Microwave Absorbing Coatings Based on a Blend of Nitrile Rubber, EPDM Rubber and Polyaniline

摘要

The mechanical and microwave radiation absorbing properties of conductive ternary blends based on nitrile rubber, EPDM rubber and polyaniline, doped with dodecylbenzene sulfonic acid, have been investigated with special interest in the concentrations of nitrile rubber and conductive polymer in the blend. The ternary blends were prepared by melt blending using an internal mixer. Mechanical properties and soluble fraction analyses show that crosslinking occurs during blending, and that the crosslinking degree depends on the concentrations of doped polyaniline and nitrile rubber in the blend. The crosslinking reaction involves the doping acid (dodecylbenzene sulfonic acid) of polyaniline and the -C≡N group in the nitrile rubber. The ternary blends can be used for microwave absorption in the frequency range of 8–12 GHz. This property depends on the concentration of the conductive polymer and film thickness.