Polymer matrix composites : Conductivity enhancement through polypyrrole coating of nickel flake

• Published in: Journal of materials science Vol. 33; no. 12; pp. 3085 - 3093
• Main Authors: GENETTI, W. B, YUAN, W. L, GRADY, B. P, O'REAR, E. A, LAI, C. L, GLATZHOFER, D. T
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 15-06-1998; Springer Nature B.V
• Subjects: Applied sciences; Coating; Composites; Contact resistance; Electric contacts; Electrical resistivity; Exact sciences and technology; Fillers; Forms of application and semi-finished materials; Load resistance; Low density polyethylenes; Materials science; Mechanical properties; Nickel; Percolation; Polymer industry, paints, wood; Polymer matrix composites; Polypyrroles; Technology of polymers; Electrical conductivity; Electrical properties; Dispersion reinforced material; Experimental study; Property processing relationship; Composite material; Surface treatment; Conducting polymers; Heterogeneous polymerization; Low density ethylene polymer; Concentration effect; Nickel; Pyrrole polymer
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1023/A:1004387621165

The electrical resistance of polymeric materials loaded with conductive fillers can be divided into three major categories: the intrinsic resistance of the filler and matrix, the particle–particle contact resistance, and the tunnelling resistance. A method for decreasing both the particle–particle contact and the tunnelling resistance in nickel-filled low-density polyethylene composites which involves coating the nickel with polypyrrole (PPy) using admicellar polymerization has been developed. It is believed that these resistances are reduced by the formation of PPy "molecular wires" which occur as a result of chain entanglements at high filler loadings. Coating the nickel particles with PPy leads to a three-order-of-magnitude increase in conductivity at concentrations well above the percolation threshold without significantly changing the thermal or mechanical properties of the composite. © 1998 Kluwer Academic Publishers