Plastic products windows

In the absence of such sources of NO, indoor and outdoor concentrations are quite similar (e.g., Weschler et al., 1994), since removal of NO and N02 indoors, e.g., on surfaces, is relatively slow. However, as discussed shortly, although the surface reaction of N02 is relatively slow, it is still of interest since it generates nitrous acid (HONO). Different surfaces found inside homes have been found to have different removal rates for N02. Figure 15.4, for example, shows measured rates of removal of N02 by a number of common household materials (Spicer et al., 1989). Large variations in removal rate (and hence the formation of products such as NO and HONO see later) are evident, varying from negligible for plastic storm windows to quite large for wallboard. 

Optical properties are of most relevance for plastics, although color and gloss can be important for any of the material classes for products where aesthetic considerations are of intere.st. In fact for most plastics products it is the aesthetic properties, such as surface texture, color, gloss, and reflectance, that are important. Light transmission characteristics and refractive index measurements are needed for only a relatively few products such as lenses and windows where the transparency or transluccncy of the material is a paramount consideration. This is unfortunate, as light transmission and refractive index are a good deal easier to define and and to correlate with visual experience than the other properties mentioned. Meeten [I] has edited a detailed text on the optical properties of polymers. 

Transparent (clear) engineering thermoplastics are used increasingly for medical, automotive, and architectural products windows, skylights, panels compact disks, fiber-optics sleeves lenses, reflectors, and light transmission pipes. ASTM D1003 (ISO 14782/13468), Haze and Luminous Transmittance of Transparent Plastics (Hazemeter or Spectrometer), describes optical properties of thermoplastics. 

Plastic products, technical products, heat transfer fluids, aviation fluids and pharmaceutical services in total represent some 13% of net sales with the remaining 7%, or so, coming from CPFilms, Solutia s branded aftermarket window films business. 

Polycarbonate - PC - is much easier to collect separately from other plastic products because it is used in well determined applications, like electric and electronic items, windows, etc. The recycling of PC can become, however, very difficult because of the presence of humidity. In this case, as for PET, dramatic degradation phenomena take place with consequent reduction of the properties of the recycled material. 

The amount of plasticizer added to the polymer in question varies, depending on the magnitude of the effect required. For example, a small addition of plasticizer may be made simply to improve the workabiUty of the polymer melt. This contrasts with larger additions made with the specific intention of completely transforming the properties of the product. For example, PVC without a plasticizer, ie, unplasticized PVC (PVC-U), is used in appHcations such as pipes and window profiles with plasticizer added, articles such as PVC food film, PVC cable insulation, and sheathing and PVC floorings are formed. 

Polystyrene. Polystyrene [9003-53-6] is a thermoplastic prepared by the polymerization of styrene, primarily the suspension or bulk processes. Polystyrene is a linear polymer that is atactic, amorphous, inert to acids and alkahes, but attacked by aromatic solvents and chlorinated hydrocarbons such as dry cleaning fluids. It is clear but yellows and crazes on outdoor exposure when attacked by uv light. It is britde and does not accept plasticizers, though mbber can be compounded with it to raise the impact strength, ie, high impact polystyrene (HIPS). Its principal use in building products is as a foamed plastic (see Eoamed plastics). The foams are used for interior trim, door and window frames, cabinetry, and, in the low density expanded form, for insulation (see Styrene plastics). 

Extrusion, by its nature, is ideally suited to the production of continuous lengths of plastic mouldings with a uniform cross-section. Therefore as well as producing the laces as described in the previous section, the simple operation of a die change can provide a wide range of profiled shapes such as pipes, sheets, rods, curtain track, edging strips, window frames, etc (see Fig. 4.18). 

In light of the many types of behavior plastics that can manifest and the considerable effect this behavior can have on the performance of the finished product, it behooves designers to become familiar with specific behavior characteristics of each plastic considered for an application. Recognize potential problems. A major cause for problems is not of poor product design but instead that the processes operated outside of their required operating window. This subject will be reviewed latter in this Chapter under PROCESS CONTROL... 

Materia] Selector Access to (1) GE Select, a comprehensive database in Microsoft Windows format of the family of GE polymers which allows users to sort for the GE product families and grades of materials that will best meet the specified property ranges, and (2) CAMPUS, a worldwide database for plastic materials with uniform global protocol for acquiring and comparing data on competitive plastic materials. 

Most UV photodiodes have a sealed metal TO package with an entrance window made of glass or special UV-transmitting glass. A TO housing is extremely reliable but it often counts for a non-negligible part of the sensor costs. Cheaper housings that should be favored for consumer-product applications like in household appliances are hard to find. Full-plastic encapsulation requires a UV-transpar-... 

Flexible PVC resins and other dioctylphthalate-containing plastics and resins are used in a variety of industrial and domestic products plastisols for carpetback coating (EPA 1987b), film, wire, cables, and adhesives (HSDB 1995). Additional end-use products are automobile and furniture upholstery, wall coverings, window shades, garden hoses, shower curtains, tablecloths, rainwear, shoes, dolls, and toys (Mannsville Chemical Products Corporation 1989). 

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