Foam sheets

FOAAffiD PLASTICS] (Vol 11) Extruded polystyrene foam sheet... 

Foamed polymers Foamed sheet Foamed silicone rubber Foam fractionation... 

Polyurethane. SmaU quantities of polyurethane film are produced as a tough mbber-like film. Polyurethane is more commonly used to produce foamed sheet, both flexible and rigid. The flexible foam is used as cushioning in furniture and bedding the rigid foam is widely used for architectural insulation because of its outstanding thermal insulation efficiency (see Urethane POLYMERS). 

Sheeting materials are utilized in a wide variety of appHcations (17). About 30% of the sheet market is foamed sheet, mostly all polystyrene, used for... 

Low deasity polyethyleae foam products (thin sheets, planks, rounds, tubes) ia the range of 32—160 kg/m (2—10 lbs/ft ) have beea prepared by an extmsion technique usiag various gaseous fluorocarboa blowiag ageats (100,101). The techniques are similar to those described earlier for produciag extmded polystyreae foam planks and foam sheets. 

The clean, durable, nondust-forrning character of polyethylene foam has led to its acceptance in packaging missile parts (230). Polyethylene foam sheet has also displaced polystyrene foam sheet for packaging glass bottles and containers because of its greater resUiency and tear resistance. 

Property Styrofoam/ extmded Bead, board-molded Foam sheet ASTM... 

Eamination ofTrycite Plastic Films to Polystyrene Foam Sheet, Bulletin No. 500-898-79, The Dow Chemical Co., Midland, Mich., 1979. 

Vinylidene Chloride Copolymer Foams. Low density, fine-celled VDC copolymer foams can be made by extmsion of a mixture of vinylidene chloride copolymer and a blowing agent at 120—150°C (190). The formulation must contain heat stabilizers, and the extmsion equipment must be made of noncatalytic metals to prevent accelerated decomposition of the polymer. The low melt viscosity of the VDC copolymer formulation limits the size of the foam sheet that can be extmded. 

Product Hterature on KURASHEET activated carbon foam sheets, Kuraray Chemical Co., Ltd., Japan, 1987. 

POLYURETHANE FOAM SHEETS OR BLOCKS. These are required to resist ignition source 5 (17 gram wood crib) of BS5852 Part 2 except that the flames may penetrate the full depth of the specimen and that the mass loss (due to burning and liquid residues falling from the test rig) shall not exceed 60 grams. 

Foamed boards, 23 403—404 Foamed polystyrene, 23 403 Foamed sheet polystyrene, 23 408 Foamex, commercial defoamer, 3 24 It Foam extrusion, 19 549 Foam-forming materials, injection of, 12 22-23... 

At atmospheric pressure the foam structure depends on the formulation and processing parameters. Foamed sheets and imitation leathers can be manufactured by this process. 

Figure 10.8 Schematic of screw cooling at a viscoseal for a tandem foam sheet line...

This chapter will present the three most common uses for melt-fed extruders (1) pumping of resin from a compounding operation to a pelletizer, (2) large-diameter extruders used for finishing sections in resin production plants, and (3) secondary cooling extruders for foam sheet lines. 

Secondary Extruders for Tandem Foam Sheet Lines... 

Volume changes due to diffusion of butene from, and air into, a 5 mm thick foam sheet of density 28 kg m, with... 

The small cell size only has limited effects on properties, but can have advantages for further processing. If foamed sheet is to be thermoformed, it must have a cell diameter much less than the sheet thickness to avoid failure. 

Low density PE foam sheets having a thickness of 10 mm were cut from a block produced by compression moulding and their thermal conductivities over the temperature range from 24 to 50C determined. The evolution of the properties along the block was analysed and the cell structure, apparent mean cell diameter, anisotropy, mean cell wall thickness and relative fraction of polymer determined using quantitative image analysis and a previously reported model utilised to predict the thermal conductivity of the foams. 30 refs. 

Houston, Tx., 25th-28th Eeb. 2001, p.431-40 MUCELLTHERMOFORMABLE POLYOLEFIN FOAM SHEET Blizard K Chapman B Trexel Inc. 

A textured metallocene polyethylene foam sheet suitable for use in a floor covering is made using a highly coactivated azodicarbonamide package which blows the metallocene polyethylene effectively. The preferred coactivators are zinc oxide and urea. The textured surface of metallocene polyethylene foam is formed by a chemical embossing process which utilises a liquid triazole having an alkyl moiety as a foam-expansion inhibitor. The triazole is dissolved in a non-polar solvent to form the foam inhibitor. The preferred inhibitor is a hydrocarbon which may be halogenated. 

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