N-vinylimidazole-N-vinyl-2-pyrrolidone copolymers. Part I. Reactivity ratios, solubility and viscosimetric study

✍ Scribed by Martínez-Piña, Francisco; Gargallo, Ligia; Radić, Deodato

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 232 KB
• Volume: 47
• Category: Article
• ISSN: 0959-8103
• DOI: 10.1002/(sici)1097-0126(199811)47:3<340::aid-pi64>3.0.co;2-t

✦ Synopsis

Copolymers of N-vinylimidazole (VI) with N-vinyl-2-pyrrolidone (VP), (VI-co-VP) were obtained by radical polymerization using a,a@-azobisisobutyronitrile as initiator. The copolymers were characterized by 1H NMR and viscosimetric measurements. The monomer reactivity ratios were estimated to be r 1 \ for VP and for VI by the FinemanÈRoss and KelenÈTu dos linear 1É00 r 2 \ 0É07 procedures. These parameters were also estimated using a computer program based on a non-linear minimization algorithm (NLMA) starting from the values of and obtained by the linear procedures. All copolymers could be conr 1 r 2 sidered as random. The solubility in chloroform, n-butanol and n-propanol depends on the copolymer composition. Water, methanol and ethanol are solvents, irrespective of the copolymer compositions. The viscosimetric behaviour of unfractionated copolymers of one composition was studied in dilute solution in water (pH 2É0 and 6É0) at 0É01 M (NaCl) ionic strength and in methanol. Society of Chemical Industry Polym. Int. 47, 340È344 (1998)