SYNOPSISPolymerization of acrylamide was carried out with cerium( IV) -EDTA redox initiator system with and without electrolysis. The effect of temperature, time, cerium( IV), and EDTA concentrations on the polymerization yield and molecular weight were studied and compared with electrolytic conditions. At low concentrations of cerium( IV ) the electrolytic method continuously supplying Ce ( IV ) from Ce (111) has an advantage over the nonelectrolytic method for which polymerization did not occur under these conditions. A possible polymerization mechanism is suggested.

SYNOPSISAcrylamide polymerization by Ce ( IV) -polyaminocarboxylic acids, i.e., EDTA, DTPA, EGTA, and NTA, which have strong chelating properties, have been studied at different

Ce(IV) salt‐malonic acid or citric acid initiator systems were used for the polymerization of acrylamide in the presence of electrolysis. This allowed Ce(III) to be converted to Ce(IV) during polymerization. Graphite, silver, chromium/nickel, lead, platinum and stainless‐steel electrodes were used. The highest polymerization yield was obtained with a stainless‐steel electrode.

Acrylamide and acrylonitrile were polymerized with water-soluble organic reducing compounds containing hydroxy groups such as methyl cellulose (MC), methyl hydroxypropyl cellulose (MHPC) and poly(ethy1ene glyco1)s (PEG) in the presence of Ce(IV) in order to produce graft/block copolymers. The effect of cerium(1V) concentration, temperature, time and monomer concentration on the yield was studied. Copolymers of cellulose derivatives and polyacrylonitrile showed solubility properties similar to polyacrylonitrile. Both cellulose derivative-polyacrylamide and poly(ethy1ene glycol)polyacrylamide copolymers were soluble in water. ZUSAMMENFASSUNG:Acrylamid und Acrylnitril wurden in Gegenwart von Ce(V1)-Ionen und wasserloslichen organischen, reduzierenden, Hydroxygruppen enthaltenden Verbindungen wie Methylcellulose (MC), Methylhydroxypropylcellulose (MHPC) und Poly(ethyleng1y-ko1)en (PEG) zu Block-und Pfropfcopolymeren polymerisiert. Der Einflun der Ce(V1)-und Monomerkonzentration sowie der Polymerisationstemperatur und -zeit auf die Polymerisationsausbeute wurde untersucht. Die Copolymeren aus Cellulosederivaten und Polyacrylnitril zeigen ahnliche Losungseigenschaften wie Acrylnitrilhomopolymere. Sowohl die Cellulose/Polyacrylamidals auch die Poly(ethylenglykol)/Polyacrylamid-Copolymeren sind wasserloslich. 0 1994 Huthig & Wepf Verlag, Base1 CCC 0003-3146/94/$05.00

SYNOPSISPolymerization of acrylamide was carried out with potassium permanganate-malonic acid, potassium permanganate-tartaric acid, and potassium permanganate-citric acid redox initiator systems with and without electrolysis. The effect of potassium permanganate concentration, acrylamide concentration, and temperature on the polymerization yield was studied and molecular weights of polymers were determined and compared with electrolytic conditions. At low concentrations of potassium permanganate, continuously supplying Mn( 111) has an advantage over the nonelectrolytic method for which polymerization did not occur under these conditions.

Polymerization of acrylamide initiated with ceric(1V) ion in the presence of methionine, phenylalanine, serine and aspartic acid was investigated in sulfuric acid solution. Maximum yield was obtained at 70°C and sulfuric acid concentration of 0.16 mol/l. Both conductometric titration and FT-IR results showed that the resulting polymers contained carboxy end groups. According to these findings and previous studies in this field, a suitable polymerization mechanism was proposed. ZUSAMMENFASSUNG: Acrylamid wurde mit Ce(1V)-Initiator in Gegenwart von Methionin, Phenylalanin, Serin bzw. Aspartamsaure in verdunnter Schwefelsaure polymerisiert. Bei 70 "C und einer Schwefelsaurekonzentration von 0,16 mol/l wurde die groRte Ausbeute erzielt. Carboxy-Endgruppen in den Polymeren wurden sowohl durch konduktometrische Titration als auch durch FT-IR-Spektroskopie nachgewiesen. Ein geeigneter Reaktionsmechanismus wird aufgrund dieser Resultate sowie vorangegangener Untersuchungen vorgeschlagen. 0 1993 Huthig & Wepf Verlag, Basel CCC 0003-3146/93/%05.00

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