Synthesis of high molecular weight polyacrylamide flocculant by radiation polymerization. [Dose rate of 6. 2 x 10/sup 2/ rad/hr;. gamma. radiation]

Journal Article · Wed Dec 01 04:00:00 EST 1976 · J. Appl. Polym. Sci.; (United States)

DOI:https://doi.org/10.1002/app.1976.070201204· OSTI ID:7120856

Wada, T; Sekiya, H; Machi, S

The radiation-induced polymerization of acrylamide was studied to prepare a high molecular weight and highly effective polyacrylamide flocculant. Among various solvents, mixtures of water--tert-butyl alcohol and water--acetone were found to be suitable for the synthesis of the high molecular weight polyacrylamide. For polymerization in acetone--water mixtures, the molecular weight of polymer increases with monomer concentration; but at the high concentration intermolecular imidation of amide groups tends to take place during the polymerization to form crosslinked and water-insoluble polymer. The water-soluble polymer with the largest molecular weight of 6.7 x 10/sup 6/ is produced in the polymerization with monomer concentration of 2.91 moles/l at 0/sup 0/C at a dose rate of 6.2 x 10/sup 2/ rad/hr in acetone--water mixture containing 60 vol. percent water. The crosslinking of polymer or the formation of water-insoluble polymer could be avoided by the addition of K/sub 2/CO/sub 3/ or NaOH to raise the pH of the reaction mixture above 6.5. The flocculation effects were evaluated from sedimentation speed of kaolin suspension and transparency of the separated water. The sedimentation speed is proportional to the intrinsic viscosity of the polymer in the range of 4 to 23 dl/g. The polymers prepared in this study show much higher sedimentation speed than commercial polyacrylamide flocculants. The transparency of the separated water is higher than 93 percent, similar to the results with commercial flocculants.

• Research Organization: Japan Atomic Energy Research Inst., Takasaki Gunma
• OSTI ID: 7120856
• Journal Information: J. Appl. Polym. Sci.; (United States), Journal Name: J. Appl. Polym. Sci.; (United States) Vol. 20:12; ISSN JAPNA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400600* -- Radiation Chemistry
ACETONE
ACRYLAMIDE
ALCOHOLS
AMIDES
BUTANOLS
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
DOSE RATES
ELECTROMAGNETIC RADIATION
FLOCCULATION
GAMMA RADIATION
HYDROXY COMPOUNDS
IONIZING RADIATIONS
KETONES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PH VALUE
POLYMERIZATION
PRECIPITATION
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS
SEPARATION PROCESSES
SOLVENT PROPERTIES
TEMPERATURE DEPENDENCE