Engineering plastics polyphenylene oxide

As in case of mixed cresols, mixed xylenols have been used for manufacture of carbolic soaps, disinfectants, wire enamels, and fire-retardant plasticizers. However, 2,4-xylenol, 2,6-xylenol, and 3,5-xylenols have been used for organic chemical synthesis. 2,6-Xylenol is a precursor for an engineering plastic polyphenylene oxide also known as polyphenylene ether. 

Polyphenylene oxide modified Very fough engineering plastic, superior dimensional stability, low moisture absorption, excellent chemical resistance Injection molding... 

Nylon, polyacetal, polycarbonates, poly(2,6-dimethyl)phenylene oxide (PPO), polyimides, polyphenylene sulfide (PPS), polyphenylene sulfones, polyaryl sulfones, polyalkylene phthalates, and polyarylether ketones (PEEK) are stiff high-melting polymers which are classified as engineering plastics. The formulas for the repeating units of some of these engineering plastics are shown in Figure 1.15. 

Several flexible polymers, such as natural rubber (NR) synthetic rubber (SR) polyalkyl acrylates copolymers of acrylonitrile, butadiene, and styrene, (ABS) and polyvinyl alkyl ethers, have been used to improve the impact resistance of PS and PVC. PS and copolymers of ethylene and propylene have been used to increase the ductility of polyphenylene oxide (PPO) and nylon 66, respectively. The mechanical properties of several other engineering plastics have been improved by blending them with thermoplastics. 

Engineering plastics are most frequently thought of as the acetals, nylons, fluorocarbons, phenolics, polycarbonate, and polyphenylene oxide, to name just a few. These are indeed engineering materials and for such applications are usually used in relatively small... 

Mixed esters, such as isopropylphenyl diphenyl phosphate and tcrt-butylphenyl diphenyl phosphate, are also widely used as both plasticizers/flame retardants for engineering thermoplastics and hydraulic fluids.11 These esters generally show slightly less flame-retardant efficacy, when compared to triaryl counterparts however, they have the added advantage of lower smoke production when burned. Some novel oligomeric phosphate flame retardants (based on tetraphenyl resorcinol diphosphate) are also employed to flame retard polyphenylene oxide blends, thermoplastic polyesters, polyamides, vinyls, and polycarbonates. 

Boric oxide is reported to be an effective fire retardant in engineering plastics such as polyphenylene ether (PPE)/high impact polystyrene (HIPS), polyetherketone, and polyetherimide.34-35 It is particularly effective when used in conjunction with PTFE or polyvinylidene fluoride. The use of boric oxide in conjunction with red phosphorus was reported to be an effective combination in fiberglass reinforced polyamide 6,6.36... 

To the range of engineering plastics were added polyethylene and polybutylene tereph-thalates (PET and PBT), as well as General Electric s polyethers, the PPO (polyphenylene oxide) produced through polymerization of 2,6-xylenol and the Noryl plastic produced by blending PPO with polystyrene. Other special polymers, derived like the polycarbonates from bisphenol A, were added to this range polyarylates, polysul-fones, polyetherimides. 

Fortunately, the deficiencies of both the classic thermosets and general purpose thermoplastics have been overcome by the commercialization of a series of engineering plastics including polyacetals, polyamides, polycarbonate, polyphenylene oxide, polyaryl esters, polyaryl sulfones, polyphenylene sulfide, polyether ether ketones and polylmides. Many improvements in performance and processing of these new polymers may be anticipated through copolymerization, blending and the use of reinforcements. 

Spin relaxation in dilute solution has been employed to characterize local chain motion in several polymers with aromatic backbone units. The two general types examined so far are polyphenylene oxides (1-2) and aromatic polycarbonates (3-5) and these two types are the most common high impact resistant engineering plastics. The polymer considered in this report is an aromatic polyformal (see Figure 1) where the aromatic unit is identical to that of one of the polycarbonates. This polymer has a similar dynamic mechanical spectrum to the impact resistant polycarbonates (6 ) and is therefore an interesting system for comparison of chain dynamics. 

Noryl . [GE Plastics GE Plastics Ltd.] Modified polyphenylene oxide resins engineering resin for inj. mcdding, ex> trasitm, structural foam used for computers, business equip., automotive, elec., electronics, construction, telecommunications, tqppliances, and other industries. 

Polyacetal polyphenylene oxide are widely used as engineering thermoplastics, and epoxy resins are used in adhesive and casting application. The main uses of poly(ethylene oxide) and poly(propylene oxide) are as macroglycols in the production of polyurethanes. Polysulfone is one of the high-temperature-resistant engineering plastics. 

Uses Disinfectant solvent for wire enamels pharmaceuticals insecticides fungicides herbicides plasticizers mbber chemicals paints additives to lubricants and gasoline mfg. of polyphenylene oxide wetting agents dyestuff synthetic resin comonomer for alkali-resist, phenolic resins froth flotation agent engine cleaner ingred. 

Norpex, PPO-based engineering thermoplastics. Custom Resins Group Norsfl, Two-component siUcones, Insulcast Noryl, Polyphenylene oxide-based resin, GE Plastics... 

Polyphenylene oxide (Noryl from GE) and polyphenylene sulfide (Ryton from Phillips) are used as high-temperature engineering plastics. Polyphenyl ether sulfones are manufactured by a number of companies under a variety of trade names including 720P, 220P by ICI and RADEL by Union Carbide. They are generally used as injection-moldable thermoplastics and in the adhesive and composite industry. 

In the light of these requirements, and in the interests of increasing production rates and reducing costs, the move away from phenolic and alkyd thermosetting plastics has seen the selection by connector designers of a number of engineering thermoplastics. Materials currently in use include polycarbonate, modified polyphenylene oxide (PPO), polybutylene terephthalate (PBT) and polysulphones. 

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