Preparation and application of core-shell Fe3O4/polythiophene nanoparticles

The Fe3O4/polythiophene nanoparticles, possessing core-shell structure, were prepared by two-step method. In the first step, the Fe3O4 particles were synthesized via co-precipitation of FeCl3 and FeSO4, using the NH3 center dot H2O and N2H4 center dot H2O as precipitant system. In the second step, the thiophene adsorbed and polymerized on the surface of the Fe3O4 in the solvent of chloroform. Raman, FTIR, EDS, XRD, TEM, Zeta potential measurement and TG-SDTA were employed to characterize the composition and structure of the products. The results showed that the Fe3O4/polythiophene nanoparticles were successfully synthesized with good dispersion and stable core-shell structure, provided with average particle size of approximately 20 nm, in which the diameter of Fe3O4 core was approximately 14 nm and the thickness of polythiophene shell was approximately 3-4 nm. Then, the nanoparticles were added into alkyd varnish to prepare a composite coating. The neutral salt spray test, paraffin control test and mechanical test were carried out to identify the properties of the composite coating. It was found that the composite coating had good performances of anticorrosion and paraffin controlling when the mass fraction of the nanoparticles was 0.8-1 wt% in alkyd varnish. As a multifunctional material, the Fe3O4/polythiophene nanoparticles can be used in the internal coating of pipeline and have great potential application in crude oil pipeline transportation.