Development of Radiation Crosslinking Nylon Molding Compound

摘要

Nylon66, which has high tenacity and high impact absorption, is a material widely used in the electrical and electronic fields as the material for connector, coil bobbin, fastener and so on. However, the growing concern about environmental problems is causing the electronic packaging industry to shift from lead-containing solder to lead-free solder, which has higher melting point. In lead-free soldering, heat resistance (reflow resistance) of 260 degrees C for 60 seconds is demanded, which means that Nylon66 with low melting point cannot be used. The authors have developed a new nylon molding compound by mixing Nylon66 with the crosslinking reagent and then molding it. After electron beam is irradiated, the authors obtained a crosslinked and unmelting molding made from Nylon66. This molding compound is applicable to lead-free solder, ensures UL94V-0 flame resistance, allows easy molding, and has a UL Temperature Index of 104 degrees C. The new molding compound was tested by a company which manufactures nylon connectors. It formed no bubbles on the surface after the reflow, and satisfied the evaluation criteria such as heat resistance, flame resistance, and cost. It was adopted as a molding compound for the heat resistant nylon connectors.