volume | PIER Journals

Abstract

Organic-inorganic thermoplastic composites offer a cost-effective material choice with tuneable dielectric properties for various telecom components and applications. Typically such composites require substantial loading of inorganics to obtain a feasible level of permittivity at RF frequencies dramatically decreasing mechanical ruggedness and increasing losses. In this paper we demonstrate utilization of nanoparticle phase in BaSrTiO₃-polypropylene-graft-poly (styrene-stat-divenylbenzene) composite to enhance the high frequency properties and overcome the problems associated with high filler loading. The effect of nanosize silicon, silver and Al₂O₃ additives with different volume fractions in complex permittivity was investigated up to 1 GHz. Significant increase in the effective permittivity of the composites with all the additives was observe, especially in the case of the nanosized silver particles where only 2 vol.% addition was able to enhance ε_r by 52% without increasing the dielectric losses when compared to the reference sample.

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Dr. Merja Teirikangas

Dr. Jari Juuti

Professor Heli Jantunen