Contact angle hysteresis, surface samples

This same technique should be helpful in understanding wetting properties important in the oil industry since wetting is very dependent on mineral surface energies. The use of contact angle hysteresis information may allow a better understanding of the effects of surface heterogeneities of natural mineral samples. The dynamic Wilhelmy plate technique is ideally suited for such experiments ... 

Contact-angle hysteresis measurements (performed with water) indicate, however, significant differences between PDMS samples, with an increase of hysteresis for PDMS B. Contact-angle hysteresis can be induced by a chemical or topological heterogeneity. However, the chemical composition of both PDMS samples is identical, and the surface roughness is low and also identical for both samples (close to... 

Table 9.4 shows solid surface energy data for the first PMTFPS sample listed in Table 9.3. Also included for comparison are PDMS from She et al. [18] and PTFE data taken from the compilation by Owen [19]. The She measurements are for a very thin film of PDMS, bonded to a smooth silicon wafer, that had very low contact angle hysteresis, only 3° difference between the advancing and receding water contact...

As lubricants, low-surface-tension perfluorinated liquids (e.g., DuPont Krytox oils) that are nonvolatile and are immiscible with both aqueous and hydrocarbon liquids can be used. Kim et al. (2012) reported the development of lubricant infosed structured surfaces fabricated on aluminum substrates. Polypyrrole was initially electrodeposited on the surface of aluminum samples, which was then followed by the subsequent fluorination of the structured coating and infiltration with lubricant. The resulting water contact angle measurements showed that these surfaces were characterized by low contact angle hysteresis (A0= str,R H7°-115° = 2°) and... 

Figure 9.11 Intrusion and extrusion MIP experiments. Extrusion curves illustrate ink-bottle pores where the mercury remains trapped in the sample. In this specific case, half of the intruded pore network can be considered as ink-bottle pores. The second pressurisation/depressurisation cycle shows a hysteresis attributed to a change in the contact angle between the mercury and the sample surface. (Adapted from Kaufmann, J. et a. . Journal of Colloid and Interface Science, 336, 730-737, 2009.)...

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