Insulating Plastic Material For Heavy-duty Connectors

The insulation materials used in heavy duty electric cable connectors can be divided into thermosetting plastics and thermoplastic plastics. Thermosetting plastics of type heavy duty automotive electrical connectors include phenolic resins, diallyl phthalate, epoxy resins, and unsaturated polyesters. Thermoplastic plastics mainly include glass fiber reinforced PET, PBT, PCT, PA6, PA66, PA6T, PA9T, polypropylene terephthalate, polyetherimide, polyethersulfone, polyarylsulfone, and polyaryl ether.

In addition to the previously mentioned heavy duty 12v connectors material, there is also the heavy duty 12 volt connectors material developed by Germany specifically for surface mount technology—modified PPS and a new type of LCP. Compared to ordinary PPS, modified PPS has significantly improved flowability by half, shortened the molding cycle by half, reduced molding pressure by 40%, and can be reinforced with up to 40% glass fiber. The new LCP has a lower processing temperature, 50°C lower than ordinary insulating plastic materials, reduces molding pressure by half, and significantly shortens the molding cycle. It can be made into thin, small, and complex 12v heavy duty connector. How should these materials be selected for different applications?

For low-frequency heavy duty crimp connectors, the materials used in the past were mostly mineral-filled phenolic plastics, but the production efficiency was low, so they have been replaced by new thermoplastics such as PA, PC, reinforced PC, and polysulfone. For use in humid and hot conditions, DAP material can be used. If the application requires high sealing performance, sulfur-free or low-sulfur rubber with good dielectric properties can be selected, such as silicone nitrile rubber, fluororubber, etc.; if it is high frequency heavy duty waterproof electrical connectors, GFPA material can be selected. This material has low cost, good processing fluidity, and can produce thin-walled products. If dimensional stability and heat resistance of the connector are required, GFPBT material can be selected. PPS and LCP can only be selected based on heat resistance requirements; if the connector pitch is only 1.27mm, PES or PEI can be selected to meet dimensional accuracy and processability requirements. High heat-resistant materials are used for surface decoration, such as glass fiber reinforced PA46, PA6T, PA9T, PPA, etc. These should be selected because the surface decoration needs to withstand 250℃ for 5 seconds.