Tribological Behavior of Polyurethane Immersed in Acidic Solution

Abstract

Polyurethane (PU) samples were immersed in a 1 M HCl solution for different durations from 0 to 90 days to investigate the influence of immersion time on the tribological performance of the samples. The effects of thermal, mechanical, and surface properties of the PU on its tribological performance were also investigated with respect to immersion time. It was found that the friction coefficient of the PU measured against a steel ball significantly decreased with increased immersion time due to the lubricating and cooling effects of absorbed water in the PU during the immersion. The decreased friction of the PU led to the improved wear resistance of the polymer, though the mechanical strength of the PU was reduced by the prolonged immersion due to the increased plasticization of the polymer. The experimental results clearly indicated that the immersion of the PU in the acidic solution for a certain period significantly influenced the tribological performance of the polymer.

Fine-scale tribological performance of zeolitic imidazolate framework (ZIF-8) based polymer nanocomposite membranes

“…4). Our results suggest that such debris function as "spacers" capable of suppressing damage caused by abrasive wear, by promoting free rolling and sliding contact mechanisms 27,28 under action of lateral forces. In summary, we have systematically investigated, for the first time, the micro-tribological behavior of a prototypical mixed matrix membrane comprising ZIF-8@Matrimid nanocomposites.…”

“…To this end, membranes containing higher nanoparticle content (i.e., more asperities) produce higher friction since a larger contact area is established between the two rubbing surfaces; this result is in line with previous studies (e.g., Refs. [25][26][27][28].…”

Multifunctional polymeric composites with wear-resistant, toughening, and self-healing features

“…Then, the HDI liquid released from the ruptured microcapsules flows into the wear track and covers it. Before curing, the released HDI liquid plays a role in lubrication to reduce the friction of the composite because it serves as a lubricant to lubricate the rubbing surfaces and as a spacer to prevent a direct solid-solid contact between the steel ball and composite [18,[32][33][34][35][36]. As the time goes on, the HDI liquid on the wear track of the composite and the steel ball reacts with the moisture in the environment to produce new polyurea materials [28].…”

“…Fiber reinforcements and solid or liquid lubricants are frequently applied to improve the wear resistance of polymers [16][17][18][19][20]. In most cases, external liquid lubricants can further improve the tribological properties of polymer-based composites compared to dry sliding [21,22].…”

Enhancing electrical and tribological properties of poly(methyl methacrylate) matrix nanocomposite films by co-incorporation of multiwalled carbon nanotubes and silicon dioxide microparticles

“…Therefore, the fabrication of conductive polymer matrix composites co-incorporated with multiwalled CNTs (MWCNTs) and silicon dioxide microparticles (SiO 2 -MPs) is particularly interesting, because the co-incorporation of MWCNTs and SiO 2 -MPs would be able to enhance the electrical networks formed by MWCNTs within the polymer matrix, which has not been reported yet. In addition, a high wear resistance of conductive polymer matrix composites is necessary for electronic devices made from them, in which worn composites can lead to an early failure of the devices [7][8][9]. Since the electrical conductivity and wear resistance of polymer matrix composites can be altered by the type, shape, dispersion and content of their fillers, a good understanding of a correlation between co-incorporation of MWCNTs and SiO 2 -MPs in polymer matrix composites and their electrical and tribological properties is important for their successful applications.…”