Surface Forces, Surface Energy, and Adhesion of SAMs and Superhydrophobic Films

Abstract Expansion of a small spherical hole in a highly elastic solid is treated theoretically. Both elastic and surface energy terms are considered; the corresponding surface forces are assumed to be additive. The surface energy of the elastomer is assumed to be similar to that of simple liquids. Pressures or triaxial tensions required to inflate pre-existing holes to an indefinitely large size are calculated. Small holes require extremely large pressures, of the order of 1000 atm for holes of 10 A˚ radius. These results suggest a means of determining the distribution of hole sizes in elastomers and account, in principle, for experimental observations of cavitation processes. Detachment of the elastomer from a small rigid inclusion is treated in a similar way. The general absence of dilation or cavitation on stretching carbon black filled elastomers is thus accounted for solely in terms of the small size of these filler particles.

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Surface Forces, Surface Energy, and Adhesion of SAMs and Superhydrophobic Films: Relevance to Tribological Phenomena

Surfactants in Tribology, Volume 1 ◽

10.1201/9781420060089-14 ◽

2008 ◽

pp. 149-188

Keyword(s):

Surface Energy ◽

Surface Forces

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Direct Measurement of the Surface Energy of Corona-Treated Polyethylene Using the Surface Forces Apparatus

Langmuir ◽

10.1021/la00001a006 ◽

1995 ◽

Vol 11 (1) ◽

pp. 19-23 ◽

Cited By ~ 41

Author(s):

V. Mangipudi ◽

M. Tirrell ◽

Alphonsus V. Pocius

Keyword(s):

Surface Energy ◽

Direct Measurement ◽

Surface Forces ◽

Surface Forces Apparatus

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Decoration of specific sites on freeze-fractured membranes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081565 ◽

1978 ◽

Vol 36 (2) ◽

pp. 140-141

Author(s):

H. Gross ◽

H. Moor

Keyword(s):

Pure Water ◽

Freeze Fracture ◽

Chemical Properties ◽

Surface Forces ◽

Sulfate Pentahydrate ◽

Copper Sulfate Pentahydrate ◽

Physico Chemical ◽

Water Of Hydration ◽

Small Container ◽

Binding Forces

Fracturing under ultrahigh vacuum (UHV, p ≤ 10-9 Torr) produces membrane fracture faces devoid of contamination. Such clean surfaces are a prerequisite foe studies of interactions between condensing molecules is possible and surface forces are unequally distributed, the condensate will accumulate at places with high binding forces; crystallites will arise which may be useful a probes for surface sites with specific physico-chemical properties. Specific “decoration” with crystallites can be achieved nby exposing membrane fracture faces to water vopour. A device was developed which enables the production of pure water vapour and the controlled variation of its partial pressure in an UHV freeze-fracture apparatus (Fig.1a). Under vaccum (≤ 10-3 Torr), small container filled with copper-sulfate-pentahydrate is heated with a heating coil, with the temperature controlled by means of a thermocouple. The water of hydration thereby released enters a storage vessel.

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The annealed (0001) α-alumina surface and its influence on thin-film growth

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138051 ◽

1995 ◽

Vol 53 ◽

pp. 336-337

Author(s):

Michael W. Bench ◽

Paul G. Kotula ◽

C. Barry Carter

Keyword(s):

Electron Microscopy ◽

Surface Energy ◽

Film Growth ◽

Thin Film Growth ◽

Energy Calculations ◽

Transmission Electron ◽

Reflection Electron Microscopy ◽

Low Energy Electron ◽

Surface Nature

The growth of semiconductors, superconductors, metals, and other insulators has been investigated using alumina substrates in a variety of orientations. The surface state of the alumina (for example surface reconstruction and step nature) can be expected to affect the growth nature and quality of the epilayers. As such, the surface nature has been studied using a number of techniques including low energy electron diffraction (LEED), reflection electron microscopy (REM), transmission electron microscopy (TEM), molecular dynamics computer simulations, and also by theoretical surface energy calculations. In the (0001) orientation, the bulk alumina lattice can be thought of as a layered structure with A1-A1-O stacking. This gives three possible terminations of the bulk alumina lattice, with theoretical surface energy calculations suggesting that termination should occur between the Al layers. Thus, the lattice often has been described as being made up of layers of (Al-O-Al) unit stacking sequences. There is a 180° rotation in the surface symmetry of successive layers and a total of six layers are required to form the alumina unit cell.

