Graft copolymer (chitosan-g- N-vinyl formamide): Synthesis and study of its properties like swelling, metal ion uptake and flocculation

• Published in: Carbohydrate polymers Vol. 74; no. 3; pp. 632 - 639
• Main Authors: Mishra, Dinesh Kumar, Tripathy, Jasaswini, Srivastava, Abhishek, Mishra, Madan Mohan, Behari, Kunj
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 04.11.2008; Elsevier Science
• Subjects: amides; Applied sciences; chemical structure; Chitosan; composite polymers; cyclohexanone; duration; Exact sciences and technology; flocculation; ions; metals; N-vinyl formamide; Natural polymers; Physicochemistry of polymers; polymer grafting parameters; polymerization; potassium bromate; Potassium bromate/cyclohexanone; reaction mechanisms; sorption; Starch and polysaccharides; swelling (materials); synthesis; temperature; Thermal analysis; vinyl compounds; Potassium bromate/cyclohexanone; Chitosan; Thermal analysis; N-vinyl formamide; Vinyl derivative copolymer; Bromates; Graft copolymer; Metal ion; Grafting; Optimization; Thermal stability; Binding capacity; Cyclohexanone; Flocculation reagent; Coal; Reaction mechanism; Swelling; Experimental study; Organic adsorbent; Operating conditions; Chitosan derivatives; Flocculation; Preparation; Oside polymer; Divalent metal
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2008.04.015

A graft copolymer of chitosan and N-vinyl formamide has been synthesized by free radical polymerization using bromate/cyclohexanone redox in an inert atmosphere. The grafting ratio, add on, and efficiency increase continuously with increase in concentration of N-vinyl formamide from 9 × 10 −2 mol dm −3 to 41 × 10 −2 mol dm −3, bromate ion from 0.4 × 10 −2 mol dm −3 to 2.4 × 10 −2 mol dm −3 and chitosan from 0.6 g dm −3 to 1.4 g dm −3. Grafting parameters decrease with increase in concentration of hydrogen ion from 2 × 10 −3 mol dm −3 to 10 × 10 −3 mol dm −3. Experimental results also show that these parameters i.e. grafting ratio, add on, and efficiency increase with increase in cyclohexanone concentration from 0.4 × 10 −2 mol dm −3 to 1.2 × 10 −2 mol dm −3, but beyond this cited range, these parameters decrease. Maximum grafting i.e. 189.5% has been found at 120 min and 40 °C. The swelling, metal ion sorption and flocculation capability have been studied, respectively. The flocculation capability of chitosan and chitosan-g- N-vinyl formamide in both coking and non-coking coals has been studied for the treatment of coal mine waste water. The graft copolymer has been characterized by Infra red (IR) spectroscopy and thermogravimetric analysis.