Biodegradable Coir Based Hierarchical Porous Cellulose Dielectric Materials with Low Df for Insulating Material Application

Abstract

In this work, the dielectric properties of modified lignocellulosic biodegradable coir fibers were studied. Modifications comprise of transesterification with butyl acrylate (BA) and subsequent curing with benzoyl peroxide (BPO), that remove the cementing materials resulting in a decrease in the dielectric constant (K) and the dissipation factor (Df). The decrease in K of the modified coirs (MCs) is due to its enhanced hydrophobicity. Removal of cementing materials favor the formation of uniform holes/pores in the MCs resulting in large number of interfaces, subsequently these interfaces restrain the motion of charges, which decreases the Df values. It is established that removal of the cementing materials i.e. lignin from the parent coir (PC) lead to better dielectric materials. The hydrophobicity, resistance power to chemical damage, crystallinity, tensile strength and thermal stability increases respectively for MCs in comparison to PC except the Zeta potential which decreases. More importantly, the sintering temperature can go as high as 500 degrees C or more for MCs, which are suitable for integrated circuit design lithography process. These biodegradable coir fibers due to their higher packing density, thermal stability and insulating properties could be very important materials for embedded capacitors, different electronic devices and microelectronics applications.