Innovative thermoplastic material for electromagnetic spectrum management brings multiple benefits (1)

Fully understanding the spectrum of electromagnetic (EM) and its interaction with thermoplastic materials, help in the application of existing and new space using modified thermoplastic material.

Designers in the development of electrical/electronic device EM spectrum must be taken into account, so that these devices or electromagnetic wave transparent, or shielding, reconnaissance, attenuation, electromagnetic wave absorption and reflection. Although management EM radiation method varied, but with the inner shield features innovative thermoplastic materials can bring diverse design, performance and environmental benefits and economics.

Management EM spectrum

As the name implies, EM spectrum refers in accordance with the frequency and wavelength to arrange all of the continuous spectrum of electromagnetic waves (as shown in Figure 1).

Typically, the wavelength of the radiation is divided into multiple EM radiation types, including radio waves, microwaves, x-rays and gamma rays. Many materials such as composite engineering thermoplastics, in equipment design plays a unique role, they can make the equipment and appropriate interaction of electromagnetic radiation. In the manufacture of thermoplastic plastics and fiber reinforced composite material (FRP), resins, fillers and reinforcing agent selection will significantly affect materials on EM radiation generated by the reaction.

Figure 1: electromagnetic spectrum

Resolve EMI/RFI shielding devices on

TV set, mobile phone, wireless Internet, in-car infotainment systems, medical equipment and many other devices you may need to transfer data using radio waves.

However, if no electromagnetic interference, equipment performance will be greatly diminished. For example, is currently in the process of designing a new portable medical equipment for the doctor at the clinic, battlefield or accident scene and other remote sites more quickly for diagnostic evaluation. These devices can be high accuracy, high efficiency, the accuracy of the diagnosis results is critical. To do this, you must control the electromagnetic interference (EMI)/radio frequency interference (RFI). Use the shell to protect the device itself or peripheral equipment against electromagnetic interference shielding function can be achieved. However, the weight of the metal shell will affect medical device portability. With shielding of thermoplastic materials not only reduces weight and improves design flexibility, color and parts integration.

Usually by the following three methods to have inherent insulation of classic thermoplastic shell can be suitable for shielding: catalyzing use metal lining, coloured metal coating or use vacuum metal plating technology.

Although these methods could provide a good electromagnetic shielding, but because you need to configure the device, such as racks, fixtures, shield device, tool and process equipment, etc., cost also increases. In addition, these actions can affect the delivery of products, some of which are also causing damage to the environment. Use of copper and other metals on parts coating treatment is difficult to ensure that all regional coating thickness uniformity and durability, the characteristics of the complex and deep stamping parts. In addition, the coating of parts, assemble or use some of the metal coating defects such as scratches or damage will affect its shield performance.