Influence of porosity on resistivity of polypropylene foams

Abstract

Polymer foams are often used as bone material substitutes for insulation applications, due to better reproducibility and availability. This work deals with the electrical and dielectric properties of foamed polypropylene. Main objective of this research is to develop a theoretical model for resistivity of polypropylene foam, based on porosity. Physical properties of polypropylene foam were experimentally investigated. Porosity was systematically varied and the electrical resistivity and dielectric constant were determined for its various levels of foams. For foamed polypropylene, the relationship between resistivity and porosity is proposed. Resistivity increases with porosity. An equation is presented to describe the relationship between porosity and resistivity of polypropylene foams. Resistivity values of polypropylene foams calculated by using the proposed equation fits well with the experimental values. Dielectric constant of foamed polypropylene samples varying in foaming concentration present in polypropylene is determined.

Keywords

PP foam resistivity dielectric constant porosity

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