EMI Shielding with Plastic Compounds


Electronic devices are getting smaller, but their feature lists are ever expanding. The complexity of devices acts as a cause for various electromagnetic interference (EMI) problems. Against this backdrop, EMI shielding has emerged as an essential element of product design. In an electromagnetic environment, there can be more than one electrical appliance. They influence one another and cross talk among themselves. This mutual interference badly affects the functionalities of devices working in the same environment. EMI shields help to make appliances immune to such disturbances, and enable them to work efficiently. They protect sensitive components from incoming EMI on the one hand and prevent these components from emitting excessive magnetic waves on the other hand so that they do not end up damaging other susceptible equipment in the surrounding area.


A variety of items have traditionally been used for electromagnetic shielding purposes. These included sheet metal, metal foam, and metal screen among the others. All these shielding equipment have one pain point – the holes.  Any hole in a shield has to be smaller than the wavelength of the radiations. Otherwise, the enclosed space will not be able to fully block the radiations coming from the outside environment. Thanks to this drawback, designers are increasingly turning to other more viable electromagnetic shielding materials, especially the thermoplastic compounds. Thus, recent years have witnessed a tremendous surge in the use of plastic resins that come complete with conductive coatings or fibers. These EMI/RFI resistant compounds are highly reliable and offer tremendous value to applications that have to comply with stringent electromagnetic compatibility rules. Undeniably a better choice than metals, unfilled resins, or coatings, these specially created compounds give designers and manufacturers tremendous flexibility with regard to the design process.

Physical Features of Thermoplastic Compounds

Thanks to the increasingly stringent government regulations on both emission and immunity, manufacturers of electronic goods and product designers are required more than ever to integrate shielding equipment into their product architectures. Thermoplastic enables them to meet these regulations cost-effectively.

Generally, materials such as carbon fiber, stainless steel fiber, or nickel-coated carbon fiber are used in a thermoplastic matrix to provide effective shielding. Reinforced with an array of chemicals such as flame retardant additives, wear additives, and colorants, these compounds generally come with flame retardant qualities.  These compounds are also able to meet a variety of unique application requirements.

The shielding efficiency of these materials depend on a combination of factors such as the thickness, conductivity level, and dispersion of conductive additive used in the compound. Besides shielding, these compounds can provide some electrostatic discharge (ESD) control to the applications that need it.


Besides electronics, these EMI Shielding compounds are suitable for use in a variety of markets, including the electrical, automotive, energy, and healthcare sectors.

Weight Reduction

The designers are always on the lookout for EMI materials that do not unnecessarily add to the weight. Thermoplastic compounds provide you just that.

Design flexibility                                                                

How do you seamlessly integrate the shield into a product without affecting its functionality? This question often throws product designers off-balance. Polymer substances give designers a lot of flexibility by providing many fastening options. They also facilitate complex contours and part consolidation.

Cost Effectiveness

These flexible materials can be used in higher volumes and can thus help to reduce assembly costs.

Powerful Physical Properties

The thermoplastic compounds are inherently corrosion-resistant, which increases their longevity. In other words, these materials continue providing protection to the electronics for a long time.


Thanks to their flexibility, these compounds are ideal for making gaskets between mated parts.

The electronics industry is evolving at a fast pace. Under this circumstance, product designers are opting for newer and stronger EMI shielding materials. Thermoplastic compounds were born out of this quest. Thanks to their flexibility and cost effectiveness, they are fast replacing their metal counterparts, and are being used extensively to build more powerful shielding products.


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