Now let's introduce the introduction of electronic shielding pouring materials. We are a chemical raw material manufacturer producing HTPB hydroxyl butadiene rubber such as hydroxyl terminated polybutadiene. We have 51 years of production process experience. Hydroxyl terminated polybutadiene hydroxyl butadiene rubber can be used as electronic shielding pouring materials. Do you know what electronic shielding pouring materials are? Let's have a look!

　　With the rapid development of modern electronic industry and the wide application of various electronic products, mobile communication, broadcasting, radar, magnetic therapy and computer have become frequent touch in people's daily life, making electromagnetic wave radiation a new social hazard. Electromagnetic radiation will affect people's health, seriously disturb the surrounding electronic instruments and equipment, make their working procedures abnormal and produce wrong actions; Together, electromagnetic radiation will leak information, so that computers and other instruments have no information security. Therefore, the electronic shielding castable should follow the trend. Now, the research on electromagnetic shielding materials mainly focuses on: new composite anti electromagnetic interference materials, nano anti electromagnetic interference materials, hexagonal anti electromagnetic interference materials, low-temperature sintered nizncu ferrite materials for multilayer chip filters, production of chip inductors and multilayer chip filters.

　　The working principle of electromagnetic shielding is as follows

　　Electromagnetic shielding uses shielding materials to block or weaken the transmission of electromagnetic energy between the shielding area and the outside world. The principle of electromagnetic shielding is to use the shielding body to reflect, absorb and guide the electromagnetic energy flow, which is closely related to the charge, current and polarization induced on the surface of the shielding structure and in the shielding body. According to its principle, shielding is divided into electromagnetic field shielding (electromagnetic wave shielding), electric field shielding (electrostatic shielding and alternating electric field shielding) and magnetic field shielding (low-frequency magnetic field shielding and high-frequency magnetic field shielding). Generally speaking, electromagnetic shielding refers to the latter, that is to shield the electric field and magnetic field together.

　　Now let's introduce the common shielding materials in the market

　　1、 Conductive elastomer fabric (conductive rubber)

　　All kinds of conductive adhesives are composed of silica gel, silicon fluoride, EPDM or fluorocarbon fluorinated silica gel and conductive fillers such as silver plated copper, silver plated aluminum, silver plated nickel, silver plated glass, silver plated lead or carbon particles

　　2、 Conductive composite agent

　　Conductive coatings include conductive coatings and adhesives. Conductive adhesive (I have to say hydroxyl terminated polybutadiene adhesive) is generally metal filler such as silver particles or silver copper particles, which is doped in epoxy resin or silica gel through special process, and flexible polyisoethylene. It has the common comprehensive functions of high shear strength, low coefficient of thermal expansion, ion purity, excellent thermal conductivity and conductivity. Typically, connectors containing EMI shielded channels, windows, or transparent conductive filaments on the shield are used.

　　3、 Absorbing material

　　Absorbing materials generally mix alloy powder and polymer resin through various processes and calender them into flexible sheets. Through hysteresis loss, dielectric loss, resistance loss and other mechanisms, it is transformed into heat energy, potential energy and other forms of energy to shield and absorb electromagnetic waves.

　　4、 Metal EMI fabric, clip fabric and claw beryllium copper reed

　　These varieties include woven wire mesh, surrounding wire mesh on elastomer core, directional wire and wire mesh in elastomer, which generally provide 60db-100db attenuation in the range of 20mhz-1ghz. It can be fixed to the slot of the box by conductive adhesive or mechanical means.

　　5、 EMI conductive foam fabric material

　　Conductive foam is a conductive sheath around the foam core made of polyurethane or EPDM. The conductive sheath is generally made of silver nickel plated nylon, aluminum or Monel wire (nickel copper alloy) or ferrex (tinned copper wire), which has excellent conductivity. It conforms to the flame retardant grade (ul94-v0) and has excellent mechanical functions such as elasticity and flexibility. Conductive foam liner has excellent shielding function. When it encounters electric waves, it will reflect and absorb according to the nature of its object, and provide shielding. It has high cost performance and is a widely used shielding material.

　　Source: semiconductor chemical manufacturer  www.sun-chem.cn