Synthesis, characterization, flocculation, and rheological characteristics of hydrolyzed and unhydrolyzed polyacrylamide-grafted poly(vinyl alcohol)

✍ Scribed by S. Krishnamoorthi; R. P. Singh

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 168 KB
• Volume: 101
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.21755

✦ Synopsis

Abstract

Graft copolymers of poly(vinyl alcohol) and polyacrylamide (PVA‐g‐PAM) were synthesized using a ceric ion–induced solution polymerization technique at 28°C. Three grades of graft copolymers were synthesized with varying acrylamide concentrations. Three grades of hydrolyzed products of PVA‐g‐PAM were synthesized with varying concentrations of sodium hydroxide solution. Hydrolyzed and unhydrolyzed PVA‐g‐PAM were characterized by viscometry, X‐ray diffractometry, infrared spectroscopy, and thermal analysis. Rheological investigation was also carried out on the aqueous solutions of various samples. The flocculation characteristics of various materials were investigated by the use of jar and settling tests in 0.25 and 5 wt %, respectively, using kaolin and iron ore suspensions. Among the series of graft copolymers, the one with fewest but longest PAM chains showed superior performance. The flocculation characteristics of the best‐performing graft copolymer were compared with those of various commercially available flocculants in the two suspensions under investigation. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2109–2122, 2006