الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
In the present work, the factors affecting the grafting of o(-bromoacrylic acid onto cellulose induced by Ce4+ were investigated. The variables studied were the initiator
concentration, the reaction temperature, the kind of the
inorganic acid used as well as its concentration.
Regarding the initiator concentration, the grafting is
characterized by the initial fast rate which reaches a
maximum (78%) then decreased gradually by increasing the
Ce4
+ concentration. Also, the kind of the Ce4+ plays a
role on grafting. Thus, in case of Ce4+ obtained by using
ceric ammonium sulphate, the maximum was reached at a concentration
of 10 m Mole Ce4+, while using ceric ammonium
nitrate the maximum was reached at Ce4+ concentration of
20 m Mole.
Concerning the reaction temperature, the grafting
reactions were carried out at 3 different temperatures:400,
60° and 800C. It was found that increasing the reaction
temperature causes a decrease of the percent grafting in
the systems of water and nitric acid, whereas in case of the systems containing hydroc~~oric, sulphuric and perchloric acids the percent grafting increased by increasing the reaction temperature In the systems containing nitric, hydrochloric sulphuric or perchloric acids, it is clear that the percent grafting increases at the initial stage in each system and gives a maximv~ at a certain time, then increases steadily with increasing time The effect of the concentration of the inorganic acid was also studied. Thus, the grafting reactions were carried out in presence of 0.05 N, 0.1 Nand 0.2 N acid concentrations and it is clear that increase of the acid concentration causes a decrease in the percent grafting. However, in most cases, low yields of grafting are obtained on using acid concentration more than 0 •.1 N. Attempts to determine the percent grafting by bromine analysis failed because intramolecular lactone formation has taken place during grafting reaction. This was confirmed by studying the infrared spectra of both 0< -bromoacrylic acid and the grafted cellulose.