Expandable polystyrene foam applications

In another application expanded polystyrene foam panels, 1.2 x 2.4 m, are faced with a wire mesh and mounted in a metal channel bolted to a concrete slab. These panels are then sprayed on both sides with plaster, which is anchored to the wire mesh and forms the interior and exterior surfaces. Roof and interior partitions provide low cost housing for mild climates. 

Because expanded polystyrene foam is processed at a lower temperature, aliphatic bromine compounds such as hexabromocyclododerane (HBCD) can be used for this application. The flame retardant levels in these systems are family low, typically less than 3wt%. These levels are sufficient to pass the Steiner Tunnel test, and synergists such as antimony trioxide are not necessary. 

Flame-retardant styrenic polymers find utility in applications such as building insulation (expanded polystyrene foam) and electronic enclosures (flame-retardant HIPS, ABS and styrenic blends). The most effective flame retardants are halogen-(particularly bromine)-containing compounds these flame retardants act by inhibiting the radical combustion reactions occurring in the vapor phase. Flame-retardant plastics are in a state of flux, due to influences of... 

Expanded polystyrene foam (EPS) has different applications, because of its physical form (beads) and properties (higher permeability to water and less effective adhesion to facing materials than polyurethane). The expansion gases, pentane and steam, escape fairly rapidly from the foam, so the thermal conductivity of the foam filled with air is about twice that of the best polyurethane foam—a 50 mm thick slab of foam has a U-value of 0.5-0.6 Wm K . EPS mouldings can be used as shutters (formwork) for pouring concrete in a composite wall. The two EPS layers are connected at intervals to fix the thickness of the concrete. Extruded polystyrene foam (XPS) is used in plank form for insulation imder the concrete floor of houses, and in roofing panels. 

Expanded polystyrene foam is used for thermal insulation and as a packaging material. It is often used for food trays. Polystyrene can also be crosslinked. Cross-linked polystyrene parts are often used in low-loss electrical and electronic applications requiring moderate resistance to temperature. 

Kaiman P, Biernacki JJ, Visco DP Jr. A review of physical and kinetic models of thermal degradation of expanded polystyrene foam and their application to the foam casting process. J Anal Appl Pyrolysis 2007 78 162. 

The foams, marketed by Rohm as Rohacell, are stable at room temperature to hydrocarbons, ketones, chlorinated solvents and 10% sulphuric acid. They may be used under load at temperature up to 160°C. Uses quoted for these materials include bus engine covers, aircraft landing gear doors, radar domes, domes, ski cores and tennis racket cores. Their potential is in applications demanding a level of heat deformation resistance, solvent resistance and stiffness not exhibited by more well-known cellular polymers such as expanded polystyrene and the polyurethane foams. 

Foamed polystyrene - which is also known as expanded polystyrene - is used extensively in a variety of applications, ranging from packaging peanuts to insulation board and single-use cups and plates. We produce it by two processes foam extrusion and bead expansion. Both types of expanded polystyrene consist of closed cells, i.e., bubbles with continuous walls. We can visually distinguish the two types of foam by the fact that products made by the expanded bead process consist of discrete beads that are welded together... 

It was possible to cover additional applications with these new types. In 1951 BASF found it was possible to impregnate polystyrene direct with expanding agents in the suspension process. This opened up great new possibilities for polystyrene foam (STYR0P0R, BASF, 33), for example in the packaging and building fields. 

While unaffected by water, styrofoam is dissolved by many organic solvents and is unsuitable for high-temperature applications because its heat-distortion temperature is around 77°C. Molded styrofoam objects are produced commercially from expandable polystyrene beads, but this process does not appear attractive for laboratory applications because polyurethane foams are much easier to foam in place. However, extruded polystyrene foam is available in slabs and boards which may be sawed, carved, or sanded into desired shapes and may be cemented. It is generally undesirable to join expanded polystyrene parts with cements that contain solvents which will dissolve the plastic and thus cause collapse of the cellular structure. This excludes from use a large number of cements which contain volatile aromatic hydrocarbons, ketones, or esters. Some suitable cements are room-temperature-vulcanizing silicone rubber (see below) and solvent-free epoxy cements. When a strong bond is not necessary, polyvinyl-acetate emulsion (Elmer s Glue-All) will work. 

