Friction at nanopillared polymer surfaces beyond Amontons’ laws: Stick-slip amplitude coefficient (SSAC) and multiparametric nanotribological properties

Critical Review of Nanopillar-Based Mechanobactericidal Systems

“…The frictional behavior of nanostructured surfaces is highly influenced by the surface-specific parameters such as surface roughness parameters, 89 nanofeature geometries, and their densities. 90 In this light, studying nanostructured surfaces exhibiting different frictional behaviors and correlating it with their bactericidal performance could give new insight into optimization of the mechanobactericidal surfaces.…”

“…These sharp spikes can present a lateral force, contributing to the disruptive action of nanoscale features on the bacterial cell wall influencing the bacterial stress response that could manifest in turgor pressure fluctuation and ROS production. The frictional behavior of nanostructured surfaces is highly influenced by the surface-specific parameters such as surface roughness parameters, nanofeature geometries, and their densities . In this light, studying nanostructured surfaces exhibiting different frictional behaviors and correlating it with their bactericidal performance could give new insight into optimization of the mechanobactericidal surfaces.…”

Insights into complex nanopillar-bacteria interactions: Roles of nanotopography and bacterial surface proteins

“…The first step involves preparation of the master mould using a two-step anodisation technique and the second step involves transfer of the pattern onto the polymer substrate using a hot-embossing technique. Details of both the anodisation and hot-embossing processes are described elsewhere [29]. Briefly, an aluminium foil with a 5 mm thickness (99.9999% purity, Goodfellow) was washed with deionised (DI) water, ethanol (99.6%, Fischer Scientific) and acetone (analytical reagent grade (99.99%), Fisher Scientific) to remove grease before being electropolished in a 1:4 (v/v) perchloric acid (60%, extra pure, Fisher Scientific)/ethanol (analytical reagent grade (99.99%), Fischer Scientific) at 7 o C for 2 min at a current density of 0.1 mA mm -2 .…”

“…1): blunt and wide nanopillars (BWN) that closely mimic the nanopillars found on Psaltoda claripennis wings, which are 70 nm in diameter, 256 nm in height and 122 nm in pitch distance (density of 67 nanopillars per 𝜇m 2 ) [35]; blunt and dense nanopillars (BDN) that have the same diameter as BWN but with approximately twice the density (120 nanopillars per 𝜇m 2 ); sharp and dense nanopillars (SDN) that have the sharpest nanopillar tip with a diameter of 40 nm but the same density of nanopillars as the BDN surface. The surface roughness, wetting and nanotribological properties of the nanopillared surfaces have been reported in our previous study [29] and are also summarised in Table S2 (Supplementary Information).…”

Study on the microcosmic superlubricity mechanism of PVPA affected by metal cations

“…For example, the microstructure, roughness, and surface charge of the polymer can affect the frictional properties of the polymer at its surface [34][35][36]. Some scholars pointed out the existence of a strong correlation between friction and adhesion, indicating that depending on whether there is adhesion force constituting the normal force between the surface and interface, a higher or lower friction coefficient is obtained between the tribo-pairs [37][38][39][40]. When using the AFM colloidal probe to study the specific effect of adhesion on friction, some studies have also found that the adhesion between spherical probe and polymer coating is attributed to the contribution of van der Waals interaction, electrostatic interaction, hydrogen bond, etc.…”