Preparation and absorption spectrum studies of aromatic and alicyclic poly(amide acid) ammonium salts in water and DMF and in films

✍ Scribed by Qinghua Li; Takashi Yamashita; Kazuyuki Horie; Hiroshi Yoshimoto; Takao Miwa; Yasunari Maekawa

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 381 KB
• Volume: 36
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(199806)36:8<1329::aid-pola16>3.0.co;2-8

✦ Synopsis

A series of ammonium salts of poly(amide acid)s (PAS) were prepared from various poly(amide acid)s (PAA) with tertiary amines. The solubility of poly-(amide acid) ammonium salts prepared from PAA(PMDA/ODA) in water is related to the ion concentration of tertiary amines. In order to elucidate the influence of the chemical structures of poly(amide acid)s and poly(amide acid) ammonium salts on their absorption spectra, pyromellitic dianhydride (PMDA), 3,3 ,4,4-biphenyltetracarboxylic dianhydride (BPDA), and 3,3 ,4,4-benzophenonetetracarboxylic dianhydride (BTDA) were chosen to react with p-phenylenediamine (PDA) and (4,4 -diaminodicyclohexyl)methane (DCHM) to give three kinds of aromatic PAAs and three kinds of alicyclic PAAs. The corresponding PASs were prepared by the reaction of PAAs with triethanolamine (TEA). Their ultraviolet-visible (UV-vis) absorption spectra were investigated compared to those of model compounds. A transparent film without absorption above 320 nm was obtained for PAS(PMDA/DCHM). The difference in absorption spectra of PAS(PMDA/PDA) from that of PAS(PMDA/DCHM) can be related to the existence of intra-and intermolecular charge transfer (CT) for PAS(PMDA/PDA). The absorption spectra of PASs with PDA in films are red shifted compared to those of corresponding PAAs in films, while the absorption spectra of PASs in water are blue shifted compared to those of corresponding PAAs in DMF. No differences in the absorption spectra of PAAs and PASs were found in DMF/H 2 O (9/1) mixed solvent. ᭧ 1998