Cellular polystyrene, insulation material

In the mid-to-late 1980s, growth estimates of the use of polystyrene and polyurethane cellular plastic insulation materials and products were a healthy 10% per year and greater for phenolic (40,41). The principal application where strongest growth was forecast for these types was for roofing, especially single-membrane systems (42). 

Polystyrene is now available in certain forms in which the properties of the product are distinctly different from those of the parent polymer. Of these by far the most important is expanded polystyrene, an extremely valuable insulating material now available in densities as low as 1 Ib/ft (16kg/m ). A number of processes have been described in the literature for the manufacture of the cellular product of which four are of particular interest in the manufacture of large slabs. 

A variety of cellular plastics exists for use as thermal insulation as basic materials and products, or as thermal insulation systems in combination with other materials (see Foamed PLASTICS). Polystyrenes, polyisocyanurates (which include polyurethanes), and phenolics are most commonly available for general use, however, there is increasing use of other types including p olye thylene s, polyimides, melamines, and poly (vinyl chlorides) for specific applications. 

Molded articles from cellular polysulfone, coated with polystyrene, epoxy resin, or vinyl resin, are reported to have improved hardness and surface rigidity. They can also be used as insulating or packaging materials, or, when modified with urea-formaldehyde resin, as flowerpots that are permeable to air and water. These foams have excellent selfextinguishing and low anoke-generating properties (21). 

Thermal insulators comprise an equally broad range of materials. Such inorganics as mineral fibers, magnesia, aluminum silicate, cellulose, and glass fibers are widely used for steam and hot-water pipes, furnaces, and blown-in home insulation. Organic products that are effective include plastic foams (polyurethane, polyvinyl chloride, polystyrene) and cellular rubber. There are a number of materials that may be called double insulators, since they have both electrical and thermal insulating properties,... 

The use of cellular styrene plastics for insulation has been widespread for many years (25). More recently, polystyrene "structural" foams have been used, especially in wood replacement applications. Such use is expected to grow in the future, particularly as wood becomes less available and greater demands are placed on more efficient use of "short" plastic materials. 

Abstract The article is focused on the observation of usable possibilities of waste polystyrene that is created during foundry production and that could be used for production of cellular construction material. Thanks to its granulometry this kind of waste polystyrene is very suitable for use in the fine-soft Polymer-Modified Mortars (PMM), for example in the paste and gluing materials determined for ETICS (External Thermal Insulation Composite Systems). The mixtures for waste polystyrene application feature the required cellular light property, they conform to the requirements on the solidity and adhesiveness and conform also to the tension tests for the reinforcing layer. 

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