Swellable elastomeric HNBR–MgO composite: Magnesium oxide as a novel swelling and reinforcement filler

The mechanical properties of a model hydrogenated nitrile butadiene rubber (HNBR) following simulated sweet oil exposure at elevated temperature and pressure

“…A possible explanation for this behaviour is that some of the test solvent mix absorbs into the HNBR in the early stages of exposure, but the increasing crosslink density due to material ageing over time prevents these chemicals from diffusing out of the HNBR after it has been removed from the test solvent mix. Another possible contribution to this residual mass increase could be from water becoming chemically bound to, or physically entrapped in, the MgO filler, as reported by Han et al [25]. The general reduction in drying rate with increasing degree of ageing suggests that increasing crosslinking restricts the mobility of the absorbed solvent, leading to slower movement of solvent through the HNBR to the surface where evaporation can occur.…”

The effect of hydrocarbon ageing on the mechanical properties, apparent crosslink density and CO2 diffusion of a hydrogenated nitrile butadiene rubber (HNBR)

“…It is also assumed that the non-HNBR component of the compound Table 1) to be inert with respect to swelling behaviour. Although magnesium oxide is reported to yield swelling effects due to hydration in HNBR [26], the 10 phr MgO present in this formulation (see Table 1), equivalent to a weight fraction of ca. 5% (volume fraction of ca.…”

Controlling the mechanoadaptive properties of hydrogenated nitrile rubber by the incorporation of cementious based industrial waste for downhole application

“…The reaction between the matrix and filler can be confirmed from the FTIR study, which upholds the signatures of the conversion of cyanide (CN) group to carboxylate group. [ 18,22,27 ] It is observed that the cyanide (CN) peak at 2236 cm −1 is diminished and the peak near 1500 cm −1 broadens due to the interaction of COO − anionic species with Ca 2+ of the cementitious material on the hydrothermal treatment of the composite for 28 days. [ 19,40 ] This is due to the hydrolysis of the CN group (Supporting information, Figure S4).…”

“…Composites made out of cementitious materials with polymers can have significant applications in numerous fields where water swellable polymers are largely used as a sealing material. These water swellable polymers find application in areas such as in microfluidic valves [ 18 ] for flow control [ 19,20 ] and sealing of joints used in the oilfield industry. [ 21,22 ] In such applications, these materials are usually placed in between the annulus of the casing and the rock formation, which prevents any fluid leakage by increasing in volume after getting swelled in brine or water [13,19,23 . ]…”

“…Interestingly, we have found that FA and SG also improvise to the postpolymerization modification of the rubber matrix serving as reactive filler in a mechanism similar to that reported for WC based composite and has been confirmed by Fourier transform infrared (FTIR) analysis. [ 18,19,37,38 ] The changes in cross‐link density, hardness, elastic modulus, mass, and volume upon repeated dry and wet cycles was investigated. The morphology and microstructure analyses were performed using X‐ray diffraction (XRD), atomic force microscopy (AFM), field emision scanning electron microscopy (FESEM), and X‐ray scattering (SAXS) analyses.…”