Synthesis of copolymers suitable for the storage and slow release of reactants. Cases of copper salts for intra-uterine devices

This research has been carried out to determine whether a grafted poly(ethylene-vinyl acetate) matrix could be prepared which would release useful amounts of copper salts when used in intra-uterine devices. Intra-uterine devices were prepared by grafting hydroxyethyl acrylate onto ethylene-vinylacetate copolymers (EVA). The kinetics of the grafting reaction were studied. The grafting reaction was initiated by cobalt 60 gamma rays using the simultaneous method. The conditions of copper salts absorption by the grafted copolymers were selected. The average quantity of copper salts released daily from the intra-uterine device was meaured as a function of grafting ratio and the amount of copper salt initially incorporated in the grafted polymeric matrix. In vitro experiments samples showed constant release rates during a period of 18 months