Poly(aryl ether ketone)s with (3-methyl)phenyl and (3-trifluoromethyl)phenyl side groups

New bisphenol monomers, (3-methyl)phenylhydroquinone and (3-trifluoromethyl)phenylhydroquinone, were prepared in a two-step Synthesis. A series of poly(aryl ether ketone)s were derived from these bisphenols via a nucleophilic aromatic substitution polycondensation with various bisfluoro compounds. The polycondensation proceeded quantitatively in tetramethylene sulfone in the presence of anhydrous potassium carbonate and afforded the polymers with inherent viscosities of 0.63-0.91 dL/g. The fluorinated polymers showed lower glass-transition temperatures and higher thermal-decomposition temperatures than the corresponding nonfluorinated polymers. The solubility of the polymers was improved by the introduction of bulky pendant groups. All the polymers formed transparent, strong, and flexible films, with tensile strengths of 86.4-102.0 MPa, Young's moduli of 2.28-3.03 GPa, and elongations at break of 14-42%. All the polymers had low dielectric constants of 2.70-2.83 at 1 MHz. Compared with the methylated polymers, the trifluoromethylated polymers exhibited lower water sorption, which was attributed to the stronger hydrophobicity of the fluorine-containing groups. (C) 2002 Wiley Periodicals, Inc.