Flocculation and Rheological Characteristics of Graft Copolymers of Carboxymethyl Cellulose and Polyacrylamide
| Autor: | F E Okieimen, C O Okieimen |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2005 |
| Předmět: |
Multidisciplinary
Aqueous solution Polyacrylamide technology industry and agriculture carboxymethyls cellulose polyacrylamoide graft copolymers flocculation rheological characteristics carboxyméthyles cellulosiques polyacrylamide greffage de copolymères floculation caractéristiques Solution polymerization macromolecular substances Carboxymethyl cellulose chemistry.chemical_compound chemistry Graft polymer Polymerization Management of Technology and Innovation Polymer chemistry medicine Copolymer Cellulose medicine.drug |
| Zdroj: | Discovery and Innovation; Vol 16, No 3 (2004); 144-148 |
| ISSN: | 1015-079X |
| Popis: | Graft copolymers of carboxymethyl cellulose, CMC, (d.s. 0.5) and polyacrylamide have been synthesized using ceric ioninitiated solution polymerization technique. The performance of the graft copolymer samples as flocculating agents was examined in 0.15% (w/v) kaolin suspension as function dosage. The flocculating ability of the graft polymer samples was comparable with those of commercial flocculant/coagulant, particularly at relatively high flocculant dosage. It was found that the performance of the graft copolymer samples as flocculating agents depended more on the molecular weight of the grafted polyacrylamide chains than on the number of the synthetic polymer chains interpositioned on the backbone polymer. Viscosity measurement in aqueous medium (double distilled water) of CMC and its graft copolymer, and in the presence of mono-, di- and trivalent cations were carried out. The results showed that grafting polyacrylamide on CMC increased (by more than 50%) the viscosity of CMC, markedly reduced the extent of biodegradation of aqueous solution of the backbone polymer, and buffered the effect of temperature and cations on the viscosity of the polymer solution. Key Words: carboxymethyls cellulose, polyacrylamoide, graft copolymers, flocculation, rheological characteristics Resume Des greffes des copolymeres de carboxymethyle cellulosique, CMC (d.s. 0,5) et de polyacrylamide ont ete synthetises en utilisant la technique de polymerisation d\'une solution serique ionisee. Le pouvoir des echantillons utilises comme matieres agglutinantes du copolymere greffe, a ete etudie dans 0,15% (w/v) de suspension du kaolin employe comme dose habituelle. Le pouvoir agglutinant des echantillons du polymere greffe etait comparable a celui des agglutinants / coagulants commerciaux, particulierement a des doses relativement eleves d\'agglutinant. On a constate que le pouvoir agglutinant des echantillons du copolymere greffe depend plus du poids moleculaire des chaines greffees de polyacrylamide que du nombre de chaines synthetiques du polymere situe dans le polymere central. Des mensurations de la viscosite dans un milieu aqueux (eau bi-distillee) de la cellulose carboxymethylique et son copolymere greffe, et en presence des cations mono -, di et trivalents ont ete effectuees. Les resultats ont montre que le greffage du polyacrylamide sur la cellulose carboxymethylique augmente dans plus de 50%, la viscosite de la cellulose carboxymethylique et qu\'il reduit fortement le niveau de biodegradation de la solution aqueuse du polymere central, tout en neutralisant l\'action de la temperature et des cations sur la viscosite de la solution polymerique. Mots-cles: carboxymethyles cellulosiques, polyacrylamide, greffage de copolymeres, floculation, caracteristiques rheologiques. Discovery and Innovation Vol 16 (3&4) 2004: 144-148 |
| Databáze: | OpenAIRE |
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