Polyvinylidene chloride plastic

PVC, polythene and PTFE if moist gas is used Stainless steel, copper, nickel. Monel, brass, aluminium for dry gas <200°C. Borosilicate glass for low pressures. For moist gas, copper and polyvinylidene chloride plastics Monel and nickel Monel and nickel Most common metals so long as gas is dry... 

Saran Dow chemicafs trade name for its polyvinylidene chloride plastic. 

SAN (styrene acrylonitrile) Polyvinyl chloride Plasticized Unplasticized Polyvinylidene chloride Styrene copolymer (SMA) Crystal Impact... 

MIR techniques have simplified obtaining infrared spectra of many materials important in packaging. These include rubber, plastics, laminations, and components of these materials that find use in pumps, sample packages, and devices. The combination of MIR and computerized pattern recognition techniques can be used for differentiating and classification of flexible packaging polymers such as polyvinyl chloride (PVC), polyvinylidene chloride (PVdC), acrylonitrile (Barex), and CTFE (Aclar) [22]. 

Another important addition polymer is polyvinylchloride (PVC), which is tough and easily molded. Floor tiles, shower curtains, and pipes are most often made of PVC, shown in Figure 12.30. The addition polymer polyvinylidene chloride (trade name Saran), shown in Figure 12.31, is used as plastic wrap for food. The large chlorine atoms in this polymer help it stick to surfaces such as glass by dipole—induced dipole attractions, as we saw in Section 7.1. 

In spite of Baekeland s success, it was another two decades before the Age of Polymers can really be said to have been born. The 1920s and 1930s saw the invention and/or commercialization of a number of new polymeric products ("plastics") that most consumers now consider to he essential chemicals in their lives. These products include the urea formaldehyde plastics (1923), polyvinyl chloride (PVC 1926), polystyrene (1929), nylon (1930), polymethylmethacrylate (acrylics 1931), polyethylene (1933), the melamine plastics (1933), polyvinylidene chloride (Saran 1933), polyvinyl acetate (PVA 1937), and tetrafluoroethylene (Teflon 1938). 

Polyvinylchloride, polyvinylidene chloride, polyvinyl fluoride Trichloroethylene, methyl ethyl ketone 1. Abrasion grit or vapor blast or 100-grit emery cloth followed by solvent degreasing. 2. Solvent wipe with ketone. Suitable for rigid plastic. For maximum strength, prime with nitrile phenolic adhesive Suitable for plasticized material... 

Barrier Plastics. When plastics replace metals and glass in packaging, their permeability is often a limiting property. Barrier performance generally increases with density and crystallinity. The most promising barrier plastics include ethylene/vinyl alcohol, polyvinylidene chloride, polyacrylonitrile, and polyethylene naphthoate. These are used most efficiently by laminating them to commodity plastics such as polyethylene and polyethylene terephthalate. 

Vinyls are one of the most versatile families of plastics. The term vinyl usually identifies the major very large production of polyvinyl chloride (PVC) plastics. The vinyl family, in addition to PVCs, consists of polyvinyl acetals, polyvinyl acetates, polyvinyl alcohols, polyvinyl carbazoles, polyvinyl chloride-acetates, and polyvinylidene chlorides. As a family, they are strong and abrasion resistant. They are unaffected, for the most part, by prolonged exposure to water, common chemicals,... 

BMs commonly include from two to seven layers, although more are also used. The construction usually includes one or more barrier layers. These are plastics with a particular resistance to the transmission of water vapor or gases such as oxygen or carbon dioxide. Examples are ethylene vinyl alcohol (EVOH), nylons, and polyvinylidene chloride (PVDC). Their presence greatly enhances the performance of the BM as a package for foodstuffs, beverages, and other critical products. The barrier materials are all deficient in some respect such as price, mechanical strength, and moisture resistance. Thus not used as a material of sole construction for BM. Their use is in thin layers shielded by other more robust and economical body plastics. 

Any post-consumer plastic stream will contain some halogens in the form of polyvinyl chloride, polyvinylidene chloride, brominated flame retardants, halogenated additives, food waste, or salt. Therefore, two issues must be considered. First, the gas stream resulting from the depolymerization of plastics must be scrubbed to remove any halogenated gases to satisfy emissions controls. Second, halogens in the liquid product must be minimized to increase its value and marketability. Therefore the Conrad process has been developed. It is a robust process unit that can accommodate a variable feedstream and produce a consistent product, free of nonhydrocarbon impurities by low feed preparation costs. 

All rubbers, glasses, and plastics are polymers. You are probably familiar with natural polymers like cellulose (the building block of plant fibers) and synthetic polymers like polyethylene (plastic milk cartons), polyisoprene (automobile tires), polyethylene terephthalate (soft drink bottles), polymethyl methacrylate (Plexiglas ), polyvinylidene chloride (transparent plastic wrap), polytetrafluoroethylene (Teflon ), and various polyesters (fabrics). Polyvinyl chloride, the polymer shown earlier, is used to make rigid pipes, house siding, and protective coverings for automobile seals and dashboards, among many other applications. 

Polyvinylidene chloride is primarily extruded as a film that has low permeability to water vapor and air and is therefore used as the familiar clinging plastic food wrap, Saran Wrap. 

The permeation for gases N2, 02, C02 is usually of the order of 1 4 20. Plastics with low permeabilities include polyvinylidene chloride, polyvinyl chloride, ethylene vinyl alcohol (if dry), nylon and PET. 

The use of other plastics tends to be related to specialised needs and whether their advantages justify the additional cost, e.g. Aclar (trade name) may cost twenty times more than PET but is the nearest approach to an inert plastic and is approximately ten times less permeable than Saran (PVdC—polyvinylidene chloride) which is widely used as a film coating. However foil, even when thin (0.006 mm and above) remains the best barrier material, with newer techniques of film metallisation, especially where two contact layers are used, coming a close second best. 

Polyvinylchloride (PVC) is commercially the most signihcant member of the family of vinyl resins. The other important members of this group are chlorinated-PVC (CPVC) and polyvinylidene chloride (PVDC). PVC is one of the most widely used, commodity type thermoplastics with an annual consumption of over 5 Mton/y in the USA. The excellent versatility of PVC is attributed to its blending capability with a variety of plasticizers, additives and fillers to yield products ranging from very flexible to very rigid types. In addition, PVC has a low cost advantage and a reasonably good balance of properties, which... 

Green edge Hydrochloric acid Chlorinated mbber Polyvinyl chloride Polyvinylidene chloride (without flammable plasticizers)... 

Flexible metal hose of bronze or stainless steel should be used for connecting a tank car or tank truck to the main unloading line. This will prevent breaking or bending of stationary pipe as the springs raise the tank car or truck during unloading. (Most trucks have or can have their own hoses.) A flexible hose lined with polyvinyl alcohol resin, polyvinylidene chloride, or polytetrachloroethylene plastic is also suitable for such use. The polyvinyl alcohol, however, must be protected from moisture, which readily attacks it. 

General Description Polyvinylidene Chloride (PVDC) resin is a copolymer of vinylidene chloride (VDC) with vinyl chloride or other monomers Dow Plastics vinyl chloride and vinylidene chloride, Saran, is usually supplied as a white, free-flowing powder. Dow Saran polymers are known worldwide for their gas-moisture, and chemical-barrier properties, and for their ignition-resistant properties. 

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