Surfactants foams

There are many laboratory methods for testing the relative merits of one defoamer against another. It is a simple matter to measure foam height as a function of time to compare the performance of various foam surfactants and defoamers. Unfortunately, this simplicity has led to a wide variety of methods and conditions used with no standard procedure that would make the measurement of foaminess as characteristic of a solution as its surface tension or viscosity. It has been suggested that the time an average bubble remains entrapped ia the foam is such a quantity (49), but very few workers ia the defoamer iadustry have adopted this proposal. Ia practice, a wide variety of methods are used that geaerally fall iato oae of five maia categories ... 

Alcohol sulfates are excellent foaming surfactants. According to the Kitchener and Cooper classification [148], alcohol sulfates form metastable foams. However, quantitative values cannot easily be compared because foam largely depends not only on the instrument used to produce and evaluate foam but also on the concentration of surfactant, impurities, temperature, and many other factors. In addition, a complete characterization of the foam capacity should take into account the initial amount of foam, its stability, and its texture. 

The foam volume and stability of alcohol sulfates is relatively increased in hard water compared to soft water. The amount and quality of foam is dependent on the alkyl length. Sulfates with C12-C,4 alkyl chains produce the richest creamy foam with small bubbles. C8-C10 alcohol sulfates are foam depressants and C16-C18 alcohol sulfates are poor foaming surfactants. Foams produced by alcohol sulfates are also relatively stable in the presence of sebum. Sodium and ammonium alcohol sulfates foam better than triethanolamine alcohol sulfates. Alcohol ether sulfates produce lighter foams than those of alcohol... 

Chlebicki and Slipko [127] determined the foam ability of sodium propoxyl-ated alcohol sulfates by the Ross-Miles method. These substances are low-foaming surfactants the greatest foam height was observed for dodecyl and tetradecyl chains. As expected, as the number of polyoxypropylene units on the same alcohol chain increases, foam height decreases. The maximum foam height obtained was 225 mm for a 2 g/L solution of sodium tetradecyl (1 PrO) sulfate. 

The sodium salt of tall oil acid is suitable as a foam surfactant. Experimental results show that sodium tallates are effective foaming agents that can produce pressure gradients of hundreds of pounds per square inch (psi) per foot in a sandpack [1373]. 

W. T. Osterloh and M. J. Jante. Low-cost foam surfactant from wood pulping by-products. In Proceedings Volume, volume 2, pages 191-199. 8th EAPG Impr Oil Recovery Europe Symp (Vienna, Austria, 5/15-5/17), 1995. 

Choose nonionics as suds stabilizers for use with foaming surfactants that are ionic. Prefer those with higher ability to lower the critical micelle concentration (CMC) of the foaming surfactant. 

Alcohol sulfates (AS) are usually manufactured by the reaction of a primary alcohol with sulfur trioxide or chlorosulfonic acid followed by neutralization with a base. These are high foam surfactants but they are sensitive to water hardness and higher levels of phosphates are required. This latter requirement has harmed the market for this type of detergent, but they are 2% of production for the major household surfactant market. Sodium lauryl sulfate (R = Cn) is a constituent of shampoos to take advantage of its high-foaming properties. 

R. D. Kulkarni, E. D. Goddard, and P. Chandar, in Prud homme, ed., Foams, Surfactant Science Series 57, Marcel Dekker, Inc., New York, 1996,... 

For spray cleaners, low foam surfactant required. Must be... 

Reservoir-foam applications may involve slug injection, in which foaming surfactant solution is injected into the gas stream at the well-head over a period of a few hours, semi-continuous injection, in which surfactant solution is injected at intervals over a period of a day or so, and continuous injection, in which surfactant solution is injected continuously for months or even years. Recently, much attention has been paid to near-well applications of foams [345,726-728],... 

A separation method in which a component of a liquid preferentially adsorbed at the liquid-gas interface is removed by foaming the liquid and collecting the foam produced. Foaming surfactants can be separated in this manner. 

Sometimes, the developer of surfactant products is compelled to use high foaming surfactants for applications in which only little foam is acceptable, e.g. in detergency and, in these cases, antifoams are necessary. Antifoams are substances or mixtures of substances which are able to reduce the foaming tendency of a system or destroy an existing foam when added in... 

The three component streams are in a recycle mode at the desired flow rates before foaming. During foaming, surfactant and precursor are premixed before they come in contact with the polyisocyanate in the power mixer. The foaming mixture is then discharged through multiple nozzles in the spreader (Figure 5). 

Fig. 7.7. Histogram of the distribution by size (diameters) of foam films in the foam surfactant, NaDoS...

Low foaming surfactant and dyeing assistant for all textile fibers to be dyed in jet equipment. 

Very low foam surfactant and scouring agent for all textile fibers. Especially suitable for pressure and jet equipment. 

Same applications as TRITON X-100 but a lower foaming surfactant. ... 

Surfactants. A surfactant is a major raw material for polyurethane foams. Surfactants play an important role in obtaining required cell structures, e.g., fine cells, coarse cells, closed cells, and open cells, and these cell structures then influence foam properties. 

Use Alkyd resins, rosin esters, urethane coatings and foams, surfactants, lubricating oil additives. 

Use High-foaming surfactant for viscosity control and detergent action in cosmetic and industrial cleansers. 

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