Surfactants Nonionics

POLY-TERGENT S-LF Series (S-305LF, S-405LF, S-505LF)  

This wide-spectrum, low-foaming series of biodegradable alkoxylated linear alcohols finds use in such diverse areas as rinse aids and metal cleaning baths, and as foam depressants in hard surface cleaners. 

This line of moderate-foaming, biodegradable alkoxylated linear aliphatic alcohols is available with a broad range of cloud points. Members of this series remain liquid at room temperature and do not tend to form surfactant/water gels. They are used in various industrial and institutional applications, such as laundry and hard surface cleaning, where speed of solution and excellent emulsification are important. 

These low-foaming ethoxylated polyoxypropylene glycols of different molecular weights are designed to meet a variety of low-foam conditions. Members of this series find use as defoamers, dedusters and emulsifiers. They are used in rinse aids, machine dishwashing and laundry detergents as suds control agents. 

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Anionic surfactants Nonionic surfactants Cationic surfactants Amphoteric surfactants... 

Surfactants (nonionic)— polyethylene sorbitan monolaurate (Tween 20, Tween 80), pluronic, Triton, sodium dodecyl sulfate (SDS)... 

Interfacial thermodynamics Ionic surfactants Nonionic surfactants Surface tension Surface potential... 

The same effect is seen when a non—aromatic cationic surfactant/nonionic surfactant system is used. Since the nonideality of mixed micelle formation in this case is due almost entirely to the electrostatic effects and not to any specific interactions between the dissimilar hydrophilic groups, the geometrical effect just discussed will cause the EO groups to be less compactly structured... 

Anionic surfactant Cationic surfactant Nonionic surfactant... 

Surfactants can be divided into four general areas cationic surfactants, anionic surfactants, nonionic surfactants, and amphoteric surfactants. Major anionic surfactants are soaps, linear alcohol sulfates, linear alcohol ethoxy-sulfates, and linear alkylbenzenesulfonates. 

See Surfactants (Amphoteric), Surfactants (Anionic), Surfactants (Cationic), Surfactants (Nonionic). 

In MECC anionic surfactants are most frequently used, but cationic surfactants are also very popular. In addition, chiral surfactants, nonionic surfactants, zwitterionic surfactants, biological surfactants, or mixtures of each are finding increasing use. In all categories, variations in alkyl chain length will affect resolution or selectivity, as will changes in buffer concentration, pH, and temperature or the use of additives such as metal ions or organic modifiers. Typical surfactant systems used in MECC are shown in Table 5.3. 

Certain comb-type silicone surfactants have been shown to stabilize emulsions in the presence of salts, alcohol and organic solvents that normally cause failure of emulsions stabilized using conventional hydrocarbon surfactants and a study by Wang et al. [66,67] investigated the cause of this stability. Interaction forces due to silicone surfactants at an interface were measured using AFM. Steric repulsion provided by the SPE molecules persisted up to an 80% or higher ethanol level, much higher than for conventional hydrocarbon surfactants. Nonionic hydrocarbon surfactants lose their surface activity and ability to form micelles in... 

Nonionic surfactants consist of a -(CH2CH20)n0H or -OH as the hydrophilic group and exhibit a variety of hydrophile-lipophile balances (HLB) which stabilize O/W or W/O emulsions. Unlike anionic and cationic surfactants, nonionic surfactants are useful for oral and parenteral formulations because of their low irritation and toxicity. Based on their neutral nature, they are much less sensitive to changes in the pH of the medium and the presence of electrolytes. The best use of nonionic surfactants is to produce an equally balanced HLB of two nonionic surfactants one... 

The addition of a surfactant (nonionic, anionic, or cationic) to the same system resulted in a more complex zoo of structures [121]. Nonionic surfactants are... 

Two types of surfactant nonionics were considered. The nonyl phenol ethoxylates and the octyl phenol ethoxylates. These two types of surfactants were chosen as they are often encountered in agricultural formulations because of their respective efficiency. The results of the evaluation are giveji below ... 

Fig. 7.13 is a common example of a nonionic surfactant. Nonionic surfactants tend to adsorb onto surfaces with either the hydrophilic or the hydrophobic locations depending on the nature of the surface. 

FIGURE 21.2 Structures of some representative nonionic surfactants. Nonionic surfactants have either a polyether or a poly hydroxyl unit as the polar group. In the vast majority of nonionics, the polar group is a polyether consisting of oxyethylene units, made by polymerization of ethylene oxide (from Ref. 9). 

This material is a modified ethoxylated condensate type surfactant, nonionic in nature and exhibiting excellent compatibility and wetting efficiency in highly alkaline conditions. 

Typical surfactant templates for mesoporous silica (e.g., ionic surfactants, nonionic block copolymers) can be used for the synthesis of PMOs. PMOs can have different framework compositions depended on the precursor used. 

Methanol solution of liquid soap, which contains surfactants Nonionic and anionic surfactants (see Fig, 6.12). 

Amine oxides and sulfinyl surfactants (nonionics with a small head group)... 

Liquid cleaning compositions based on cationic surfactant, nonionic surfactant and nonionic polymer... 

The wash temperature has a significant effect on foaming due to its effect on the solubility of the defoaming surfactant. Nonionic surfactants are only effective above their cloud points. Careful consideration must therefore be taken when formulating with nonionics. Water hardness also plays a role in foam formation. In hard water, Ca2+ and Mg2+ form complexes with fats or anionic surfactants. These insoluble complexes interact with the foam, breaking up the micellar structure. 

The concentration at which this phenomenon occurs is called the critical micelle concentration (CMC). Similar breaks in almost every measurable physical property that depends on size or number of particles in solution, including micellar solubilization of solvent-insoluble material (Chapter 4) and reduction of surface or interfacial tension (Chapter 5), are shown by all types of surfactants—nonionic, anionic, cationic, and zwitterionic in aquecus media. 

The value of AGmic( CH2 -) obtained in this fashion falls in the range —(2.8-3.3) kJ[—(708-777)cal]/mol for all types of surfactants (nonionics, zwitterionics, uni- and divalent ionics), irrespective of the presence or amount of added electrolyte. 

Surfactants Nonionic Sorbitan esters Polysorbates Polyoxyethylene alkyl ethers Polyoxyethylene alkyl esters Polyoxyethylene aryl ethers Glycerol esters Cholesterol Anionic Sodium dodecyl sulphate Cationic Cetrimide Benzalkonium chloride... 

Surfactants (nonionics) Ethoxylated alkyl-phenols Ethoxylated fatty alcohols... 

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