Clouding detergency

Sodium lauryl sulfate is available in solution, paste, and soHd forms. As a solution its activity ranges between 28—30%, and as a paste it is 55% active. With this detergent in a shampoo, inorganic salts can affect viscosity. In addition, the limited solubiHty of sodium lauryl sulfate requires its judicious use in low cloud point clear shampoo systems. 

As the temperature of dilute aqueous solutions containing ethoxylated nonionic surfactants is increased, the solutions may turn cloudy at a certain temperature, called the cloud point. At or above the cloud point, the cloudy solution may separate into two isotropic phases, one concentrated in surfactant (coacervate phase) and the other containing a low concentration of surfactant (dilute phase). As an example of the importance of this phenomena, detergency is sometimes optimum just below the cloud point, but a reduction in the washing effect can occur above the cloud point (95). However, the phase separation can improve acidizing operations in oil reservoirs (96) For surfactant mixtures, of particular interest is the effect of mixture composition on the cloud point and the distribution of components between the two phases above the cloud point. 

It is used in org synthesis and as solvent when added to colloidal systems such as detergents and wetting agents of limited water soly, permits w dilution while reducing, without gelling or clouding. Its toxicity is discussed in Ref 3, p 306 Refs 1) Beil 1, 468, [519] 12078 ] 2) A. 

Because the sarcosinates have the ability to raise the cloud point of nonionic surfactants, this feature can be used to advantage in the formulation of dishwasher rinse aids. At the cloud point and up to 15C above it, foam generation is reduced and detergency is enhanced. By adjusting the cloud point of the formula to the use temperature, one can take full advantage of this performance feature. 

CjiEOj is present as a W+L dispersion between 0 and about 30 °C (it does not exhibit a cloud point), and undergoes a transition to a W+L2 system above 30 °C. A comparison of the detergency performance of the lamellar phases of C12E03 and C,2E04 can be made at 30 °C. At 48 °C, the performance of the very hydrophobic phase can be compared with that of the La phase of C12E04 and the Ll phase of C12E03. 

Any species that enhances the solubility of another. Example hydrotropes such as alkyl aryl sulfonates (e.g., toluene sulfonate) are added to detergent formulations to raise the cloud point. 

Another form of clouding that may be caused indirectly by the perfume is sometimes observed in water-detergent systems such as foam baths, shampoos, or dishwashing detergents. This, paradoxically,... 

In Figure 2 the clouding points of different oils are shown in dependence of pressure at 50°C. For simplicity the oils of different producers and applications are termed by the capitals A-F. The main characteristics of the oils are presented in Table 1. In addition to the different composition of their hydrocarbon content the oils contain a variety of additives, e.g. aging inhibitors, anticorrosives, detergents, pourpoint depressants, foam inhibitors and others. 

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%. 

In formulating detergents and scouring agents for textile wet processing, TEX-WET 1140 is a very economical, non-flammable cloud point depressant. 

Hydrotropes are often added to an LDLD to help solubilize certain surfactants or other materials that are not easily soluble in water to ensure the stability of the formulation. The fundamental properties of hydrotropes and their hydrotropic action in liquid detergents are discussed in Chapter 2. The addition of a hydrotrope affects the formula viscosity and cloud/clear points. 

The fluorescence reading at this point is taken to be the maximal fluorescence (Tmax). It can be difficult to solubilize DNA/liposome aggregates with Triton X-100, but heating the samples to the cloud point of the detergent (about 100°C) (104) followed by vortex mixing helps. 

As mentioned above, maximum oily soil removal from polyester substrates by POE nonionics is obtained when the PIT of the surfactant in the presence of that soil is close to the wash temperature. Since the PIT decreases with decrease in the EO content of the POE nonionic surfactant, it is to be expected that as the wash temperature is decreased, the EO content of the surfactant showing optimum oily soil removal will decrease. Thus, for single homogeneous surfactants, C12H25 (OC2H4)vOH, maximum cetane detergency at 30°C was shown by the 4EO compound (PIT = 30°C), at 50°C by the 5EO compound (PIT = 52°C), and at 65°C by the 6EO compound (Benson, 1986). The detergency of the 5EO compound at 30°C could be increased by additives that decreased its cloud point (and PIT). 

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