EMBEDDED PARTICULATE BIOMATERIALS AS DIELECTRIC FILLERS IN ELECTROACTIVE NATURAL RUBBER COMPOSITES

Abstract

ABSTRACT Both eggshell and eggshell membrane are potential alternative dielectric biomaterials because of their inorganic and organic matter contents, respectively. Adding eggshell or eggshell membrane into natural rubber compounds made using the sulfur curing system has many advantages such as flexibility, ease of formation, ability to operate under large strains and shape conformability, lightweight, and low cost of production. The results indicated that the natural rubber composite had a rubberlike characteristic and good elasticity. Both the eggshell and eggshell membrane acted as a dispersed-phase or dielectric filler that can absorb and store additional stress effects, resulting in fast curing and increasing crosslink density. Under a variable electrical field, eggshell and eggshell membrane particles induced dipolar moments and led to interparticle interactions that increased the storage modulus response substantially by nearly two orders of magnitude at 1.5 kV/mm. The obtained natural rubber composites can contribute toward more effective polarization and hence stronger electrostatic interactions between the embedded particles, resulting in a fast deflection response due to the dielectrophoresis force generation at low electrical field strengths of 300 and 350 V/mm for eggshell and eggshell membrane, respectively. The additional advantage of eggshell waste utilization is welcome as a means of reducing global climate warming and adding value to eggshell waste.