Sticky surface model

The fundamental nature of an adhesive bridge failure can be understood by building a model using adhesive smooth rubber strips as shown in Fig. 15.3(a). Three tapes were used to bridge a gap between two supports, overlapping the sticky surfaces together. 

For a surface with an array of sticky adsorption sites, such as in the case of the sticky site model, (SSM) model discussed elsewhere [56, 57, 58], the adsorption potential has the form... 

It is very important to note that the four cases noted above depend on both the type of graphite used and the solution composition. Highly reversible behavior and low irreversible capacity are achieved when the surface species formed are adhesive to the carbon surface (as described in terms of the sticky fingers model [119]), and cohesive. In addition, they should be formed at high enough potentials so that as the electrode reaches Li insertion potentials, it is already passivated, and hence, solvent co-intercalation is avoided. 

BASF s advertising model made from plasticized PVC in the 1960s has become sticky with time due to phthalate plasticizer at the surfaces. Dust from a nearby radiator has adhered to the hands and face. 

Whether bonded or physically adsorbed or embedded, surface polymers dangle from the polymer surface, as do the chains in any PDMS elastomer. Such chains are important with regard to mechanical properties such as adhesion, adhesion hysteresis, and tack ( stickiness ). Their rheological and dielectric behavior have been modeled using molecular dynamics. ... 

We start with the simplest model of the interface, which consists of a smooth charged hard wall near a ionic solution that is represented by a collection of charged hard spheres, all embedded in a continuum of dielectric constant c. This system is fairly well understood when the density and coupling parameters are low. Then we replace the continuum solvent by a molecular model of the solvent. The simplest of these is the hard sphere with a point dipole[32], which can be treated analytically in some simple cases. More elaborate models of the solvent introduce complications in the numerical discussions. A recently proposed model of ionic solutions uses a solvent model with tetrahedrally coordinated sticky sites. This model is still analytically solvable. More realistic models of the solvent, typically water, can be studied by computer simulations, which however is very difficult for charged interfaces. The full quantum mechanical treatment of the metal surface does not seem feasible at present. The jellium model is a simple alternative for the discussion of the thermodynamic and also kinetic properties of the smooth interface [33, 34, 35, 36, 37, 38, 39, 40]. 

Adhikari, B., Howes, T., Bhandari. B. R., Troung, V., 2003. Surface stickiness of drops of carbohydrate and organic acid solutions during convective drying Experiments and modeling. Drying Technol. 

Structure factor of the sticky hard sphere model. The structure factor of a system cf interacting spheres is determined by the inter-particle interaction potential u(r). We consider a system of hard spheres with adhesive surfaces. The pair-wise inter-particle interaction potential is written as ... 

Resins are thought to be molecular precursors of the asphaltenes. The polar heads of the resins surround the asphaltenes, while the aliphatic tails extend into the oil. Figure 13. Resins may act to stabilize the dispersion of asphaltene particles and can be converted to asphaltenes by oxidation. Unlike asphaltenes, however, resins are assumed soluble in the petroleum fluid. Pure resins are heavy liquids or sticky (amorphous) solids and are as volatile as the hydrocarbons of the same size. Petroleum fluids with high-resin content are relatively stable. Resins, although quite surface-active, have not been found to stabilize significantly water-in-oil emulsions by themselves in model systems. However, the presence of resins in solution can destabilize emulsions via asphaltenes solvation and/or replacement at the oil/water interface (89-96), Figure 13. 

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