Electrochemical study of the corrosion behaviour of copper/low-density polyethylene microcomposite in the simulated uterine solution

摘要

The corrosion characteristics of five copper/low-density polyethylene (Cu/LDPE) microcomposite in the simulated uterine solution have been studied by the electrochemical measurements, XRD and FESEM. The critical threshold (composition from which the material changes from insulator to electrical conductor) of the Cu/LDPE microcomposite is between 50 wt.% and 60 wt.% copper microparticles’ loading. Five microcomposites have similar corrosion mechanism in the course of corrosion in simulated uterine solution. The intermediate products of them are mainly Cu2O. When corrosion of the microcomposite reaches stable, Cu2+ generated within composite disperses through solution path to penetrate to simulated uterine solution outside the microcomposite, and corrosion rate rises as the copper content in composite increases. Compared with the microcomposite with high copper content, the microcomposite with low copper content have high copper transformation ratio, almost no sediments and hardly possible passivation characteristic, but its corrosive rate is slower than the former. This paper also compared the corrosion behaviour of the composite and bulk copper in the simulated uterine solution; there were more insoluble subproducts in the corrosion process of bulk copper than the composite. The Cu/LDPE microcomposite is favorable to use as the novel material of intrauterine device, and the copper content in composite should be reduced as greatly as possible if only contraception requirement can be sufficient.