Polyarylene ether properties

This research was an attempt to develop new polymers with the mechanical properties of polyarylene ethers and the dielectric properties of fluoropolymers. After initially testing the viability of the [2n+ 2n] cyclodimerization reaction for preparing high-molecular-weight polymers and testing the dielectric properties of these polymers, two polymers (one thermoplastic and one thermoset) were prepared in larger quantities to evaluate the thermal and mechanical performance of these novel compositions. The high Te thermoset was also quantitatively tested for thermal/oxidative stability. 

Sulfonation is very useful chemical modification of polymer, as it induces high polarity in the polymer changing its chemical as well as physical properties. Sulfonated polymers are also important precursors for ionomer formation [75]. There are reports of sulfonation of ethylene-propylene diene terpolymer (EPDM) [76, 77], polyarylene-ether-sulfone [78], polyaromatic ether ketone [79], polyether ether ketone (PEEK) [80], styrene-ethylene-butylene-styrene block copolymer, (SEBS) [81]. Poly [bis(3-methyl phenoxy) phosphozene] [82], Sulfonated polymers show a distinct peak at 1176 cm"1 due to stretching vibration of 0=S=0 in the -S03H group. Another peak appears at 881 cm 1 due to stretching vibration of S-OH bond. However, the position of different vibrational bands due to sulfonation depends on the nature of the cations as well as types of solvents [75, 76]. 

EP 323142 (European) 1989 Ternary polyether ketone blend wire insulations Pirelli General PLC, UK CK Alesbury, RJ Murphy Formulation shows excellent stress craze resistance, flexibility and flame resistance Blends of polyarylene ether ketones, polyether imides and polyfimide siloxanes) were coated onto wire for solvent resistance, O index and abrasion resistance. Blends without siloxane-imide copolymer did not meet these properties... 

Reactive flexibilizers such as polysulfldes, urethanes, polybutadienes, and polyesters are copolymerized with epoxies to increase flexibihty, improve adhesion, modify electrical properties, and improve resistance to chemicals. Nonreactive extenders such as thermoplastics, asphaltums, and waxes are used to modify properties and reduce the cost of the compounds. Polyarylene ether sulfone as an extender in epoxy resins increases the fracture toughness fivefold with only a slight drop in Tg. 

R. N. Johnson, A. G. Farnham, R. A. Clendinning, W. F. Hale, and C. N. Merriam. "Poly(aryl Ethers) by nucleophilic aromatic substitution. I. synthesis and properties." Journal of Polymer Science PART A-1, pp. 2375-2398,1967. Robert N. Johnson and Alford G. Farnham. Polyarylene ethers. US Patent 4108837. August 22,1978. 

Of all the hydrocarbon-based PEMs, this group most likely has the largest variety of different systems. This is probably due to the wealth of prior knowledge of the nonsulfonated analogues that have been developed over the last several decades as well as the general expectation of higher thermal stability, better mechanical properties, and increased oxidative stability over polystyrene-based systems. Within the context of this section, polyarylenes are systems in which an aryl or heteroaryl ring is part of the main chain of the polymer. This section will, therefore, include polymers such as sulfonated poly (ether ether ketone) and sulfonated poly(imides) but will not include systems such as sulfonated polystyrene, which will be covered in Section 3.3.I.3. 

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