title: Novel PEPA-functionalized graphene oxide for fire safety enhancement of polypropylene.
abstract: Polypropylene (PP) is a general-purpose plastic, but some applications are constrained by its high flammability. Thus, flame retardant PP is urgently demanded. In this article, intumescent flame retardant PP (IFRPP) composites with enhanced fire safety were prepared using 1-oxo-4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane (PEPA) functionalized graphene oxide (PGO) as synergist. The PGO was prepared through a mild chemical reaction by the covalent attachment of a caged-structure organic compound, PEPA, onto GO nanosheets using toluene diisocynate (TDI) as the intermediary agent. The novel PEPA-functionalized graphene oxide not only improves the heat resistance of GO but also converts GO and PEPA from hydrophobic to hydrophilic materials, which leads to even distribution in PP. In our case, 7 wt% addition of PGO as one of the fillers for IFRPP composites significantly reduces its inflammability and fire hazards when compared with PEPA, by the improvement of first release rate peak (PHRR), total heat release, first smoke release rate peak (PSRR) and total smoke release, suggesting its great potential as the IFR synergist in industry. The reason is mainly attributed to the barrier effect of the unburned graphene sheets, which protects by the decomposition products of PEPA and TDI, promotes the formation of graphitized carbon and inhibits the heat and gas release.
authors.affiliation: School of Chemistry & Chemical Engineering, Guangzhou University, Guangzhou 510006, People's Republic of China.
authors.forename: Jia You
authors.initials: JY
authors.lastname: Xu
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.affiliation: School of Chemistry & Chemical Engineering, Guangzhou University, Guangzhou 510006, People's Republic of China.
authors.forename: Kai Dan
authors.initials: KD
authors.lastname: Li
authors.affiliation: Guangxi Key Laboratory of Information Material, Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Materials, School of Material Science and Engineering, Guilin University of Electronic Technology, Guilin, 541004, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Miao
authors.affiliation: Guangxi Key Laboratory of Information Material, Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Materials, School of Material Science and Engineering, Guilin University of Electronic Technology, Guilin, 541004, People's Republic of China.
authors.forename: Sakae
authors.initials: S
authors.lastname: Tanemura
keywords: PEPA; fire safety; graphene oxide; intumescent flame retardant; polypropylene