Halochromism of N-phenoxide betaine dye in salt-containing poly(ethylene oxide) oligomers

✍ Scribed by Hiroyuki Ohno; Hisashi Kawanabe

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 506 KB
• Volume: 7
• Category: Article
• ISSN: 1042-7147
• DOI: 10.1002/(sici)1099-1581(199609)7:9<754::aid-pat553>3.0.co;2-5

✦ Synopsis

The polarity of poly(ethy1ene oxide) (PEO) oligomers and PEOlsalt mixed system was analyzed as the negative solvafochromism and halochromism of betaine dye,

2,6-diphenyE-4-(2,4,6-triphenylpyridinio) phenolate (1).

The polarity of PEO oligomers, detected as the shift of the absorption maximum of the dye (l), decreased with increasing PEO chain length, reflecting the terminal hydroxyl group fraction. The polarity of the PEO mafrix was the function of both lattice energy and cation radius of the added salt under the same salt concentration. There is a clear relation between the absorption maximum and the lattice energy of a series of salts having the same cation. The lattice energy of most salts was suggested to be estimated empirically by this relation.