Wetting speed

The speed of wetting has been measured by running a tape of material that is wetted either downward through the liquid-air interface, or upward through the interface. For a polyester tape and a glycerol-water mixture, a wetting speed of about 20 cm/sec and a dewetting speed of about 0.6 cm/sec has been reported [37]. Conversely, the time of rupture of thin films can be important (see Ref. 38). 

The values of Go and y are known and for the elastomer of Young s modulus of 2.1 MPa, [/o = 8 X 10 mm-s [12]. We can then evaluate 8 at ca. 20 mn. This value is perhaps a little high but of the same order of magnitude as earlier estimated [6]. Thus, despite some necessary approximations and simplifying hypotheses, we arrive at a semiquantitative explanation of the relationship between dewetting and therefore, presumably, wetting speed and the molecular structure of the elastomeric substrate. 

The molecular-kinetic theory predicts a maximum wetting speed vmax and a minimum dewetting speed vmin. At speeds larger than vmax gas bubbles form. This was indeed observed. For water this value is vmax 5 — 10 m/s. 

Cloud point over 212F aqueous 1% wetting speed Instant... 

A phosphated surfactant with excellent wetting speed. It is stable in caustic solutions. Also, it is of interest for its antistatic properties. 

TEX-WET 1002 possesses d making it effective in hard compatible with anionic and most of the usual types of cationic. It should not be TEX-WET 1002 possesses very excellent wetting speeds. 

TEX-WET 1070 has a rapid wetting speed performs as an excellent detergent has a cloud point above the boil has a moderate foaming action and is stable to 5-10% caustic soda. A suggested starting level for evaluation is 0.25%. 

Fig. 16-1 shows the technique for evaluating wetting speed by the standard Draves wetting test [9]. Wetting and scouring are normally associated as being... 

At very low wetting speeds, the triple-phase line moves erratically with stick - slip movement, thereafter the angle increases continually with speed for the advancing line... 

To characterize the effect of the functionalization of the NR phase on CB localization, a 50/50 SBR/ENR 50 blend was prepared and investigated, and compared with the behaviour of the SBR/NR blend. It was found that the wetting speed of the investigated rubbers increases according to the order... 

The effect of the molecular weight of NR (NO, N1 and N2) on the phase-specific CB localization in the SBR/NR blend is shown in Figure 6.15(b). In the first mixing process, the NR phase with lower viscosity can wet CB faster than that with higher viscosity. This behaviour is in agreement with Equation (6.34), which shows that the wetting speed b increases with decreasing matrix viscosity. In the subsequent period, the viscosity seems not to affect the CB relocalization. 

KARA WET LOG is a concentrated nonionic wetting agent which may be used in a multitude of applications on both natural and synthetic fibers. KARA WET LOG obtains wetting speeds which are comparable to many of the fastest wetting anionic products. Clear, colorless liquid Activity 90% pH of 5% solution 6.2 Weight per Gallon 8.31 pounds Stability Indefinite... 

FIGURE 42.7 Wetting speeds for three common solder alloys at 235°C. 

Due to the lower wetting speeds associated with alternative lead-free solders, flux activation will be a critical factor in paste performance. No-clean and water-washable solder pastes are being designed so they do not require nitrogen reflow and can produce reliable solder connections with good wetting in air. Water-washable solder pastes with their higher concentration of activators will solder most metal finishes adequately. No-clean solder pastes require careful finish and paste attribute selection. 

Features Minimizes buildup from hardness and silicates high caustic stability precipitation of calcium and magnesium complexes formed in scouring and bleaching prevents reduction in wetting speeds from build-up of hardness in saturators Properties Lt. yel. liq. sp. gr. 1.3 dens. 10.84 Ib/gal pH (5%)7-9 Storage May freeze < 20 F allow to thaw completely R.T. before use Hipochem SS-400 [Boehme Filatexe]... 

In spite of the complexity of the problem some progress has been achieved in various theoretical studies 7l while careful experimental observations have also been undertaken 72,73 at low and high wetting speeds. 

Solder wetting speed Slow Intermediate Fast... 

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