“…Poly(ether−ether−ketone) (PEEK, Scheme ) is one of the highest performance thermoplastics characterized not only by outstanding thermal, chemical, and mechanical properties but also by nonflammable properties and good processability. Therefore, PEEK has been used in the fields of electronics, automobile, chemical engineering, and others. − However, PEEK exhibits low T g and high crystallization speed resulting in nontransparent opaque materials and limiting its use in the optical and display fields where transparency of materials is required. Takata et al previously reported the synthesis of novel transparent poly(ether−ketone)s (PEKs) showing high solubility and thermal stability by polycondensation using 1,5-bis(4-halobenzoyl)-2,6-dimethylnaphthalene as dihaloarene. − Further, corresponding sulfur analogues poly(thioether−ketone)s (PTEKs) have also been reported to have similarly good properties in addition to inflammable and thermosetting properties. − 1 …”
Fluorene-based poly(ether-ether-ketone) (F-PEEK) was designed and synthesized by reacting a 9,9-diarylfluorene-containing biphenol and a naphthalene-containing dihaloarene. High molecular weight F-PEEK (M w > 270 000; M n ∼ 55 000) was obtained in quantitative yields by the two-step polycondensation of 9,9-bis-(4-hydroxy-3-methylphenyl)fluorene and 1,5-bis(4-fluorobenzoyl)-2,6-dimethylnaphthalene in the presence of cesium carbonate in diphenyl sulfone at 165 °C and then 220 °C. The chemical, physical, and optical properties of F-PEEK were evaluated. Good solubility of F-PEEK in ordinary organic solvents such as THF and chloroform was confirmed. F-PEEK exhibited a high refractive index of 1.64 at 589 nm, whereas it showed a much lower birefringence value than a polycarbonate or a polyester. F-PEEK was amorphous and transparent at room temperature. The transmittance of F-PEEK in film state was over 80% in the visible region. These optical properties were probably related to the cardo structure of the fluorene moiety placed on the main chain. No phase transition except for T g was confirmed in the DSC analysis. F-PEEK displayed a high storage modulus (E′ ) 2.93 GPa) and glass transition temperature (280 °C) in comparison with commercially available poly(ether-ether-ketone) (PEEK, E′ ) 1.73 GPa and T g 169 °C). The high modulus of F-PEEK was derived unambiguously from both the fluorene and naphthalene skeletons.
“…Poly(ether−ether−ketone) (PEEK, Scheme ) is one of the highest performance thermoplastics characterized not only by outstanding thermal, chemical, and mechanical properties but also by nonflammable properties and good processability. Therefore, PEEK has been used in the fields of electronics, automobile, chemical engineering, and others. − However, PEEK exhibits low T g and high crystallization speed resulting in nontransparent opaque materials and limiting its use in the optical and display fields where transparency of materials is required. Takata et al previously reported the synthesis of novel transparent poly(ether−ketone)s (PEKs) showing high solubility and thermal stability by polycondensation using 1,5-bis(4-halobenzoyl)-2,6-dimethylnaphthalene as dihaloarene. − Further, corresponding sulfur analogues poly(thioether−ketone)s (PTEKs) have also been reported to have similarly good properties in addition to inflammable and thermosetting properties. − 1 …”
Fluorene-based poly(ether-ether-ketone) (F-PEEK) was designed and synthesized by reacting a 9,9-diarylfluorene-containing biphenol and a naphthalene-containing dihaloarene. High molecular weight F-PEEK (M w > 270 000; M n ∼ 55 000) was obtained in quantitative yields by the two-step polycondensation of 9,9-bis-(4-hydroxy-3-methylphenyl)fluorene and 1,5-bis(4-fluorobenzoyl)-2,6-dimethylnaphthalene in the presence of cesium carbonate in diphenyl sulfone at 165 °C and then 220 °C. The chemical, physical, and optical properties of F-PEEK were evaluated. Good solubility of F-PEEK in ordinary organic solvents such as THF and chloroform was confirmed. F-PEEK exhibited a high refractive index of 1.64 at 589 nm, whereas it showed a much lower birefringence value than a polycarbonate or a polyester. F-PEEK was amorphous and transparent at room temperature. The transmittance of F-PEEK in film state was over 80% in the visible region. These optical properties were probably related to the cardo structure of the fluorene moiety placed on the main chain. No phase transition except for T g was confirmed in the DSC analysis. F-PEEK displayed a high storage modulus (E′ ) 2.93 GPa) and glass transition temperature (280 °C) in comparison with commercially available poly(ether-ether-ketone) (PEEK, E′ ) 1.73 GPa and T g 169 °C). The high modulus of F-PEEK was derived unambiguously from both the fluorene and naphthalene skeletons.
“…The effect of wear of UHMWPE-metal pairs on osteolysis and early loosening in total hip replacements has been reported in literature [13]; a polymer transfer layer was observed by Gispert et al [14] in UHMWPE-ASTM F138 pairs and by Li et al [15] in UHMWPE-ASTM F136 pairs after pin-on-disc tests similar to those described in the present work. Moreover, Watters [16] also found these transfer layers at the surface of ASTM F136 femoral heads in contact with UHMWPE liners, after experiments carried out in a conventional hip simulator.…”
“…The work by Hay et al and Chen et al has inspired great interest in incorporating carbazole derivatives into PAEKs. As industrially relevant thermoplastics, PEEKs, PAEKs and PASUs inherently possess good thermal stability and outstanding mechanical properties, 32,33 which make them applicable in various areas such as aviation, 34 dielectric films, 35 fuel cells 36 and so on. The introduction of rigid carbazole units into PAEK frameworks is expected to enhance the thermal properties of the obtained products, and such high-performance polymers would be highly advantageous for practical applications.…”
3,6-Diphenyl-9 H-carbazole pendants are grafted herein to poly(arylene ether ketone)s (PAEKs) via the Ullmann C–N coupling reaction. To the best of our knowledge, this is the first time that PAEKs containing a carbazole pendant (Cz) have been synthesized through the Ullmann C–N coupling reaction. The high molecular weights of PAEK-Cz (PAEKs with 3,6-diphenyl-9 H-carbazole pendants) are inherited from their precursors, owing to the high reactivity of their monomers. The obtained PAEK-Cz- x polymers exhibit good solubility in most common organic solvents and excellent thermal stabilities, with the 5% weight loss temperatures for all products being above 598°C under a nitrogen atmosphere. The glass transition temperatures are all above 199°C and can be controlled by adjusting the feed ratio of monomers. The polymer membranes obtained by the casting method are tough and thus have strong potential for practical applications.
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