Natural Rubber/Carbon Nanotube/Ionic Liquid Composite Membranes: Vapor Permeation and Gas Permeability Properties

Abstract

Natural rubber (NR)/carbon nanotube/ionic liquid nanocomposite membranes, prepared by using sulfur as the crosslinking agent, are tested for their vapor permeation (VP) characteristics. The permeation studies are conducted using three solvents, pentane, hexane and heptane as aliphatic solvents and toluene as aromatic solvent. The effects of the ionic liquid loading, CNT loading, and penetrant size on the vapor permeability of the membranes are investigated. The vapor permeability of the nanocomposite is found to increase with an increase in the ionic liquid content and decreases with CNT loading. Generally, cyclohexane is produced by the catalytical hydrogenation of benzene at high temperature. It is very difficult to purify it by removing unreacted benzene due to the close boiling point of cyclohexane and benzene and their azeotropic mixture formation tendency. By using NR/CNT/IL nanocomposite membrane, VP technique is applied for the separation of benzene/cyclohexane mixtures, including azeotropic composition of the solvents. The gas permeabilities of the NR, NR/CNT3, and NR/CNT3/IL membranes are determined with nitrogen and oxygen. Among these membranes, NR/CNT3/IL shows highest permeability. Compared to nitrogen, oxygen shows higher permeability.

Multifunctional Applications of Ionic Liquids in Polymer Materials: A Brief Review

“…The reason was the increased free volume of NR/CNTs/ILs membrane, due to the plasticizing properties of ILs. Furthermore, vapor permeation of NR/CNTs/ILs membrane was also successfully applied to the low-cost separation of benzene/cyclohexane azeotropic mixtures [20]. When suitable nano-fillers were added, the polymeric membrane material improved the overall selectivity [22].…”

“…Due to the high efficiency, excellent performance, and low risk, ILs could replace specific components in many applications; for example, small amounts of ILs could catalyze silanization reactions efficiently and enhance the interfacial interaction of composites. Meanwhile, they are relatively easy to be recycled by extraction and distillation, which reduces their cost in industrial applications and expands their fields of application, such as sensors [12][13][14], batteries [15][16][17][18], ionized gels [19], separation membrane [20][21][22][23][24], etc. Currently, the applications of ILs are becoming more and more extensive in polymer materials, which involve rubber [25][26][27], plastics [28], polyurethane [29,30], epoxy resins [31][32][33], thermoplastic elastomers [34,35], and bio-based polymers [36].…”

Carbon Nanotubes Networking in Styrene‐Butadiene Rubber: A Dynamic Mechanical and Dielectric Spectroscopy Study

“…Carbon nanotubes (CNT) are one of the more suitable candidates to replace, totally or partially, carbon black (CB), thus allowing the reduction of the filler content without diminishing the mechanical performance. [ 1–8 ]…”

“…Carbon nanotubes (CNT) are one of the more suitable candidates to replace, totally or partially, carbon black (CB), thus allowing the reduction of the filler content without diminishing the mechanical performance. [1][2][3][4][5][6][7][8] The improvements achieved in the final properties of the reinforced materials are strongly influenced by the particle-polymer interaction degree, which in turn depends on several factors, such as size and geometry of the particle, degree of dispersion and energetic distribution of the surface. [9,10] In the case of elastomers reinforced with CB, there is an intensive polymer-filler interaction, and polymer chains anchor to the filler surface.…”