EFFECT OF ORGANICALLY MODIFIED MONTMORILLONITE CLAY ON MORPHOLOGICAL, PHYSICOMECHANICAL, THERMAL STABILITY, AND WATER VAPOR TRANSMISSION RATE PROPERTIES OF BIIR-CO RUBBER NANOCOMPOSITE

Abstract

ABSTRACT Rubber nanocomposites based on bromobutyl rubber (BIIR), polyepichlorohydrin rubber (CO), carbon black (CB), and organically modified montmorillonite clay (NC) were prepared via melt compounding technique. Effects of NC dosage on various properties of the developed BIIR-CO nanocomposites were studied. Morphological characteristics of the BIIR-CO nanocomposite revealed a good level of clay dispersion. Scanning electron microscopy analyses of the tensile fractured surfaces of the nanocomposites revealed the existence of a good interaction between NC-CB. Hybrid microstructure development between NC and CB, clay exfoliation, and improved filler dispersion in the quaternary nanocomposite significantly contributed to the overall enhancement of properties. The addition of nanoclay increases the modulus up to 54%, tear strength up to 20%, and other physicomechanical properties of the rubber nanocomposite. However, higher nanoclay dose results in the agglomeration of clay particles predominantly. An increase in the volume fraction of nanoclay platelets depreciates the thermal degradation of the BIIR-CO nanocomposites. The tortuous path offered by NC is pivotal in the significant reduction in the water vapor transmission rate (up to 30% reduction). Contact angle measurements reveal the importance of nanoclay dispersion in subsiding the surface hydrophilic nature of the nanocomposite.