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The nucleation of cavities at grain boundaries

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126299 ◽

1987 ◽

Vol 45 ◽

pp. 288-291

Author(s):

P. J. Goodhew

Keyword(s):

Surface Tension ◽

Surface Energy ◽

Grain Boundaries ◽

Radiation Damage ◽

Impurity Concentration ◽

Driving Force ◽

Nucleation And Growth ◽

Phase Boundaries ◽

Cavity Nucleation ◽

Spherical Bubble

Cavity nucleation and growth at grain and phase boundaries is of concern because it can lead to failure during creep and can lead to embrittlement as a result of radiation damage. Two major types of cavity are usually distinguished: The term bubble is applied to a cavity which contains gas at a pressure which is at least sufficient to support the surface tension (2g/r for a spherical bubble of radius r and surface energy g). The term void is generally applied to any cavity which contains less gas than this, but is not necessarily empty of gas. A void would therefore tend to shrink in the absence of any imposed driving force for growth, whereas a bubble would be stable or would tend to grow. It is widely considered that cavity nucleation always requires the presence of one or more gas atoms. However since it is extremely difficult to prepare experimental materials with a gas impurity concentration lower than their eventual cavity concentration there is little to be gained by debating this point.

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Influence of Fiber Surface Energy on Mechanical Properties of Sisal Fiber - Bio Based Epoxy Composites

JOURNAL OF POLYMER MATERIALS ◽

10.32381/jpm.2018.35.04.7 ◽

2019 ◽

Vol 35 (4) ◽

pp. 485-496

Author(s):

S. RAJKUMAR ◽

◽

R. JOSEPH BENSINGH ◽

M. ABDUL KADER ◽

SANJAY K NAYAK ◽

...

Keyword(s):

Mechanical Properties ◽

Surface Energy ◽

Fiber Surface ◽

Epoxy Composites ◽

Sisal Fiber

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Surface energy of cellulosic materials: The effect of particle morphology, particle size, and hydroxyl number

TAPPI Journal ◽

10.32964/tj14.9.565 ◽

2015 ◽

Vol 14 (9) ◽

pp. 565-576 ◽

Cited By ~ 1

Author(s):

YUCHENG PENG ◽

DOUGLAS J. GARDNER

Keyword(s):

Particle Size ◽

Surface Energy ◽

Particle Morphology ◽

Nanofibrillated Cellulose ◽

Particle Sizes ◽

Hydroxyl Number ◽

Small Individual ◽

Dispersion Component ◽

Commercial Applications ◽

Lower Temperature

Understanding the surface properties of cellulose materials is important for proper commercial applications. The effect of particle size, particle morphology, and hydroxyl number on the surface energy of three microcrystalline cellulose (MCC) preparations and one nanofibrillated cellulose (NFC) preparation were investigated using inverse gas chromatography at column temperatures ranging from 30ºC to 60ºC. The mean particle sizes for the three MCC samples and the NFC sample were 120.1, 62.3, 13.9, and 9.3 μm. The corresponding dispersion components of surface energy at 30°C were 55.7 ± 0.1, 59.7 ± 1.3, 71.7 ± 1.0, and 57.4 ± 0.3 mJ/m2. MCC samples are agglomerates of small individual cellulose particles. The different particle sizes and morphologies of the three MCC samples resulted in various hydroxyl numbers, which in turn affected their dispersion component of surface energy. Cellulose samples exhibiting a higher hydroxyl number have a higher dispersion component of surface energy. The dispersion component of surface energy of all the cellulose samples decreased linearly with increasing temperature. MCC samples with larger agglomerates had a lower temperature coefficient of dispersion component of surface energy.

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A new method for quantifying the blocking of coated paperboard

TAPPI Journal ◽

10.32964/tj9.5.29 ◽

2010 ◽

Vol 9 (5) ◽

pp. 29-35 ◽

Cited By ~ 2

Author(s):

PAULINE SKILLINGTON ◽

YOLANDE R. SCHOEMAN ◽

VALESKA CLOETE ◽

PATRICE C. HARTMANN

Keyword(s):

Surface Roughness ◽

Fatty Acid ◽

Surface Energy ◽

Film Thickness ◽

External Factors ◽

Additive Concentration ◽

Pressure Surface ◽

Fatty Acid Amides ◽

Coated Surfaces ◽

Definite Period

Blocking is undesired adhesion between two surfaces when subjected to pressure and temperature constraints. Blocking between two coated paperboards in contact with each other may be caused by inter-diffusion, adsorption, or electrostatic forces occurring between the respective coating surfaces. These interactions are influenced by factors such as the temperature, pressure, surface roughness, and surface energy. Blocking potentially can be reduced by adjusting these factors, or by using antiblocking additives such as talc, amorphous silica, fatty acid amides, or polymeric waxes. We developed a method of quantifying blocking using a rheometer. Coated surfaces were put in contact with each other with controlled pressure and temperature for a definite period. We then measured the work necessary to pull the two surfaces apart. This was a reproducible way to accurately quantify blocking. The method was applied to determine the effect external factors have on the blocking tendency of coated paperboards, i.e., antiblocking additive concentration, film thickness, temperature, and humidity.

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