EMI can simply be a nuisance, such as radio static. It can also degrade, disrupt and destroy devices. As electronics become faster and smaller, they require greater circuit bandwidth and become more vulnerable to EMI. The transition from analog to digital circuits also raises the risks of EMI. Many factors contribute to EMI, including energies, frequencies, waveforms and cavity dimensions. It is not possible to predict exactly whether and if EMI will occur.
To control EMI, engineers use conductive materials that reflect, scatter and absorb unwanted energy. These materials technologies are also used for multi-spectral camouflage, commonly known as stealth.
When a wave of energy makes contact with an EMI shielding material, it will be reflected or absorbed. Depending upon the thickness of the material—its skin depth– the material will provide reflection loss and shielding effectiveness. EMI shielding and absorbing materials can block more than 99.99% of the incident energy, protecting electronics from harm. Metal materials and carbon loaded products are highly reflective.
Conductive polymers manufactured by Eeonyx are important because they provide a combination of reflection and absorption. Eeonyx materials have high dielectric loss: they dissipate electromagnetic energy as heat.
The energy absorbing property of conductive polymers is a useful complement to shielding materials. Shielding materials reflect unwanted external energy but they also retain potentially harmful energy emitted from inside a device. Energy absorbing conductive polymers deliver a more comprehensive solution for managing EMI. The energy absorbing property also helps to hide reflective objects, such as metal planes and ships from hostile radar.