Dynamic mechanical behavior of acrylonitrile butadiene rubber/poly(ethylene‐co‐vinyl acetate) blends

Abstract

The dynamic mechanical behavior of uncrosslinked (thermoplastic) and crosslinked (thermosetting) acrylonitrile butadiene rubber/poly(ethylene-co-vinyl acetate) (NBR/EVA) blends was studied with reference to the effect of blend ratio, crosslinking systems, frequency, and temperature. Different crosslinked systems were prepared using peroxide (DCP), sulfur, and mixed crosslink systems. The glass-transition behavior of the blends was affected by the blend ratio, the nature of crosslinking, and frequency. sThe damping properties of the blends increased with NBR content. The variations in tan ␦ max were in accordance with morphology changes in the blends. From tan ␦ values of peroxide-cured NBR, EVA, and blends the crosslinking effect of DCP was more predominant in NBR. The morphology of the uncrosslinked blends was examined using scanning electron and optical microscopes. Cocontinuous morphology was observed between 40 and 60 wt % of NBR. The particle size distribution curve of the blends was also drawn. The Arrhenius relationship was used to calculate the activation energy for the glass transition of the blends, and it decreased with an increase in the NBR content. Various theoretical models were used to predict the modulus of the blends. From wide-angle X-ray scattering studies, the degree of crystallinity of the blends decreased with an increasing NBR content. The thermal behavior of the uncrosslinked and crosslinked systems of NBR/EVA blends was analyzed using a differential scanning calorimeter.

Improving the properties of reclaimed waste tire rubber by blending with poly(ethylene‐co‐vinyl acetate) and electron beam irradiation

“…This might also suggest the distribution of size or amount of EVA crystallite is similar in these blends. A few studies have also noted similar observation in rubber/plastic blends (Varghese et al, 2002, Saleesung et al, 2010. Study conducted by Ratnam et al (2014) concluded the presence of ground tire rubber in EVA matrix has a disrupting role in the EVA chain molecules arrangement when cooling from melt, thus reducing the crystallinity of the blend.…”

Thermal degradation and crystallisation studies of reactively compatibilised polymer blends

“…are used in many demanding applications where the properties of thermal stability and fire resistance are priorities and therefore have been extensively studied [1][2][3][4]. Polymer blending has been reported to have great impact on the thermal stability of polymers [5][6][7][8][9][10][11][12][13]. Compatibility between two components in a binary blend is one of the decisive factors, which determines the thermal stability of polymer blends [14][15][16][17][18][19], and therefore compatibilisation has profound effect on the thermal stability of polymer blends.…”

Dynamic mechanical properties and morphology of polyethylene/ethylene vinyl acetate copolymer blends

“…The damping properties of the blends increased with NBR content. 19 Recently in another work, Thomas et al have reported the effect of blending ratio, reactive compatibilization, and dynamic vulcanization of high-density polyethylene (HDPE)/EVA blends. 20 Sethi et al have investigated the dynamic mechanical properties of nonirradiated and irradiated blends of low-density polyethylene and ethylene vinyl acetate copolymer blends.…”