Aramid pulp reinforced hydrogenated nitrile butadiene rubber composites with ionic liquid compatibilizers

Abstract

Although carbon black is an effective reinforcement for most rubbers, its replacement by other fillers would be beneficial. Aramid fibers are used in a range of applications in the rubber industry, providing dimensional stability prior to vulcanization and improving the mechanical properties of the elastomeric product. Nevertheless, their relatively inert surface is an obstacle in the exploitation of their full potential. In this work, two ionic liquids were investigated as compatibilizers in the preparation of hydrogenated nitrile butadiene rubber composites with aramid pulp and carbon black fillers. The materials were characterized using swelling, hardness and tensile tests, differential scanning calorimetry, thermal gravimetric analysis, and infrared spectroscopy. The carbon black‐free composite prepared from aramid pulp treated with 1.0 wt% of 1‐carboxymethyl‐3‐methylimidazolium chloride outperformed all other studied materials, presenting a higher modulus at 100% strain (7.31 MPa), while maintaining high strain at break. Thus, ionic liquids were found to potentialize the aramid reinforcement effect in these rubber composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48702.

Macro-, Micro- and Nanomechanical Characterization of Crosslinked Polymers with Very Broad Range of Mechanical Properties

“…The increase in the stiffness-related properties with T g (Equation (5)) for amorphous crosslinked polymers is a general rule and well-known trend, but it is worth re-emphasizing that it holds just within a given set of similar samples. In the systems of crosslinked polymers, in which the authors changed not only the crosslinking density, but also morphology, components and/or fillers of the crosslinked resin, the correlations between stiffness-related properties and glass transition temperature were very weak or disappeared completely [ 46 , 74 ]. In our series of homogeneous crosslinked epoxy resins, we changed crosslinking density (simultaneously with T g ) by just varying the ratio of the components and so this problem was avoided.…”

“…The only notable exception is macroscopic Shore hardness that is often applied for characterization of elastic crosslinked rubbers; the correlations between Shore hardness and macroscale elastic moduli are frequently quite strong [ 75 , 76 ]. Moreover, the authors usually investigate either stiff resins (i.e., thermosetting resins and/or vitrified networks below their T g [ 45 , 46 , 77 ]) or soft rubbers (i.e., elastic networks above their T g [ 74 , 75 , 76 ]). The correlations between T g and stiffness-related properties of those systems were usually weak, as the authors typically compared systems with different chemical compositions [ 46 ] and/or different amounts of various fillers [ 76 ].…”

Epoxy-based composites reinforced with imidazolium ionic liquid-treated aramid pulp

“…Treatment of the AP was performed in an ethanolic solution with 5 wt% of IL in relation to the AP mass, and followed previous reports [15][16][17][18]. The AP-IL mixture was placed in an ultrasonic bath at 50 • C for 30 min, left to evaporate the solvent for 24 h at room temperature and then placed in a vacuum oven for 12 h at 110 • C. The effectiveness of the treatment was assessed using scanning electron microscopy (SEM), thermal gravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR).…”

“…For instance, 1-n-butyl-3-methylimidazolium chloride (C 4 MImCl), 1-n-butyl-3-methylimidazolium methanesulfonate (C 4 MImMeS), 1-carboxymethyl-3-methylimidazolium chloride (HO 2 CC 1 MImCl), 1-triethyleneglycol monomethyl ether-3-methylimidazolium methanesulfonate (C 7 O 3 MImMeS) (Fig. 1) have been used to treat aramid for the preparation of styrene-butadiene rubber (SBR) [15,16], hydrogenated nitrile butadiene rubber (HNBR) [17], laminated epoxy-based composites [18] and also for bio-based rigid polyurethane foams [19]. Due to the contribution of the imidazolium cation π-cloud in π-π interactions and their hydrogen atoms (C 2 -H, C 4 -H, and C 5 -H) in hydrogen bonds with adjacent polymer matrix chains, these IL were considered promising compatibilizers.…”

Low-Temperature Carbonized Elastomer-Based Composites Filled with Silicon Carbide

“…Nitrile butadiene rubber (NBR) is one of the most widespread elastomers, characterized by low cost, high resistance to oil products and high resistance to thermal oxidative degradation. Due to its advanced properties, NBR is widely used as a matrix material in composites reinforced with carbon black [29,30], graphene [31], graphene oxide [32,33], SiO 2 [34], Al 2 O 3 [32] and other inorganic particles. There are some reports related to NBR-based materials' thermal degradation and aging at the temperatures less than 200 • C [35][36][37], whereas no data on the NBR carbonization behavior was observed.…”