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Periodate oxidized cellulose was grafted with methyl methacrylate using hydrazine hydrate in presence and absence of Cu++. The grafting reaction was favoured in presence of Cu++ and it was advantageous to treat first the cellulose material with copper sulphate solution rather than to incorporate it in the polymerization system. The graft yields depended upon the concentrations of copper sulphate and hydrazine hydrate, pH, temperature, and time of polymerization as well as degree of oxidation of cellulose. There were optimal concentrations of copper sulphate (6–8 mmol/l) and hydrazine hydrate (2 mmol/l). A polymerization medium of pH 6 and a temperature of 60°C constituted to optimal pH and temperature for grafting. Oxidized cellulose proved to be more amenable to grafting as compared with unoxidized cellulose and the magnitude of grafting relied on the degree of oxidation. A tentative mechanism was also suggested for grafting of cellulose substrates with a vinyl monomer using a Cu++‐hydrazine hydrate redox system.

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Carboxymethyl cellulose (CMC) was treated with HCl at 8OoC for different time periods (15-60 min). The hydrolyzed CMC samples as well as the original sample were graft copolymerized with acrylamide using &qQ as initiator. It was disclosed that the increasing duration of acid hydrolysis is accompanied by a progressive increment in the copper number of CMC, meanwhile its carboxyl content decreases. Acid hydrolysis enhances significantly the susceptibility of the CMC toward grafting. The latter reduces the copper number of the hydrolyzed CMC samples most probably via conversion of the aldehydic to carboxylic groups under the action of &&Q during grafting. Grafting also reduces the carboxyl content of the original CMC sample while increasing those of the hydrolyzed CMC samples. Methylolation of the polyacrylamide-CMC graft copolymers results in reactive finishes. When the latter were applied to cotton fabric according to the conventional pad-dry-cure method followed by a thorough washing, the fabric retained ca. 86% of the finish derived from the copolymer of CMC and 92% of finishes derived from the copolymers of hydrolyzed CMC. ZUSAMMENFASSUNG:Carboxymethylcellulose (CMC) wurde bei 80 "C unterschiedlich lange (15 -60 min) mit HCl behandelt. Sowohl die hydrolysierten CMC-Proben als auch die urspriingliche Probe wurden mit Acrylamid unter Verwendung von &qQ als Initiator gepfropft. Es zeigte sich, daR mit zunehmender Hydrolysezeit die Kupferzahl der CMC anstieg, wtlhrend der Carboxylgehalt dagegen abnahm. Die saure Hydrolyse erhshte die Empfindlichkeit der CMC gegeniiber Pfropfung bedeutend. Die Pfropfung redu-* Part 11: cf. ref?.

The effect of the introduction of aliphatic nitro, aromatic nitro and aromatic amino groups in the molecular structure of cotton cellulose on the susceptibility of the latter towards grafting with acrylonitrile using ceric ion as an initiator was investigated. The presence of nitro groups in the cellulose molecule reduced significantly the rates of both grafting and ceric consumption. The same situation was encountered with cellulose bearing aromatic nitro groups. Converting them to aromatic amino groups reduced grafting and significantly increased ceric consumption. A reaction mechanism was postulated to explain this discrepancy.