Polymer matrix composites have generated a great deal of attention in recent decades in various fields due to numerous advantages polymer offer. The advancement of technology has led to stringent requirements in shielding materials as more and more electronic devices are known to cause electromagnetic interference (EMI) in other devices. The drive to fabricate alternative materials is generated by the shortcomings of the existing metallic panels. While polymers are more economical, easy to fabricate, and corrosion resistant, they are known to be inherent electrical insulators. Since high electrical conductivity is a sought after property of EMI shielding materials, polymers with fillers to increase their electrical conductivity are commonly investigated for EMI shielding. Recently, composites with nanofillers also have attracted attention due to the superior properties they provide compared to their micro counterparts. In this review polymer composites with various types of fillers have been analysed to assess the EMI shielding properties generated by each. Apart from the properties, the manufacturing processes and morphological properties of composites have been analysed in this review to find the best polymer matrix composites for EMI shielding.

Many of the construction materials available are known to cause a drastic level of damage to the environment during their manufacturing stages. Hence, many researchers have attempted to formulate construction materials that are more environmentally friendly. Additionally, the rise in wireless communications in recent decades has seen a rapid increase in electromagnetic pollution and interference, which affects the functionality of sensitive electronic devices. This research is focused on fabricating a more sustainable construction material that could prevent electromagnetic interference for electronic devices housed inside. Carbon fibres of three different lengths were added in four variations to a geopolymer control mix to study their effect on electromagnetic interference shielding. The results showed that the amount of shielding produced by these composites increases with carbon fibre length and quantity. Morphological analyses showed that the interconnectivity of the fibres plays a crucial role in having a high level of shielding. While the flexural strength showed an improvement with the addition of carbon fibre, the compressive strength showed a slight reduction with the increase in carbon fibre length. The optimal level of shielding was produced by the specimen containing 0.7% of 12 mm carbon fibre, which was the maximum amount of fibre of any length used in this study; the optimal level of shielding generated was 43.43 dB within the frequency range of 30 MHz to 1.5 GHz.