الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
A number of functionalized polymers containing pesticide active groups have been prepared for the purpose of developing ideal controlled release formulations for herbicides. The synthetic route chosen for these polymers involved preparation of the pesticide active monomers containing 2,4- dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-methylphenoxy-acetic acid (MCPA) via ester or amide linkages. The resulting monomers have been polymerized through condensation reactions with a number of dicarboxylic acids or hexamethylenediisocyanate to give the corresponding linear polyester or polyurethane, respectively. The resulting linear polymers were subjected to further reaction with hexamethylenediisocyanate to give the corresponding insoluble crosslinked polymers.
Chemical modification techniques were also used to attach 2,4-D to the preformed amine - containing polyester via covalent amide linkage.
The releases of 2,4-D from polymeric 2,4-D through hydrolysis reaction •ere carried out at different pH media, including acidic (pH=4), neutral (pH=6.7) and alkaline (pH=9) conditions, at 30°C. The amount of 2,4-D released was determined by U.V spectrophotometric analysis. The results obtained from the hydrolysis studies of these functionalized polymers, indicated that several factors appeared to be affecting the rates of release of active moieties. These factors include the nature of the hydrolysing medium, fie strength , and type, of the active agent - polymer bond