Complexation of sequence-ordered methacrylic acid copolymers with poly(4-vinylpyridine)

✍ Scribed by Yoshihito Inai; Shin-Ichiro Kato; Tadamichi Hirabayashi; Kenji Yokota

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 634 KB
• Volume: 34
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19960915)34:12<2341::aid-pola8>3.0.co;2-z

✦ Synopsis

The complexation of three kinds of sequence-ordered acid (co)polymers with a base homopolymer was studied. The acid polymers used are poly(methacry1ic acid) 1, alternating (1 : 1) ethylene-methacrylic acid copolymer 2, and periodic (2 : 1) ethylene-methacrylic acid copolymer 3, and the base polymer is poly(4-vinylpyridine) 4. When mixing a methanol solution of 1,2, or 3 with that of 4 (0.1M of each functional group), precipitate was formed immediately for all polymer pairs. All the precipitates contained carboxyl and pyridyl groups in ca. 1 : 1 molar ratio and showed IR spectra indicating the hydrogen bonding between carboxyl and pyridyl groups. When mixing dilute methanol solutions ( w 4 M ) of the above polymer pairs, no precipitation was observed, but the extinction coefficient (cB) a t 255 nm of pyridyl groups in 4 was found to increase with an increasing acid polymer concentration. This is ascribed to hydrogen bonding between carboxyl and pyridyl groups in methanol. Based on the cB variation, the order of complexation constants for acid/base polymer pairs was estimated as follows: 114 pair -214 pair % 314 pair.