无钯化学镀制备导电Ni@Kevlar®复合织物及其电磁屏蔽性能

Electroconductive Ni@Kevlar® composite fabric prepared by palladium-free electroless plating and electromagnetic shielding properties

采用高性能Kevlar®织物作为基体,使用无刻蚀、无钯、无锡的“溶胀-银”方法进行活化,通过化学镀工艺制备Ni@Kevlar®织物。利用扫描电子显微镜(SEM)和高分辨率透射电子显微镜(HRTEM)观察织物表面及纤维截面的微观形貌,探究不同时间下样品的质量增加率、增厚及面密度,并利用X射线光电子能谱仪(XPS)和广角X射线衍射仪(WXRD)测量表面成分及晶体结构,采用四探针测试仪和综合物理性能测量系统(PPMS)测量电、磁性能。结果表明,无刻蚀、无钯、无锡的“溶胀-银”活化处理能在织物表面产生大量的银催化靶点,经化学镀后可得到具有良好导电性和铁磁性的纯镍镀层。同轴法屏蔽效能测试结果表明,Ni@Kevlar®织物在低频波段(0.1 MHz~1.5 GHz)的屏蔽值最高达70 dB,能屏蔽99.99999%的电磁波,高频波段(2~18 GHz)达到25 dB,可满足生活生产的屏蔽需求。

Ni@Kevlar®fabric was prepared by electroless plating process using high performance Kevlar®fabric as substrate and activated by etchant-free,palladium-free,and tin-free swelling-silver pretreatment.SEM and HRTEM were used to observe the morphology of the fabric and the cross section of the fiber.The mass gain,thickness and areal density of the samples at different plating time were investigated.The composition and structure of different Ni@Kevlar®fabrics were measured by EDS,XPS and WXRD.The electrical and magnetic properties of the materials were measured by four-probe tester and PPMS. Results showed that the exploitation of etchant-free, Pd-free, tin-free swelling-silver activation was very simple and efficient to fix massive silver seeds into the fiber matrix and facilitate the ensuing electroless Ni plating process with maintenance of the remarkable properties of the Kevlar® fabric, and exerted positive influence over the adhesion between the fiber matrix and the subsequent pure Ni nano-crystalline layer. Coaxial electromagnetic shielding test results demonstrated the excellent shielding effectiveness (up to 70 dB) at low-frequency band (0.1 MHz~1.5 GHz) and the fair shielding effectiveness (up to 25 dB) at high-frequency band (2~18 GHz), which could well meet the electromagnetic shielding needs of life and production.