Complexation of poly(vinylpyrrolidone) and gelatin with some transition metal chlorides in aqueous solution

✍ Scribed by A. Güner; A. U. Sevil; O. Güven

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 125 KB
• Volume: 68
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19980509)68:6<891::aid-app3>3.0.co;2-c

✦ Synopsis

Complexation of poly(vinylpyrrolidone) and gelatin with certain metal chlorides (HgCl 2 , CdCl 2 , CoCl 2 , and ZnCl 2 ) have been investigated by viscosimetric and spectrophotometric techniques in aqueous solutions. While the change in intrinsic viscosity, [h], of poly(vinylpyrrolidone) has shown a discontinuity with a concentration of metal chlorides, gelatin showed a steady decrease with increasing metal chloride concentration. The decreasing order of effectiveness of cations in complex formation is Hg 2/ ú Cd 2/ ú Co 2/ ú Zn 2/ for poly(vinylpyrrolidone) and Zn 2/ ú Co 2/ ú Cd 2/ ú Hg 2/ for gelatin solutions. It has been suggested that the poly(vinylpyrrolidone)/ metal cation interaction is a charge-controlled reaction, and gelatin/metal cation is a covalent coordination in character. A similar metal cation effect has been observed for poly(vinylpyrrolidone) by UV-VIS spectrophotometry.