Optimized process for the inclusion of carbon nanotubes in elastomers with improved thermal and mechanical properties

Abstract

The effects of addition of reinforcing carbon nanotubes (CNTs) into hydrogenated nitrile-butadiene rubber (HNBR) matrix on the mechanical, dynamic viscoelastic, and permeability properties were studied in this investigation. Different techniques of incorporating nanotubes in HNBR were investigated in this research. The techniques considered were more suitable for industrial preparation of rubber composites. The nanotubes were modified with different surfactants and dispersion agents to improve the compatibility and adhesion of nanotubes on the HNBR matrix. The effects of the surface modification of the nanotubes on various properties were examined in detail. The amount of CNTs was varied from 2.5 to 10 phr in different formulations prepared to identify the optimum CNT levels. A detailed analysis was made to investigate the morphological structure and mechanical behavior at room temperature. The viscoelastic behavior of the nanotube filler elastomer was studied by dynamic mechanical thermal analysis (DMTA). Morphological analysis indicated a very good dispersion of the CNTs for a low nanotube loading of 3.5 phr. A significant improvement in the mechanical properties was observed with the addition of nanotubes. DMTA studies revealed an increase in the storage modulus and a reduction in the glass-transition temperature after the incorporation of the nanotubes. Further, the HNBR/CNT nanocomposites were subjected to permeability studies. The studies showed a significant reduction in the permeability of nitrogen gas.

Transport performance in novel elastomer nanocomposites: Mechanism, design and control

“…For example, hydrogenated nitrile rubber (HNBR)/CNTs nanocomposites exhibited a significant reduction in the permeability of nitrogen gas [277]. The resistance to chloroform of HNBR was improved by incorporating fibrillar sepiolite [278].…”

Mechanism of Gas Permeation in Processed HNBR/Nanoclay Composites

“…This improved reinforcement might be attributed to predispersion of organoclays into the HNBR matrix by sonication. Even at higher loadings of 15 phr, XRD patterns 17 (not shown here) show a lesser intercalated/exfoliated structure in the samples when compared to HNBR/FD samples. This can also be attributed to a large reduction in aggregations of silicate layers because of ultrasonication.…”

“…The detailed XRD analysis can be found elsewhere. 17 A peak is present at 2θ = 8.6 • , d = 10.3 nm for H15AFD15 nanocomposite samples. We can see that there is a shift in peak and it suggests the presence of a more intercalated structure.…”

“…The sectioning details have been reported in detail in our previous articles. 17 The ultrathin sections of 50 nm were carefully placed on a 200mesh formvar-coated copper grid for performing TEM analysis. High-resolution TEM analysis was performed on a FEI Technai G2 FEG transmission electron microscope operated at an accelerating voltage of 120 kV.…”

Multifunctionalized Carbon Nanotubes Polymer Composites: Properties and Applications

“…Generally, the applications of elastomeric need the significant deformation extensibility and resilience of the elastomer. After incorporation of CNTs, as highly rigid fillers in elastomers, it typically needs to improve the stiffness of overall large-strain deformation behavior of composites (Cadambi and Ghassemieh 2012). Besides, this approach is likewise maintaining the key features of large strain-to-break behavior as well as large strain resilient of composites.…”