Characterization and comparison of poly(aryl ether ketone)s containing dibenzoylbiphenyl moieties: Effects of changes in biphenyl substitution pattern on thermal and mechanical properties

Abstract

A monomer, 3,3′‐bis (4‐fluorobenzoyl) biphenyl, was prepared in high yield in two steps from inexpensive 3‐chlorobenzoyl chloride and fluorobenzene, and polymerized by nucleophilic displacement reaction with various bisphenol monomers in tetramethylene sulfone to produce a series of high molecular weight poly(aryl ether ketone)s containing 3,3′‐dibenzoylbiphenyl (DBBP) moieties. The spectroscopic, thermal, and thermomechanical properties of these polymers and related isomeric polymers having 2,2′‐and 4,4′‐DBBP units were determined and compared to study the effects of changes in the substitution pattern of the biphenyl unit. Except for the 2,2′‐DBBP series of polymers, Tgs were found to increase with increasing linearity of the DBBP unit. The 2,2′‐DBBP series of polymers had exceptionally high Tgs due to the sterically restricted motions in the biphenyl unit caused by the 2,2′‐substitution. In addition, they also showed evidence for torsion with the 2,2′‐DBBP unit, whereas in other isomeric polymers the DBBP units are believed to be relatively coplanar. Thermal stabilities and tensile moduli for these polymers proved to be independent of substitution patterns. © 1995 John Wiley & Sons, Inc.

Synthesis of poly(p‐phenylene) macromonomers and multiblock copolymers

“…End‐capping agent 4‐chloro‐4′‐fluorobenzophenone was synthesized by an iron(III)chloride‐catalyzed Friedel–Crafts acylation of chlorobenzene with 4‐fluorobenzoyl chloride in 50% yield. Moulinie et al8 prepared and used this molecule in the synthesis of 4,4′‐bis(4‐fluorobenzoyl)biphenyl that was subsequently polymerized with various bisphenol monomers to produce high molecular weight polyaryletherketones. 2,5‐Dichloro‐4′‐methylbenzophenone was chosen as the monomer for its ability to achieve high molecular weights via Ni(0) coupling, excellent thermal properties of poly(4′‐methyl‐2,5‐benzophenone), and because of the ability of the methyl group to serve as a 1 H NMR spectroscopic label for macromonomer characterization.…”

“…Found: C, 63.55%; H, 4.08%. 4‐Chloro‐4′‐fluorobenzophenone8 was recrystallized from ethanol. E LEM .…”

“…13 C NMR (50.3 MHz): 197.6–197.2, 194.6, 165.0 (d, 1 J CF = 255.1 Hz), 143.8, 139.8, 139.0, 136.0, 134.5, 133.7, 132.4, 130.6, 130.1, 128.8, 127.3, 127.0, 115.4 (d, 2 J CF = 21.3 Hz), 21.6 ppm. The data for polymer 6 are reported elsewhere 8…”

Poly(aryl ether ketone)s containing dibenzoylbiphenyl groups: dynamic mechanical and physical ageing behaviour

“…The dynamic mechanical glass transition temperatures are in good agreement with those reported previously for the same polymers measured by DSC. 8 The higher T g values observed for the 2,2'-substituted polymers result from the steric hindering effect of the ortho substitution on chain rotation, and this effect has been correlated with the core angle between the points of substitution for similar polymers. 9 Increasing the bulk and stiffness of the connecting unit shifts the T g to higher temperatures, and this is particularly signi®cant in the case of the¯uorenyl connector group (e) where the T g exceeds 200°C.…”

Synthesis and photoluminescence study of hyperbranched poly(arylene ether ketone) nanocomposites containing cadmium sulfide nanoparticles

“…Poly(arylene ether ketone) (PAEK) is an important high performance engineering thermoplastics with extensive applications in aeronautic, automotive, and electric industries owing to its excellent mechanical properties, thermal stability, and good chemical resistance [17][18][19]. There are few reports on the templated synthesis of CdS in HPAEK copolymers.…”