Influences of trans‐polyoctylene rubber on the physical properties and phase morphology of natural rubber/acrylonitrile–butadiene rubber blends

Abstract

ABSTRACT:The influence of trans-polyoctylene rubber (TOR) on the mechanical properties, glass-transition behavior, and phase morphology of natural rubber (NR)/acrylonitrile-butadiene rubber (NBR) blends was investigated. With an increased TOR level, hardness, tensile modulus, and resilience increased, whereas tensile strength and elongation at break tremendously decreased. According to differential scanning calorimetry and dynamic mechanical analysis, there were two distinct glass-transition temperatures for a 50/50 NR/NBR blend, indicating the strongly incompatible nature of the blend. When the TOR level was increased, the glass transition of NBR was strongly suppressed. NBR droplets of a few micrometers were uniformly dispersed in the continuous NR phases in the NR/NBR blends. When TOR was added to a 50/50 NR/NBR blend, TOR tended to be located in the NR phase and in some cases was positioned at the interfaces between the NBR and NR phases.

Effect of the processing conditions and the addition of trans‐polyoctenylene rubber on the properties of natural rubber/styrene–butadiene rubber blends

“…This effect was larger Compound NR1 NR2 SBR1 SBR2 C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 As shown in Figure 4, upon the addition of TOR to the blend, Storage extensional modulus (E 0 ) decreased in the glassy region (<2608C) and increased in the rubbery region (>2408C), which corroborated the results of Nah et al 6 As shown in Figure 5, tan d showed a maximum at 259.08C for NR, 246.08C for SBR, and 2618C for the TOR pure phases. In a multicomponent system, dynamic mechanical analysis evaluates the changes in the individual glass-transition temperatures (T g 's) of the components.…”

“…However, the addition of TOR resulted in an improvement in hardness and a decrease in tearing resistance, which corroborated the results obtained by Nah and coworkers. 2,6 The increase in hardness with the addition of TOR was probably due to the fact that the relative degree of crosslinking was much higher than for the other rubber components. 6 However, no direct correlation between the degree of crosslinking of the compounds and the hardness could be found.…”

“…In the case of NBR/ NR, it was shown that TOR was located at the interface between NBR and NR. 6 To our knowledge, no morphological study of SBR/NR blends to which TOR was added has been conducted so far. Therefore, more studies to describe how the TOR modifies the morphology and the properties of NR/SBR blends are necessary.…”

Morphology and dynamic mechanical properties of natural rubber/nitrile rubber blends containing trans‐polyoctylene rubber as a compatibilizer

“…DMA can be used as a tool to characterize the effect of phase morphology on dynamic mechanical properties. The influence of the morphology of NR/NBR/TOR blends on dynamic mechanical properties was reported in our previous publication 17. However, the present investigation was aimed at giving further details about dynamic mechanical properties of NR/NBR immiscible blend with respect to the phase morphology obtained from AFM.…”

“…The influence of TOR in modifying the phase morphology of NR/EPDM and NBR/EPDM blends has been investigated by Chang et al 12, 15 In our earlier investigation,16 we reported the effect of TOR on the rheological and mechanical properties of NR/NBR blend. In another publication,17 the authors studied the influence of TOR on the cure behavior and physical and morphological properties of NR/NBR blend.…”