Water contact angles as a function

Fig. 9.10 Comparison of the formation and wetting behavior of the aliphatic HUT/DDT (a,c,e) and the aromatic HMB/MMB (b,d,f) mixed monolayer system on Au(lll). (a,b) Composition of the solution and surface composition of the resulting SAM. (c,d) Plot of the cos 6>= (7sv-7si)/7iv) of the advancing (and additionally in d) receding) water contact angle as a function of the surface OH concentration. The straight line represents the Cassie equation [104], in c) the grey line is calculated after the equation from Israelachvili [105] describing the contact angle on heterogeneous surfaces. (e,f)...

Water Contact Angles as a Function of the Mobile Counter-Anion Species... 

Fig. 6 Water contact angle as a function of substrate temperature. The substrate was exposed to high temperature for 5 min in laboratory air. Note the extreme stability of the DDMS monolayer in comparison to the OTS and octadecene monolayers.

Figure 4.2 Water contact angle as a function of chemical functionality on brush-covered surfaces. Brushes were grafted from ETFE via free radical polymerization. Brushes marked with an asterisk were obtained via postfunctionalization. Source. Adapted from Neuhaus et al. [2], with permission from John Wiley Sons Inc.

Figure 4.5 Advancing water contact angle as a function of ten erature on a PEO surface grafted with PNIPAAm [7]. Water contact angles steadily increase with teny>erature from the deflection of the curve, a LCST of 28 C can be derived. After cooling, a contact angle of about 50 was obtained (open symbol). Source Reproduced from Heinz et al [7], with permission from ACS.

Fig. 16 The stability of PPEGMA functionalized glass substrates indicated by the measured receding water contact angle as a function of mol% ATRP initiator (a) and brush thickness (b) upon incubation in cell culture medium at 37 °C. Adapted with permission from [149]. Copyright 2008 American Chemical Society...

Fig. 15 Water contact angle as a function of time under UV illumination for a polycrystalline Ti02 film on glass.

The stability of the surface wettability was studied by measuring the water contact angles at 24 h., 72 h., and 144 h. after the plasma treatment. There was a general increase in the water contact angle as a function of time after the plasma treatment. The rate of increase in the water contact angle as a function of time after the plasma treatment for the superhydrophilic surfaces was found to be significantly smaller (p < 0.05) than the hydrophilic surfaces (6 < 10°). 

Figure 3. Static water contact angle as a function of ODTS coverage on silicon as measured by SIMS peak area ratios. Symbol descriptions are given in Table I.

Fig. 12 Cassie model of equilibrium static sessile drop water contact angles as a function of TGP-H fiber surface coverage for FEP (gray) and PTFE (black) (Wood 2007)...

Fig. 4.20 (a) Representative SEM micrographs of square pillar array POTS surfaces and (b) plot of water contact angle as a function of pitch/width ratio of the pillar array surface (Reproduced with permission from [66], Copyright 2009 Elsevier)... 

Fig. 3. Dynamic contact angles as a function of water storage time (left) or drying time respectively (right).

Water ean usually be used as a unique solvent for the study of biomedical materials. In other applications such as reverse-phase liquid chromatography, however, different solvents such as water-methanol mixed solvents are used. As the MeOH fraction increases, the surface tension of the solution decreases. In mixed solvents, the trend of contact angles as a function of concentration was generally similar to that of the aqueous case. As the proportion of methanol increases, the contact angle deereases dramatically as in the case of decreased concentration. 

Water drops were formed at the mercury-benzene interface by means of a syringe, and the contact angle (measured in the water) was recorded as a function of time. For the interface between Hg and benzene saturated with water, y was measured independently as a function of time. The following table summarizes these data (all measured at 25°C) ... 

The grafting reaction is expected to take place in acidic aqueous media via acetaliza tion between OH groups on the EVA film and the CHO groups of the water-soluble DAS. In Fig. 23 the contact angle of the grafted film against water is shown as a function of time. A decrease in the contact angle, in other words, an increase in... 

FIGURE 2.13 Water contact angles on a tetrafluoroethylene (TFE)-methanol telomer wax surface as a function of roughness. Reprinted from Johnson and Dettre (1964) with permission. Copyright 1964 American Chemical Society. 

Fig. X-4. Water contact angle of titania-coated glass after treatment with trimethyloc-tadecylammonium chloride as a function of the number of coating treatments with 1.1% polydibutyl titanate. (From Ref. 51.)...

Fig. 5—The thickness and water-contact angle of PFAM thin film as a function of solution concentration.

Fig. 21—The thickness and water contact angle of FTE SAMs on the DLC surfaces as a function of the immersing time in a 10 mM FTE solution at temperature of 20°C (a) film thickness of FTE SAM, and (b) water contact angle.

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