Preparation and evaluation of nanocomposites based on acrylonitrile–butadiene rubber/rice husk waste

Abstract

Rice husk waste (RH) is a hard shell protecting the grain of rice and is found in plenty in countries producing rice. Rice husk is grinded to obtain fine powder and characterized by different techniques including Fourier transform infrared (FTIR), Elemental Analysis using Wavelength-Dispersive X-Ray Fluorescence (WD-XRF) Spectrometry, transmission electron microscope (TEM), and field emission scanning electron microscope (FESEM). Preparation of the nanocomposites occurs by using a laboratory two-roll mill. The nanocomposites are prepared by substitution of various ratios of nitrile butadiene rubber (NBR) by nanopowder rice husk (nRH). (NBR/nRH) mixes are prepared by concentrations of (100/0, 90/10, 80/20, 70/30, 60/40, and 50/50), respectively. The prepared nanocomposites are characterized by FTIR, FESEM, rheometric characteristics, physico-mechanical, and swelling properties. The results show an increase in the value of tensile strength of NBR by addition of 20 and 30 phr of nRH. The incorporation of nRH into NBR causes a decrease in the elongation at break with increasing nRH concentrations from 500 to 300%. The existence of nRH in the nanocomposites causes an increase in the value of hardness from 40 to 49.5 Shore A. The effect of addition of silica and HRH adhesion system on the nanocomposites (NBR/nRH20 and NBR/nRH30) is studied. The physico-mechanical properties of the nanocomposites are improved by addition of silica and HRH system. Surface morphology is studied by investigating FESEM images which confirm good dispersion of the prepared nanocomposites.