Applications foams

The market is dominated by flexible foam applications (43% in the United States) and rigid and semi-rigid foam (29%). Cast elastomers (4%) and RIM elastomers (3%) have only specialised outlets. The remaining sizeable 21% of the market cover such diverse uses as thermoplastic rubbers, surface coatings, adhesives, sealants and synthetic leathers. 

Good thermal stability is a requirement for surfactants used in processes to enhance oil recovery. This applies most particularly to steam foam applications where surfactants such as AOS may be exposed to temperatures far above 100°C albeit for short times. Many authors have approached the problem of the thermal stability of a surfactant through a determination of the activation energy of the thermal degradation process. Once the activation energy is known, it can be used to estimate the rate of thermal degradation under various conditions. 

A. Razzaq. Characterization of Surfactants in the Presence of Oil for Steam Foam Applications. PhD thesis, Stanford Univ, 1992. 

A. Razzaq and L. M. Castanier. Characterization of surfactants in the presence of oil for steam foam application. US DOE Fossil Energy Rep DOE/BC/14600-37, Stanford Univ, 1992. 

Application is mainly by padding followed by curing at 150-180 °C, although minimum add-on techniques such as slop padding, spraying and foam application have been successful. They can also be applied by discontinuous methods, such as exhaust or dip-spin [501]. 

Tank Type II surface foam application. Foam to Tank NFPA 11-3.2.4 200 330 NFPA 11-3.2.8.2,1 hose, 50... 

Special alcohol resistant (or compatible) type foam is needed for application to alcohols, esters or ketones type liquids and organic solvents, all of which seriously break down the commonly used foams. Commercially available foam products are now available that can be used on both alcohols and hydrocarbons, only alcohols or only hydrocarbons. It is therefore imperative to design foam systems in a cost effective fashion if several products are in use that may require special foam application requirements. 

The European Parliament has adopted phase-out dates for the use of HCFCs in rigid foam applications which are basically in line with those in the USA and Japan. From 1 January 2000, the use of HCFCs for integral skin PU and PE foams is prohibited. From 1 January 2002, the use of HCFCs in expanded PS foams is prohibited. From 1 January 2003, the use of HCFCs in flexible-faced PU foam laminates, appliances and sandwich panels is prohibited. EUROPEAN PARLIAMENT... 

Foam systems have more components requiring higher maintenance and have somewhat lower reliability than water-only systems. Low expansion foam systems do offer the advantage over high expansion foam of an effective "water only" discharge after the foam agent has been expended. "Water only" discharge can be detrimental in most situations that require foam application. Limitations on the use of foam include ... 

The system can be operated with fewer emergency responders and foam loss is minimized. Foam chambers cause the foam to flow down the tank shell and onto the liquid surface therefore, thermal updrafts have little effect on foam application. A similar effect is seen with the use of foam chambers to protect the seals on floating roof tanks. 

The circumference of the tank will determine the number of points needed for foam application. The maximum spacing between chambers should be 40 ft (12 m) measured around a tank s circumference using a 12-in (30-cm) high dam and 80 ft (24 m) measured around the tank circumference using a 24-in (61 -cm) high dam. 

Foam Application Time—Chambers and Subsurface Methods... 

The foam concentrate used with subsurface systems should be a fluoroprotein type for best results, although some AFFF foams are listed for substitutable application (because of their "fuel shedding" properties). The minimum foam solution rate should be 0.3 gpm/ft (12 Ipm/m ). The supply of foam liquid should be adequate to operate the system for 20 minutes. The foam injection point must be above the level of any residual water in the bottom of the tank. Subsurface foam application is not recommended for open or covered floating roof tanks or cone roof tanks with internal floating covers. 

The minimum stored supply should permit foam application at recommended rates for the periods of time indicated in earlier sections for tanks and portable applications. 

Fixed active fire protection systems incorporating both water spray and foam application... 

A means of foam application to the tank in the proper amount and proportion... 

Also, less time is required to prepare for foam application, resulting in faster extinguishment, especially for numbers of closely spaced tanks up to about 50 ft (15 m) in diameter. Foam monitors are effective in fighting large spill fires, such as those in tank impounding basins. However, industry experience indicates that foam monitors and foam hose streams are ineffective in fighting tank fires in water-soluble materials. It has been determined that foam is only effective on these materials if applied very gently by fixed application devices or hand hose. 

Brookfield, Ct., 2002, Session I, p.9-18, 27cm, 012 NOVEL HIGH MELT STRENGTH POLYMERS FOR FOAM APPLICATIONS Mispreuve H Chaudhary B I Thoen J Dow Chemical Co. 

Foams 2000 Second International Conference on Thermoplastic Foam. Conference proceedings. Parsippany, N.J., 24th-25th October 2000, p. 139-48 USING POLYMER CHARACTERISATION TECHNIQUES TO PREDICT LDPE RESIN SUITABILITY FOR EXTRUDED FOAM APPLICATIONS Anger J Ngnyen L Nova Chemicals Corp. 

Patent Number US 6103775 A1 20000815 SILANE-GRAFTED MATERIALS FOR SOLID AND FOAM APPLICATIONS... 

Mainz, Germany, 4th-5th Nov.1997, p.87-115. 6124 NEW POLYETHYLENE AND POLYSTYRENE POLYMERS FOR FOAM APPLICATIONS Kelusky E C Nova Chemicals Ltd. 

Diverse foam structure applications In foam rubber, foamed polymers, shaving foams, milk shakes, and whipped creams, slowly draining thin liquid films (TLF) are needed. Accordingly, the rate of drainage is the most important factor in such industrial foam applications. 

The bulk of the ngid polyurethane and polyisocyanurate foam is used in insulation. See also Insulation (Thermal) More than half (60%) of the rigid foam consumed in 1994 was in the form of board or laminate die remainder was used in pour-in-place and spray foam applications. 

Direct application of dye liquor by spraying, foam application, or printing. 

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],... 

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