Preparation and properties of aromatic polyamides from 1,4-bis(p-carboxyphenoxy)naphthyl and aromatic diamines

✍ Scribed by Guey-Sheng Liou; Sheng-Huei Hsiao

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 188 KB
• Volume: 35
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(199708)35:11<2273::aid-pola18>3.0.co;2-b

✦ Synopsis

A new aromatic dicarboxylic acid, 1,4-bis(p-carboxyphenoxy)naphthyl (3), was synthesized by the reaction of p-fluorobenzonitrile with 1,4-naphthalenediol, followed by hydrolysis. Aromatic polyamides having inherent viscosities of 1.27-2.22 dL/ g were prepared by the triphenyl phosphite activated polycondensation of diacid 3 with various aromatic diamines. Most of the resulting polymers showed an amorphous nature and were readily soluble in a variety of organic solvents including N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), and m-cresol. Transparent, tough, and flexible films of these polymers could be cast from the DMAc or NMP solutions. The cast films had tensile strengths ranging from 64-104 MPa, elongations-at-break from 6 to 10%, and initial moduli from 1.52 to 2.14 GPa. These polyamides had glass transition temperatures in the range of 195 to 240ЊC. Almost all polymers were thermally stable up to 400ЊC, with 10% weight loss being recorded above 480ЊC in air and nitrogen atmospheres.