The production and application in 1967 of 193 million pounds of polystyrene foam reflects considerable scientific, engineering, and commercial activity. The continuing growth of expandable polystyrene in this field is attributed to its ability to be steam molded economically into a variety of useful items. 

Applications. Polybutene sulfone foam can be used in all usual applications of rigid foams, in particular with the following obvious advantages over expanded polystyrene ... 

Major applications for styrene plastics are summarized in Table III (23). The packaging and serviceware (disposables) markets predominate, and account for approximately 50% of the total. One of the most rapidly growing portions of these markets is in low-density (usually 1-10 Ib/ft ) polystyrene foams, either in the form of extruded foam sheet or expanded polystyrene beads (EPS). Projections indicate that production of these foams will be greater than 2000 metric tons (24). 

Polystyrene can be made into a veiy-low-density foam which has found use in electrical, sound, and heat-insulation applications. The inflammability is a definite setback for such applications, and experiments are under way to use halogenated polystyrene for such purposes or to incoiporate ifiert and fire-resistant or fire-retarding ingredients. Polystyrene foam can also be produced from expandable beads which contain an expansion... 

Expanded polystyrene products have widely increased the market for polystyrene resin (see the section on polystyrene foams in Chapter 2). With as light a weight as 2 Ib/ft (0.032 g/cm ), the thermal conductivity of expanded polystyrene is very low, and its cushioning value is high. It is an ideal insulation and packaging material. Common applications include ice buckets, water coolers, wall panels, and general thermal insulation applications. 

Foams are available as rigid sheets or slabs (which are used in the majority of roofing systems), as beads and granules (used in cavity wall insulation), and also as spray and pour-in applications. The market is dominated by polyurethane (PU) foams, in particular polyisocyanurate products, expanded polystyrene (PS), and extruded polystyrene. 

Polystyrene foam (PS) holds much of the sheathing market. In masonry and brick walls, PS foams are mainly used because of their better moisture resistance. In cavity walls, loose fill PS is used, while exterior wall applications, which have no limitation on space, use low-cost expanded PS. 

Arco Chemical s line of Arpro expanded PP and Arpak expanded PE bead resins are used for the interior components. Polyolefin foams provide a higher degree of chemical resistance, heat resistance, and cushioning as compared to foamed polystyrene. Potential applications include seat backs, head rests, and other critical energy-absorbing areas. 

Poly (styrene-co-acrylonitrile). See Styrene/acrylonitrile copolymer Poly (styrene-co-allyl alcohol). See Styrene/allyl alcohol copolymer Poly (styrene-co-butadiene). See Styrene/butadiene polymer Poly (styrene-co-divinylbenzene). See Styrene/DVB copolymer Poly (styrene-co-maleic anhydride). See Styrene/MA copolymer Poly (styrene-co-methyl methacrylate). See Styrene/methyl methacrylate copolymer Poly (styrene-co-a-methylstyrene). See Styrene/a-methyl styrene resin Poly (styrene-divinylbenzene). See Styrene/DVB copolymer Polystyrene, expandable Synonyms EPS Expandable polystyrene Expanded polystyrene XPS Definition Amorphous PS beads contg. pentane as a blowing agent and coated with a lubricant the polymer is converted to foamed articles with a closed cell structure by applic. of steam Properties Beads (0.4-1.5 mm diam.)... 

PURAC has been producing pharmaceutical-grade lactic acid based polymers for medical applications during the last 30 years. These medical applications (e.g., sutures, bone screws) are not the focus of this chapter, which covers only the large-scale industrial applications of PLA. In 2008, PURAC started a d-LA program and produced L-lactide and D-lactide for its PLA partners, such as Synbra. Synbra plans to introduce small volumes of expandable PLA (BioFoam ) to extend its range of expanded polystyrene (PS)-based foam products, before building a 50,000 ton per year expanded-PLA production facility (Schut 2008). 

Flame-retardance of expanded polystyrene beads can be brought about by the application of the additive (e.g. pentabromophenyl allyl ether), dispersed in fine quartz flour, to the surface of beads before expansion. For the flame-retardance of extruded foam sheets, the agent should be admixed with the polystyrene granules. 

Both polyethylene and polystyrene are used extensively as thermoplastic foam materials in packaging as well as in building applications. Expandable polystyrene... 

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