A new method of producing conductive aramid fibers using supercritical carbon dioxide

In contrast to the pretreatment technology used in the conventional electroless metal plating of polymer materials, our newly developed supercritical pretreatment technology significantly reduces the large amount of wastewater necessary for the old process. In this new pretreatment process, palladium (II)-hexafluoroacetylacetonate (Pd(hfa)2) is impregnated into Kevlar® fiber/fabric, and it can be easily activated by over-heating without hydrogen. The treated Kevlar® fiber/fabric immersed in the electroless copper plating solution is coated with a shining copper film in a short time. By increasing the supercritical pretreatment time (range: 0–60 min) and the amount of Pd(hfa)2, it is possible to induce more copper to adhere to the impregnated Kevlar® in the same plating period. In addition, the effects of magnet stirring and ultrasonic irradiation during the electroless plating process were compared. It is clear that a better plating film with more complete coverage can be obtained by adopting the ultrasonic irradiation method.