Plastics fluorocarbon

Suitable Plastics Fluorocarbons, chlorinated poly ether, polyvinylidene fluoride, polypropelene, high-density polyethylene, and epoxy glass. 

Use Plastics—fluorocarbons, polycarbonates, acrylics, ABS, polypropylenes, polyethylenes and nylons, with approval of site project coordinator. 

Testing and Standards. Requirements for extmsion and mol ding grades are cited in ASTM specifications (79) and in Federal specification LP-389A of May 1964 (80). For fabricated shapes, FEP film and sheet are covered by Aeronautical Material Specifications (AMS) 3647 and LP-523 (81). Besides the specifications covered by the Fluorocarbons Division of the Society of the Plastics Industry, Inc. (82), other specifications are Hsted in Reference 83. 

Plastics. Citric acid and bicarbonate are used as an effervescent blowing agent to foam polystyrene for insulated food and beverage containers replacing blowing agents such as chlorinated fluorocarbons (194—206). 

ABS plastic, a polymer consisting of polybutadiene spheroids is dispersed in a continuous phase of poly(styrene—acrylonitrile). The chromic acid attacks the polybutadiene at a much higher rate than the continuous phase. This gives an excellent microroughened surface with superior metal-to-plastic bond strength. A typical recommended formulation consists of 20 vol % sulfuric acid, 420 g/L chromic acid, and 0.1—1.0% of a fluorocarbon wetting agent. The plastic is treated with this formulation for 6—10 min at 60—65°C. 

Commonly accepted practice restricts the term to plastics that serve engineering purposes and can be processed and reprocessed by injection and extmsion methods. This excludes the so-called specialty plastics, eg, fluorocarbon polymers and infusible film products such as Kapton and Updex polyimide film, and thermosets including phenoHcs, epoxies, urea—formaldehydes, and sdicones, some of which have been termed engineering plastics by other authors (4) (see Elastol rs, synthetic-fluorocarbon elastol rs Eluorine compounds, organic-tdtrafluoroethylenecopolyt rs with ethylene Phenolic resins Epoxy resins Amino resins and plastics). 

Even though potential memory exists in all TPs, polyolefins, neoprenes, silicones, and other cross-linkable TPs are example of plastics that can be given memory either by radiation or by chemically curing. Fluorocarbons, however, need no such curing. When this phenomenon of memory is applied to fluorocarbons such as TFE, FEP, ETFE, ECTFE, CITE, and PVF2, interesting high-temperature or wear-resistant applications become possible. 

Elasticity If the product requires flexibility, examples of the choices includes polyethylene, vinyl, polypropylene, EVA, ionomer, urethane-polyester, fluorocarbon, silicone, polyurethane, plastisols, acetal, nylon, or some of the rigid plastics that have limited flexibility in thin sections. 

Between 250 and 450°F (121 and 232°C), plastics used include glass or mineral-filled phenolics, melamines, alkyds, silicones, nylons, polyphenylene oxides, polysulfones, polycarbonates, methylpentenes, fluorocarbons, polypropylenes, and diallyl phthalates. The addition of glass fillers to the thermoplastics can raise the useful temperature range as much as 100°F and at the same time shortens the molding cycle. 

Flame resistance The underwriters ruling on the use of self-extinguishing plastics for contact-carrying members and many other components introduces critical material selection problems. All TSs are basically self-extinguishing. Nylon, polyphenylene oxide, polysulfone, polycarbonate, vinyl, chlorinated polyether, chlorotrifluoroethy-lene, vinylidene fluoride, and fluorocarbon are examples of TPs that may be suitable for applications requiring self-extinguishing properties. Cellulose acetate and ABS are also available with these properties. Glass reinforcement improves these materials considerably. 

Moisture Deteriorating effects of moisture are well known as reviewed early in this chapter (OTHER BEHAVIOR, Drying Plastic). Examples for high moisture applications include polyphenylene oxide, polysulfone, acrylic, butyrate, diallyl phthalate, glass-bonded mica, mineral-filled phenolic, chlorotrifluoroethylene, vinylidene, chlorinated polyether chloride, vinylidene fluoride, and fluorocarbon. Diallyl phthalate, polysulfone, and polyphenylene oxide have performed well with moisture/steam on one side and air on the other (a troublesome... 

Chlorinated polyether is formulated particularly for products requiring, good chemical resistance. Other materials exhibiting good chemical resistance include all of the fluorocarbon plastics, ethylpentenes, polyolefins, certain phenolics, and diallyl phtha-late compounds. Additives such as fillers, plasticizers, stabilizers, colorants, and type catalysts can decrease the chemical resistance of unfilled plastics. Certain chemicals in cosmetics will affect plastics, and tests are necessary in most cases with new formulations. Temperature condition is also very important to include in the evaluation. Careful tests must be made under actual use conditions in final selection studies. 

Thermoplastics ABS, acetal and polyacetal, acrylic (methyl methacrylate), cellulose plastic, EVA, fluorocarbon, PTFE,... 

Entries on new materials, including re-cyclate plastics, fullerenes, hard-surfaced polymers, dendrimers, transflective materials, rapid prototyping materials, silicone nitride, supercritical fluids, bulk molding compounds, conversion coatings, folic acid, replacements for chloro-fluorocarbons ... 

Used to manufacture pesticides, shockproof plastics, acids, esters, ketones, flame retardants, fluorocarbons used as biocide. 

Used industrially as a chemical intermediate in organic synthesis. Produced by decomposition of fluorocarbon plastics when heated between 932 and 1202°F. 

Miscellaneous compounds. Other materials used include FC-171, fluorocarbon surfactant, 3M Industrial Chemical Products Division, St. Paul MN 55144-1000 Byk 306, Bykchemie USA, Wallingford, CT 06492 Polyol (poly-caprolactonetriol a polyester polyol), and Silwet L-7602 (polyalkylene oxide modified polydimethylsiloxane), both from Union Carbide Chemicals and Plastics Co., Inc., Danbury, CT 06817-0001. 

Several classes of polymers including epoxies have been developed from 2-phenyl-l,l,l,3,3,3-hexafluoropropan-2-ol and its derivatives.1 Fluorinated epoxy resins are the key intermediates for the new types ofpractical organic coatings and plastics, which have fluorocarbon properties and convenient characteristics such as hydrophobicity, oleophobicity, light stability, low friction, and, in some cases, possibly high thermal stability. 

The fluorocarbons are resistant to the action of strong acids and aqueous alkalis they are non-inflammable and attacked only by such reagents as fused caustic alkalis. The plastic teflon is polymerized C2F4 (cf. polythene which is polymerized C2H4) and is made into tubing, or into sheets to act as linings for vessels required to withstand corrosion. The liquid fluorocarbons ( fluorolubes ) are used where hydrocarbon oils would be attacked, and their non-inflammability makes them particularly useful. 

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