Structure Damage And Properties Of Functionalized Graphene/Polyaniline Composite Coatings Under ?-rays Environment

The synergistic effect of high temperature,high humidity and gamma rays exerts adverse impact on the service life of large equipment such as nuclear power plants or nuclear-powered ships.Therefore,it is necessary to protect the crucial components of equipments by multi-functional coating possessing excellent resistance to radiation damage and corrosion protection property simultaneously.Polyaniline coating exhibited promising antioxidant poperty and anticorrosion performance,which could be applied in such special circumstances after specific reinforcement.Graphene possesses large aspect ratio and excellent shielding effect on the diffusion of corrosive medium,and displays strong absorption and quenching ability towards the radicals generated by?-rays irradiation,is an outstanding reinforced material for coatings.Therefore in this paper,the graphene was modified to improve its radiation damage resistance property,and the obtained functionalized graphene was added to the polyaniline coating to improve the irradiation damage resistance and corrosion protection property of polyaniline coating under?-rays environment.The main research contents are as follows:?1?The irradiation damage of graphene oxide?GO?in water was investigated.The results of FTIR,Raman and XRD showed that the oxygen functional groups on the surface of GO decreased experiencing 100 kGy irradiation doses.After 500 kGy irradiation,the defect quantity of GO increased.The results of TEM and BET demonstrated that a large number of mesopores with a diameter of about 4 nm appeared on the GO layer,and the specific surface area of GO violently increased to 16 times of unirradiated GO.?2?The PGNS was prepared by two-step in-situ polymerization of polyaniline?referred to as PGO?on GO surface and dispersed in N-methylpyrrolidone?NMP?solution of polyaniline.The PGO was characterized by FTIR,Raman,XRD,AFM and XPS.The results revealed that polyaniline was uniformly distributed on the surface of GO.BET and TEM measurements demonstrate that the structural stability of PGO is much better than GO under?-rays environment.Based on the results of electrochemical tests,when the PGO content was 0.10 wt%,PGNS_0.10 achieved the best performance on irradiation damage resistance and corrosion protection property than the other mass ratios.ESR measurements also proved that PGNS_0.10 are not almost affected by adverse influence comes from active radicals,thus PGNS_0.10 exhibited prolonged service life under?-rays environment.?3?Polypyrrole?PPY?was modified on the surface of GO via in situ chemical oxidation,and the obtained nanocomposite material?YGO?was dispersed in polyaniline?NMP?solution.The YGO was characterized by FTIR,Raman,XRD and XPS.It was found that polypyrrole have been successfully modified on GO.Then,SEM and TEM were used to observe the morphology of YGO.Polypyrrole was found to be uniformly distributed and showed a"shredded piece"morphology with a dense structure.After receiving 500 kGy irradiation,there is none mesopores on the surface of YGO.Meanwhile,the BET data displays that the specific surface area of YGO_1:1?n?pyrrole?:n?GO?=1:1?was 1.05 times of unirradiated YGO_1:1?much less than 15.5 times of GO?.Electrochemical data demonstrated that the irradiation damage resistance and corrosion protection property of YGNS_0.25 are much better than others mass fraction YGNS and even PGNS_0.10.According to ESR measurement,the active radicals achieved the minimum concentration in YGNS_0.25 among the other mass ratios.In other words,the irradiation damage effect on YGNS_0.25.25 is the most weakest,which is consistent with the conclusion of electrochemical data.