A new type of conductive rigid polyurethane foam can be used for antistatic packaging and electromagnetic shielding materials. The electrically conductive polyurethane foam has a stable electrical conductivity, and the volume resistivity does not change with time and temperature after testing. According to the research and development personnel, in the course of their research, they chose conductive fillers with stable conductive properties. Using a special dispersion process, a stable conductive path is formed inside the polyurethane matrix. After preliminary tests, the volume resistivity of polyurethane did not change from 0°C to 180°C, and the conductivity of the conductive polyurethane sample was also very stable at a high temperature of 150°C.
The accumulation and release of electrostatic charges seriously affect the safety of high-energy explosives, electronic equipment, integrated circuits, communications equipment, command systems, medical equipment, and other products during production, storage, transportation, handling, and use, often resulting in explosions, fires, and instrument failures. And so on, causing huge losses. According to a recent US survey, the average annual direct economic loss in investigations involving static electricity caused by damage in more than 10 industries amounted to more than US$20 billion. The loss of electronic components due to electrostatic hazard is only 100% per year in the electronics industry. Billions of dollars.
The various electronic components necessary for modern life are being developed in the direction of miniaturization, light weight, digitization, and high-density integration. The sensitivity is getting higher and higher, and it is susceptible to external electromagnetic interference and malfunctions, image obstacles, and sound barriers. Therefore, these products are required to be protected against static electricity and electromagnetic shielding during packaging and transportation. The premise of achieving electrostatic discharge and electromagnetic shielding is that there are conductive materials with good performance, and metals and their composite materials are generally used. Metals and their composites have good electrostatic discharge and shielding effectiveness, but they have the disadvantages of being bulky, difficult to adjust, requiring secondary processing, low production efficiency, and high cost. The conductive polymer material has the advantages of good electrostatic discharge and electromagnetic shielding performance, light weight, easy molding, easy conductivity adjustment, high production efficiency, and low total cost. From the structural point of view, foam plastic is undoubtedly the best antistatic packaging material and electromagnetic shielding material, because foam plastic has the advantages of light weight, excellent damping, easy molding, and low cost. According to the researcher, the density of the polyurethane foam developed by them is between 0.08g/cm3 and 0.60g/cm3, and the volume resistivity is between 106Ω·cm and 102Ω·cm. The volume resistivity can be adjusted and can also be based on the density. The different preparation of different volume resistivity samples.
It is reported that the College of Polymer Science of Sichuan University is currently seeking cooperation to prepare this conductive polyurethane foam into large-scale production.
Source: China Packaging News