Poly , PIPE

Vinyl chloride is an industrial chemical produced in large amounts (10 ° Ib/year in the United States) and is used in the preparation of poly(vmyl chloride) Poly(vinyl chio ride) often called simply vinyl has many applications including siding for houses wall coverings and PVC piping... 

Poly(vinyl chloride) (PVC) has re placed leather in many of its appli cations PVC tubes and pipes are often used in place of copper... 

CeUular polymers are also used for pipe and vessel insulation. Spray and pour-in-place techniques of appHcation are particularly suitable, and polyurethane and epoxy foams are widely used. Ease of appHcation, fire properties, and low thermal conductivity have been responsible for the acceptance of ceUular mbber and ceUular poly(vinyl chloride) as insulation for smaller pipes. 

The newer open-ceU foams, based on polyimides (qv), polyben2imida2oles, polypyrones, polyureas, polyphenylquinoxalines, and phenoHc resins (qv), produce less smoke, are more fire resistant and can be used at higher temperatures. These materials are more expensive and used only for special appHcations including aircraft and marine vessels. Rigid poly(vinyl chloride) (PVC) foams are available in small quantities mainly for use in composite panels and piping appHcations (see Elame retardants Heat-RESISTANTPOLYA rs). 

Heat-reactive resins are more compatible than oil-soluble resins with other polar-coating resins, such as amino, epoxy, and poly(vinyl butyral). They are used in interior-can and dmm linings, metal primers, and pipe coatings. The coatings have excellent resistance to solvents, acids, and salts. They can be used over a wide range of temperatures, up to 370°C for short periods of dry heat, and continuously at 150°C. Strong alkaUes should be avoided. 

Recommended materials of constmction for pipes, tanks, and pumps handling citric acid solutions are 316 stainless steel, fiber glass-reinforced-polyester, polyethylene, polypropylene, and poly(vinyl chloride). At elevated temperatures, 304 stainless steel is not recommended (Table 8). 

Industrial equipment is a continuing area of development for plastics. Pipes, pumps, valves and sight glasses, made from such materials as PVC, PTFE and poly-4-methylpent-l-ene, have become well established on account of their corrosion resistance. The nylons are used for such diverse applications as mine conveyor belts and main drive gears for knitting machines and paper-making equipment. These and other materials are widely used where such features as toughness, abrasion resistance, corrosion resistance, non-stick properties, electrical insulation capability and transparency are of importance. 

In the massive form poly(vinyl chloride) is a colourless rigid material with limited heat stability and with a tendency to adhere to metallic surfaces when heated. For these, and other, reasons it is necessary to compound the polymer with other ingredients to make useful plastics materials. By such means it is possible to produce a wide range of products, including rigid piping and soft elastic cellular materials. 

Recent trends in protective coatings used on buried pipelines have been away from reinforced hot applied coal tar and asphalt enamels and butyl rubber laminate tapes, particularly where applied over-the-ditch . The more recently developed coatings based on fusion bonded epoxies, extruded poly-ethylenes, liquid-applied epoxies and polyurethanes, require factory application where superior levels of pipe preparation and quality control of the application process can be achieved. 

HMPB 4-Hydroxymethyl-3-methoxyphenoxybutyric acid MAOS Microwave-assisted organic synthesis NBS AT-Bromosuccinimide NIS AT-Iodosuccinimide PIPE Poly(tetrafluroethylene)... 

The quantity of these materials is relatively small compared with the amount of waste high-density poly(ethylene) produced each year. Containers made from HDPE are widely used for detergents, oil, and antifreeze, and enormous amounts of material are used in disposable applications aimually. In principle recycled poly(ethylene) could be used for drain pipes, flower pots, dustbins, and plastic crates. The problem remains, however, that economics do not favour recycling of these polymers and in the absence of Government intervention little or nothing can be done to alter commercial attitudes towards recycling. 

About 10% of the ethylene produced in the U.S. is used to make vinyl chloride, which in the chemical trade is usually referred to as vinyl chloride monomer or VCM. The largest use of VCM is for polymerization to poly(vinyl chloride) (PVC), a thermoplastic, which in terms of volume is second only to polyethylene. PVC is used in such diverse areas as containers, floor coverings (linoleum), plastic pipes, raincoats, and many, many others. PVC has an evironmental disadvantage over non-chlorine containing plastics in that when it is disposed of by incineration it produces hydrogen chloride, which dissolves in atmospheric water to give hydrochloric acid. Polyethylene does not have this undesirable feature. 

In Japan the amount of waste poly(vinyl chloride) (PVC) has been sharply increasing since disposal of building materials such as pipe and roof liners with long service life has been started recently. It was estimated to be approximately one million tons in FY 2000, and it is predicted to increase further to approximately 1.8 million tons in FY 2020. Since the landfill sites run short and the incineration to reduce its volume produces dioxins and corrodes boiler tube by hydrogen chloride, development of a safe and inexpensive technology for the recycling of waste PVC is one of the most urgent issues. 

The United States produces more than 7 billion kilograms of vinyl chloride annually. Most is converted to the polymer poly(vinyl chloride) (PVC), which is used to make piping, siding, gutters, floor tiles, clothing, and toys. Vinyl chloride is made in a two-step process. The balanced overall equation is as follows ... 

Poly(propene) Ropes, carpets, clothing, pipes, crates... 

Poly(l,4-benzamide) (PBA), 13 371 Poly(1-butene) (PB), 4 429. See also Blown PB film Isotactic PB resins Isotactic poly(l- butene) (PB) PB entries Pipe-grade PB resin Syndiotactic poly(1-butene) (PB) mechanical properties of, 20 418 polymerization processes for, 20 424-425 uses of, 20 430-431 commercial manufacture of, 20 429 Poly-1-olefins, regioregular, 26 513 Poly(l,4-butylene terephthalate) (PBT), 10 188... 

Soundproofing and thermal insulation of missiles, planes and helicopters cryogenic protection on satellites, piping insulation, protection for embarked equipment in poly-imide foams. 

ISO 105-X10 Textiles - Tests for colour fastness - Part XIO Assessment of migration of textile colours into polyvinyl chloride coatings ISO 264 1976 Unplasticized polyvinyl chloride (PVC) fittings with plain sockets for pipes under pressure - Laying lengths - Metric series ISO 265-1 1988 Pipes and fittings of plastics materials - Fittings for domestic and industrial waste pipes - Basic dimensions Metric series - Part 1 Unplasticized poly(vinyl chloride) (PVC-U)... 

ISO 580 1990 Injection-moulded unplasticized poly(vinyl chloride) (PVC-U) fittings -Oven test - Test method and basic specifications ISO 727-1 2002 Fittings made from unplasticized poly(vinyl chloride) (PVC-U), chlorinated poly (vinyl chloride) (PVC-C) or acrylonitrile/butadiene/styrene (ABS) with plain sockets for pipes under pressure - Part 1 Metric series ISO 727-2 2002 Fittings made from unplasticized poly(vinyl chloride) (PVC-U), chlorinated poly (vinyl chloride) (PVC-C) or acrylonitrile/butadiene/styrene (ABS) with plain sockets for pipes under pressure - Part 2 Inch-based series ISO 1163-1 1995 Plastics - Unplasticized poly(vinyl chloride) (PVC-U) moulding and extrusion materials - Part 1 Designation system and basis for specifications ISO 1163-2 1995 Plastics - Unplasticized poly(vinyl chloride) (PVC-U) moulding and extrusion materials - Part 2 Preparation of test specimens and determination of properties ISO 1265 1979 Plastics - Polyvinyl chloride resins - Determination of number of impurities and foreign particles... 

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