To read this content please select one of the options below:

Electrical studies on biopolyurethane from cashew nut husk tannin

A.J. Sunija (Department of Chemistry, University College of Engineering Nagercoil, Anna University, Nagercoil, India)
S. Siva Ilango (Department of Chemistry, Thiagarajar College of Engineering, Madurai, India)
K.P Vinod Kumar (Department of Chemistry, University College of Engineering Nagercoil, Anna University, Nagercoil, India.)

Circuit World

ISSN: 0305-6120

Article publication date: 2 February 2015




This paper aims to focus on the evaluation of the electrical properties of bio-based polyurethane material derived from cashew nut husk tannin and also the effect of temperature and frequency on the dielectric values and alternate current (AC) conductivity.


Bio-based polyurethane is prepared from cashew nut husk tannin as polyol, their dielectric constant and dielectric loss factor are measured using an inductance capacitance resistance (LCR) metre, and the AC conductivity is determined using dielectric constant and loss values.


The dielectric constant values are high, and the values decrease with an increase in frequency but increase with an increase in temperature. The AC conductivity values are low; hence, the material can be categorized as insulators or semi-conductors. Because the polyurethanes have a good dielectric value and are cost-effective, as they are derived from renewable biomaterial waste, they have promising applications for the future.

Research limitations/implications

The experiment is carried out up to the frequency of 200 KHz because of the limitation in the instrument. But for the institute of printed circuits (IPC) and other specifications, the values of dielectric loss and dielectric constant will be generally coated for 1 MHz.

Practical implications

The high dielectric constant and loss values show that the polyurethane can be opted for use as capacitors in electronic devices, and the values are comparable to the requirements of IPC4101A/24IPC; hence, they are suitable for the application as printed circuit board (PCB) laminate.

Social implications

The use of biomaterial waste in the production of polyurethane will bring down the dependence of polyurethane industry on fossil fuel reserve, reduce carbon dioxide foot print and reduce the cost of production.


The motivation of the work was its ecological aspect and also aims on the use of an alternative bio-based material in the PCB industry.



The authors are thankful to the authorities of St. Joseph College, Tirchy, for providing the laboratory facilities to measure the dielectric constant and loss factor values.


Sunija, A.J., Siva Ilango, S. and Vinod Kumar, K.P. (2015), "Electrical studies on biopolyurethane from cashew nut husk tannin", Circuit World, Vol. 41 No. 1, pp. 41-46.



Emerald Group Publishing Limited

Copyright © 2015, Emerald Group Publishing Limited

Related articles