Fluorinated polyamides and poly(amide imide)s based on 1,4‐bis(4‐amino‐2‐trifluromethylphenoxy)benzene, aromatic dicarboxylic acids, and various monotrimellitimides and bistrimellitimides: Syntheses and properties

Abstract

A CF3‐containing diamine, 1,4‐bis(4‐amino‐2‐trifluromethylphenoxy) benzene (I), was prepared from hydroquinone and 2‐chloro‐5‐nitrobenzotrifluoride. Imide‐containing diacids (Va–h and VIa,b) were prepared through the condensation reaction of amino acids, aromatic diamines, and trimellitic anhydride. Then, a series of soluble fluorinated polyamides (VIIa–h) and poly(amide imide)s (VIIIa–h and Xa,b) were synthesized from I with various aromatic diacids (IIa–h) and imide‐containing diacids (Va–h and VIa,b) via direct polycondensation with triphenyl phosphate and pyridine. The polyamides and poly(amide imide)s had inherent viscosities of 1.00–1.70 and 0.79–1.34 dL/g, respectively. All the synthesized polymers showed excellent solubility in amide‐type solvents such as N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide, and N‐dimethylformamide and afforded transparent and tough films via solvent casting. Polymer films of VIIa–h, VIIIa–h, and Xa,b had tensile strengths of 91–113 MPa, elongations to break of 8–40%, and initial moduli of 2.1–2.8 GPa. The glass‐transition temperatures of the polyamides and poly(amide imide)s were 254–276 and 255–292 °C, respectively, and the imide‐containing poly(amide imide)s had better thermal stability than the polyamides. The polyamides showed higher transparency and were much lighter in color than the poly(amide imide)s, and their cutoff wave numbers were below 400 nm. In comparison with isomeric IXc–h, poly(amide imide)s VIIIc–h exhibited less coloring and showed lower yellowness indices. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3116–3129, 2004

In-situ preparation of poly(ether imide)/amino functionalized silica mixed matrix membranes for application in enzyme separation

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Synthesis and properties of novel soluble polyamides containing both fluorene or xanthene cardo moieties and fluorinated phenoxy pendant groups

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