Roles of paper composition and humidity on the adhesion between paper sheet and glass: a molecular dynamics study

Abstract

Understanding adhesion behavior between paper materials and inorganic substrate is important to minimize surface contamination by paper fragments. In this work, we investigate adhesion mechanisms between paper sheet and glass in terms of molecular interaction. Molecular dynamics simulations are employed to calculate adhesion force between paper sheet and the silica glass surfaces. Pulling and sliding tests are simulated to find the effects of the paper compositions such as mannan, glucan, and glucuronoxylan and humidity on the adhesion. Simulation results reveal that crystalline cellulose film of mannan unit (uni-directional hydroxyl groups) shows higher adhesion than that of glucan unit (bidirectional hydroxyl groups). Also, addition of just a few glucuronoxylan (xylan) hemicellulose molecules on the cellulose film remarkably enhances adhesion force, because of carboxylic acid groups with strong polarity in xylan. In addition, introduction of humidity leads to a further increase of adhesion due to hydrogen bonds bridged by water molecules. The adhesion force is maximized around 10 H2O/nm 2 because as the humidity increases, hydrogen bond interactions are saturated, whereas the Van der Waals interactions decrease due to thicker water layer. It is discussed that consideration of the capillary force for paper may result in different adhesion response that reflects more realistic situation.

Particle Size and Humidity Effects on Nanocellulose Adhesion to Glass: Implications for Mitigating Particulate Contamination in Industrial Processes

“…Here, an additional contribution critical to the adhesion force in ambient conditions�especially at intermediate humidity (40−50% RH)�is the change in the structure of the adsorbed water layer. In prior work, an increase of adhesion force was repeatedly observed at intermediate RH, [9][10][11]15 followed by a decrease in adhesion force as the RH gradually increased until saturation. It has been suggested 9,11 that, during the formation of the first adsorbed water layer, the hydrogen bonds that bridge the sphere−plane interface are stronger than the hydrogen bonding between water molecules comprising the bulk liquid.…”

“…In prior work, an increase of adhesion force was repeatedly observed at intermediate RH, [9][10][11]15 followed by a decrease in adhesion force as the RH gradually increased until saturation. It has been suggested 9,11 that, during the formation of the first adsorbed water layer, the hydrogen bonds that bridge the sphere−plane interface are stronger than the hydrogen bonding between water molecules comprising the bulk liquid. It follows that the surface tension 15 and the hydrogen bonding distribution 17 of the adsorbed water layer at low to intermediate RH may deviate from that of bulk liquid water.…”

“…For substrates that are non-porous and do not bond with particles via mechanical locking and inter-diffusion, that is, glass, the interfacial adhesion forces in ambient environmental conditions include the van der Waals force, electrostatic force, and capillary force arising from the presence of the condensed water meniscus. , Adhesion mechanisms involving particulates onto planar surfaces have been extensively studied using either molecular dynamic simulation − or atomic force microscopy (AFM); − however, the majority of studies assumed that the water meniscus and van der Waals forces together govern the interfacial interactions, while the electrostatic force is relatively weak and thereby negligible. , More recent studies have shown that the force due to electrostatic charging could be comparable in magnitude to the forces from van der Waals interactions and the capillary “water bridge” formed in humid environments. Also, the adsorption isotherm of water has not previously been considered in the theoretical calculation of the meniscus force.…”

Water Adsorption Isotherm and Surface Conductivity of Boroaluminosilicate Glasses

“…Glass surface science is of significant importance in both academic research 1−6 and industrial development 7−11 of various physical and chemical processes including aqueous corrosion, 12−16 crack/flaw generation/propagation, 17−21 and particle adhesion. 6,22,23 Flat panel display industries use glass substrates for thin-film transistors on panel devices in which electrostatic charging can directly impact downstream manufacturing. 24−26 Process problems associated with surface charging have grown more challenging in recent years due to decreasing pixel dimensions of ultrahigh-density displays.…”

“…Glass surface science is of significant importance in both academic research − and industrial development − of various physical and chemical processes including aqueous corrosion, − crack/flaw generation/propagation, − and particle adhesion. ,, Flat panel display industries use glass substrates for thin-film transistors on panel devices in which electrostatic charging can directly impact downstream manufacturing. − Process problems associated with surface charging have grown more challenging in recent years due to decreasing pixel dimensions of ultrahigh-density displays . Moreover, the surface charge electrostatically attracts particles to the glass surface during manufacture or fabrication. , Such adhesion of airborne particles can cause interference with the alignment of structural patterns and device failure leading to overall yield loss. − Therefore, understanding the charging mechanisms of flat panel display-type glasses is important because it can help identify strategies for minimizing or eliminating surface charging, which can ultimately lead to improved device performance and yield.…”