Shielding electronic components with conductive plastics

How well an electromagnetic interference (EMI) shield protects electronic products from radiation largely depends on the materials used. As engineers continue to take advantage of the material and processing benefits of plastics, they also make it more challenging to shield electronics from EMI. While plastics may be easier to shape and help cut the weight of components, engineering resins alone cannot conduct electromagnetic waves away from electronic circuits. To form a conductive path for EM waves, engineers rely on conductive paint and plating, metallic inserts, and conductively compounded resins. Conductive resins offer the greatest design freedom because they do not require secondary processing and are not limited by the capabilities of subsequent processing equipment such as spray-paint nozzles.