Foaming additive effect

Cocamide DEA (or MEA or TEA) is used as a foaming agent, to make lather. The other surfactants generate a certain amount of suds, but this foaming agent is added to get the amount just right. In addition to its foam-stabilizing effects, it is also a viscosity booster—it s thick. 

The foam-negative effects of lipids can also be counteracted with the addition of a lipid-binding protein, wheat puroindoline (PIN), to beer. The PIN may bind the residual free lipids in such a way that they can no longer destabilize the foam. (Adapted from Cooper et ah, 2002)... 

Because of its distinctive algicidal and slimicidal effects Benzalkonium chloride formulations may be used for the treatment of cooling and swimming pool water. However, the foam promoting effect of Benzalkonium chloride even at low concentrations (20 40 mg/1) sets limits to this application. Recommended addition rates are 2-10 mg/1. 

Ida et. al. (17) have postulated that the effect of surface-dilational viscosity (18,19) is not negligible in the motion of a small bubble when anti-foaming additive is added to base oil, and this effect is more dominant when initial bubble radius is small. This effect restrains the natural vibration of bubbles, and delays the transient response under sudden decompression. 

Foaming is sometimes unwelcomed in syrups, fruit concentrates, soft drinks, vegetable oHs, tea and coffee extracts and in many other commodities. Reduction of foaming in these cases can be achieved by adding certain substances to cause the coUapse of the foam. Their effect depends on their tendency to form a monomolecular film on the surface, which destabilises the foam. Often these substances reduce the surface tension of the Hquid phase to the threshold value at which the bubble walls are so thin that they burst. Commonly used additives are silicone oils in concentrations of 10-100 mg/kg and also primary fatty alcohols, fatty amides, fatty acids and their esters. 

Nanotoughening is an effective method to increase the fracture toughness of polymeric foams. Additionally, the nanoclay layers introduced additional crack deflection and microcracking. The intensity of the crack deflection increased with the size of the nanoclay agglomerates. 

Naguib, H. E., C. B. Park, and S. W. Song. 2005. Effect of supercritical gas on crystallization of linear and branched polypropylene resins with foaming additives. Ind Eng Chem Res 44 6685-91. 

The iso-alpha acids have tensioactive properties which stabilize beer foam. This effect was discovered in 1916 (94) and has been confirmed repeatedly (95-101). In particular, complexes of the iso-alpha acids with some metal ions are important (102). The concentration of the iso-alpha acids in the foam head is always higher than in the bulk of the beer, but when nickel(ll) ions are added this effect is enhanced (103,104). Also, there is a clear relationship between the stability of the beer foam after addition of nickel(ll) ions and the iso-alpha acids content of beer (105). It has been shown that cobalt(ll) ions increase the foam stability (106). Other metal derivatives of the isohumulones are less active in this respect (107). Furthermore, nickel(ll) ions may be... 

Oily additives are used in various technologies (e.g., paper and pulp production, ore flotation, fermentation) and commercial products (detergents, paints, some pharmaceuticals) to avoid the formation of an excessive foam, which would impede the technological process or the product application [1-3]. In other cases (oil recovery and refinement, shampoos, emulsions for metal processing machines) oil drops are present, without being specially introduced for foam control, and can also affect the foamability of the solutions. Small fractions of hydrophobic solid particles of micrometer size, such as hydrophobized silica or alumina, plastic grains, or stearates of multivalent cations, are often premixed with the oil because the solid-oil compounds obtained exhibit a much stronger foam destruction effect than the individual components taken separately [4-8]. Such oily additives are termed antifoams in the literature and can be based on hydrocarbons, poly-dimethylsiloxanes (PDMSs, silicone oil) or their derivatives [1,4]. 

Additives have the same effect on thermoplastic foaming processes as on thermoset foaming processes. Environmental conditions are important in this case because of the necessity of removing heat from the foamed stmcture in order to stabilize it. The dimensions and size of the foamed stmcture are important for the same reason. 

Other. Because a foam consists of many small, trapped gas bubbles, it can be very effective as a thermal insulator. Usually soHd foams are used for insulation purposes, but there are some instances where Hquid foams also find uses for insulation (see Eoamed plastics Insulation, thermal). Eor example, it is possible to apply and remove the insulation simply by forming or coUapsing the foam, providing additional control of the insulation process. Another novel use that is being explored is the potential of absorbing much of the pressure produced by an explosion. The energy in the shock wave is first partially absorbed by breaking the bubbles into very small droplets, and then further absorbed as the droplets are evaporated (53). 

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