Poly phenylene

insoluble poly(phenylenes) with the monomeric unit - 5114- can be produced from benzene with AICI3/CUCI as catalyst. The polymer is branched, but not cross-linked to a network. The degree of polymerization, measured with the soluble sulfonate derivative, is 100. Stepwise-polymerized poly(l,4-phenylene) is not strongly colored. Consequently, the strong discoloration of poly(phenylenes) produced by polymerizing benzene must result from impurities or from bonding irregularities. 

The commercial synthesis of poly(phenylenes) starts with a mixture of 0-, m-, and p-terphenyl (subsequently referred to as Ar). The mixture is converted to chloroform-soluble prepolymers with m-benzene disulfonyl chloride. The arylation reaction consists of a thermal degradation reaction of the sulfonyl chloride in the presence of terphenyls. Presumably, this involves a free radical process, and not a Friedel-Crafts reaction  

The strong o- and m-substitution suggests a free radical mechanism. At low temperatures and with traces of iron as catalyst, sulfones are formed as side products. 

the prepolymer (as an immersion lacquer for laminates or when intended as a filler) is converted to an insoluble and infusible polymer with sulfuryl chloride (SO2CI2). Powdered poly(phenylenes) are compressed into isotactic molded components at 400°C and high pressure in a kind of sinter process. 

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The polymer described in the last problem is commercially called poly (phenylene oxide), which is not a proper name for a molecule with this structure. Propose a more correct name. Use the results of the last problem to criticize or defend the following proposition The experimental data for dimer polymerization can be understood if it is assumed that one molecule of water and one molecule of monomer may split out in the condensation step. Steps involving incorporation of the monomer itself (with only water split out) also occur. 

POLYTffiRSCONTAININGSULFUR - POLY(PHENYLENE SULFIDE)] (Vol 19) Fosamine-ammomum [25954-13-6]... 

Single layer OLEDs have been fabricated with a variety of emitter molecules and conjugated polymers such as poly(phenylene vinylene) (PPV). 

Physical or chemical vapor-phase mechanisms may be reasonably hypothesized in cases where a phosphoms flame retardant is found to be effective in a noncharring polymer, and especially where the flame retardant or phosphoms-containing breakdown products are capable of being vaporized at the temperature of the pyrolyzing surface. In the engineering of thermoplastic Noryl (General Electric), which consists of a blend of a charrable poly(phenylene oxide) and a poorly charrable polystyrene, experimental evidence indicates that effective flame retardants such as triphenyl phosphate act in the vapor phase to suppress the flammabiUty of the polystyrene pyrolysis products (36). 

PBO andPBZT. PBZ, a family of/ -phenylene-heterocycHc rigid-rod and extended chain polymers includes poly(/)-phenylene-2,6-benzobisthiazole) [69794-31-6] trans-V 27V) and poly(/)-phenylene-2,6-benzobisoxazole) [60871-72-9] (ot-PBO). PBZT and PBO were initially prepared at the Air Force Materials Laboratory at Wright-Patterson Air Force Base, Dayton, Ohio. PBZT was prepared by the reaction of... 

Because the chemical stmcture of poly(phenylene sulfide) [9016-75-5] (PPS) does not fall into any of the standard polymer classes, the Federal Trade Commission granted the fiber the new generic name of Sulfar. The fiber has excellent chemical and high temperature performance properties (see... 

In addition to carbon and glass fibers ia composites, aramid and polyimide fibers are also used ia conjunction with epoxy resias. Safety requirements by the U.S. Federal Aeronautics Administration (FAA) have led to the development of flame- and heat-resistant seals and stmctural components ia civiUan aircraft cabias. Wool blend fabrics containing aramids, poly(phenylene sulfide), EDF, and other inherently flame-resistant fibers and fabrics containing only these highly heat- and flame-resistant fibers are the types most frequently used ia these appHcations. 

AppHcation of an adhesion-promoting paint before metal spraying improves the coating. Color-coded paints, which indicate compatibiHty with specific plastics, can be appHed at 20 times the rate of grit blasting, typically at 0.025-mm dry film thickness. The main test and control method is cross-hatch adhesion. Among the most common plastics coated with such paints are polycarbonate, poly(phenylene ether), polystyrene, ABS, poly(vinyl chloride), polyethylene, polyester, and polyetherimide. 

The more familiar source-based names for these polymers are poly(phenylene oxide) (1), poly(ethylene terephthalate) (2), and polycaprolactam (3). 

Acrylic ESTER POLYMERS Acrylonitrile POLYMERS Cellulose esters). Engineering plastics (qv) such as acetal resins (qv), polyamides (qv), polycarbonate (qv), polyesters (qv), and poly(phenylene sulfide), and advanced materials such as Hquid crystal polymers, polysulfone, and polyetheretherketone are used in high performance appHcations they are processed at higher temperatures than their commodity counterparts (see Polymers containing sulfur). 

Polymer Blends. Commercial blends of nylon with other polymers have also been produced in order to obtain a balance of the properties of the two materials or to reduce moisture uptake. Blends of nylon-6,6 with poly(phenylene oxide) have been most successflil, but blends of nylon-6,6 and nylon-6 with polypropylene have also been introduced. 

One class of aromatic polyethers consists of polymers with only aromatic rings and ether linkages ia the backbone poly(phenylene oxide)s are examples and are the principal emphasis of this article. A second type contains a wide variety of other functional groups ia the backbone, ia addition to the aromatic units and ether linkages. Many of these polymers are covered ia other articles, based on the other fiinctionahty (see Polymers containing sulfur, POLYSULFONES). 

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