The effects of hybrid fillers on the electrical conductivity and electromagnetic interference (EMI) shielding effectiveness (SE) of polyamide 6 (PA6)/polypropylene (PP) immiscible polymer blends were investigated. Carbon black (CB) and steam exploded sisal fiber (SF) were used as fillers. CB was coated on the surface of SF, and this was exploded by water steam to form carbon black modified sisal fiber (CBMSF). CB/SF/PA6/PP composites were prepared by melt compounding, and its electromagnetic SE was tested in low-frequency and high-frequency ranges. We observed that SF greatly contributed to the effective decrease in the percolation threshold of CB in the PA6/PP matrix and adsorbed carbon particles to form a conductive network. Furthermore, an appropriate CB/SF ratio was important for achieving the best shielding performance. The results indicate that CBMSF was suitable for use as electronic conductive fillers and the CB/SF/PA6/PP composites could be used for the purpose of EMI shielding. V C 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42801.

Supercritical CO 2 assisted electroless plating on polypropylene substrate-effect of injection speed on adhesive force of metal to polymer AIP Conference Proceedings 1713, 040002 (2016) Abstract. Polymer composites filled with conductive carbon black (CB) are gaining popularity for electromagnetic shielding applications. Dynamic injection molding method was adopted to study the influences of vibration force field on electrical properties of polypropylene/CB composites. The results showed that the percolation phenomenon of conductivity of composites occurred at 15wt% and the calculated SE was positive correlated with the variation trend of conductivity. The calculated SE of composite was more than 30dB at a CB concentration of 30wt%, which could obtain good shielding effects. The result could offer optimum vibration parameters for producing electromagnetic shielding composites by respectively changing the amplitudes and frequencies of the vibration force field.

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This study underlines the ceramic BaTiO3 dielectric layer adjacent to the electrode of long-term reliability-improved Ni-Sn alloy internal electrode BaTiO3-based multilayer ceramic capacitor to clarify the cause of electric barrier formation. Electron energy loss spectroscopy measurements of the Ti L3,2 near the edges and the O K near the edge structure changes to characterize the existence of an oxygen vacancy region, approximately 60 nm in width, and generated in BaTiO3 adjacent to the interface. Accordingly, the n-type semiconductor layer of BaTiO3 that originated from the oxygen vacancies, led to the formation of a rigid Schottky barrier at the interface.