 (equivalent to ∼72% attenuation at a mm thickness) at thicknesses on the order of tens of micrometers, where the polymer composites exhibit the shielding effectiveness up to 23 dB at sub-millimeter thicknesses while maintaining mechanical resilience under cyclic strain and thermal extremes (–196°C to 250°C).”

The research also highlights the multi-purpose advantages of using nanoadditives in polymers. In this latest development, carbon nanotubes (CNTs), which are highly conductive, absorb and reflect electromagnetic waves, while boron nitride nanotubes (BNNTs), rich in boron, effectively capture neutrons. It sounds like a neat division of labour—and scientifically, it is, but for manufacturers, it is a way to add value to polymer products.

“As the two materials naturally form a "shell structure" in which they envelop each other, a single film is now capable of simultaneously blocking both types of hazards,” explains the online scientific journal Phys.org. “As a result, the material achieves performance that blocks 99.999% of electromagnetic waves and reduces neutrons by approximately 72%, even at a thickness thinner than a human hair.”

As with most advanced materials, the first real applications will not be in mass markets.

Instead, expect early adoption in sectors where performance outweighs cost: space systems, defence electronics, nuclear environments, and high-end medical devices. In these areas, reducing weight or improving shielding efficiency is not a nice-to-have—it is mission-critical.

However, nanocomposite polymers like this open the door to a new generation of products, such as lightweight shielding integrated directly into structural components, flexible protection layers for wearable systems, and multifunctional composites that combine mechanical strength with electromagnetic and radiation resistance.

Perhaps more importantly, nanocomposites point towards a broader change in polymer markets. Modern manufacturing materials are no longer passive but are instead being engineered as systems with performance designed at multiple levels—from the nanoscale to the final geometry.

In many ways, this means that the value for polymer manufacturers is no longer just in supplying advanced fillers or base plastics. It sits in the ability to combine formulation, processing, and structural design into a functional product. A market where companies that control the chain (from dispersion of nanotubes to printable formulations to engineered geometries) will be the ones capturing improved margins and new customers.

The Know-How Gap in Nanocomposites

There’s a bit of an open secret in the polymer industry, with plenty of companies keen to get into nanomaterials but far fewer actually knowing what to do with them once they arrive.

On paper, it sounds simple enough—mix nanotubes into a polymer and you’re done. In reality, it’s anything but. Getting a clean dispersion, keeping the nanotubes functional, and making sure the final material still behaves properly is where things start to fall apart. Then you add requirements like printability, mechanical strength, and reliable shielding performance, and it quickly becomes a different kind of problem altogether.

That’s the real constraint. It’s not sourcing the materials—it’s making them work.

The gap between nanomaterials and real-world polymer processing is still wide, and closing it isn’t just a technical exercise. It’s what turns promising materials into something companies can actually sell. To learn more about how Polymer Nano Centrum (who support this website) can improve plastics, epoxy resins, and polymer coatings, visit: Polymer Nano Centrum or contact info@polymernanocentrum.cz

Photo credit: Vecteezy, Vecteezy, Vecteezy, Vecteezy, & Vecteezy.