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A new diamine, 4-(4-trifluoromethylphenyl)-2,6-bis(4-aminophenyl)pyridine, was synthesized and used in the preparation of the fluorinated polyamides with inherent viscosities of 0.67–0.96 dL g−1 by direct polycondensation with aromatic dicarboxylic acids. The obtained polyamides have good solubility in many organic solvents such as N-methyl-2-pyrrolidinone, dimethylacetamide (DMAc), and tetrahydrofuran and exhibited glass transition temperatures between 275°C and 301°C, 10% weight loss temperatures ( Td10s) ranging from 502°C to 516°C, and char yields of 51–61% at 800°C under nitrogen atmosphere. Flexible and strong polymer films cast from DMAc solutions showed tensile strengths of 77.4–93.2 MPa, elongations at break of 9.2–14.3%, and initial moduli of 2.06–2.82 GPa. The polymer films also had good dielectric properties with dielectric constants of 3.22–3.50 (1 M Hz) and dissipation factors of 3.20–3.96 × 10−3, and acceptable electrical insulating properties, as well as low water uptake between 1.26% and 1.78%, and high transparency with an ultraviolet–visible absorption cutoff wavelength in the range of 330–371 nm. The remarkable combined features ensure these polymers to be ideal candidate materials for advanced microelectronic industry and other related applications.

Poly(aryl ether ketone)s (PAEKs) are a class of high‐performance engineering thermoplastics known for their excellent combination of chemical, physical and mechanical properties, and the synthesis of semicrystalline PAEKs with increased glass transition temperatures (Tg) is of much interest. In the work reported, a series of novel copolymers of poly(ether ketone ketone) (PEKK) and poly(ether amide ether amide ether ketone ketone) were synthesized by electrophilic solution polycondensation of terephthaloyl chloride with a mixture of diphenyl ether and N,N′‐bis(4‐phenoxybenzoyl)‐4,4′‐diaminodiphenyl ether (BPBDAE) under mild conditions. The copolymers obtained were characterized using various physicochemical techniques. The copolymers with 10–35 mol% BPBDAE are semicrystalline and have markedly increased Tg over commercially available poly(ether ether ketone) and PEKK due to the incorporation of amide linkages in the main chain. The copolymers with 30–35 mol% BPBDAE not only have high Tg of 178–186 °C, but also moderate melting temperatures of 335–339 °C, having good potential for melt processing. The copolymers with 30–35 mol% BPBDAE have tensile strengths of 102.4–103.8 MPa, Young's moduli of 2.33–2.45 GPa and elongations at break of 11.7–13.2%, and exhibit high thermal stability and good resistance to organic solvents. Copyright © 2010 Society of Chemical Industry

Two novel monomers, 9,9-bis[4-(4-carboxyphenoxy)phenyl]xanthene (BCAPX) and 9,9-bis[4-(4-aminophenoxy)phenyl]xanthene (BAPX) were prepared in two main steps starting from nucleophilic substitution of 9,9-bis(4-hydroxyphenyl)xanthene (BHPX) with p-fluorobenzonitrile and p-chloronitrobenzene, respectively. Using triphenyl phosphite and pyridine as condensing agents, two series of polyamides containing xanthene cardo groups with the inherent viscosities (0.82-1.32 dL/g) were prepared by polycondensation from BCAPX with various aromatic diamines or from BAPX with various aromatic dicarboxylic acids in an N-methyl-2-pyrrolidone (NMP) solution containing dissolved calcium chloride, respectively. All new polyamides were amorphous and readily soluble in various polar solvents such as N,N-dimethylformamide (DMF), NMP, N,N-dimethylacetamide (DMAc) and pyridine. These polymers showed relatively high glass transition temperatures between 264 and 308 C, decomposition temperatures at 10% weight loss ranging from 502 to 540 C and 488 to 515 C in nitrogen and air, respectively, and char yields at 800 C in nitrogen higher than 56%. Transparent, flexible, and tough films of these polymers cast from DMAc solutions exhibited tensile strengths ranging from 86 to 109 MPa, elongations at break from 13 to 22%, and initial moduli from 2.15 to 2.63 GPa.