title: Graphitic carbon nitride/phosphorus-rich aluminum phosphinates hybrids as smoke suppressants and flame retardants for polystyrene.
abstract: Graphitic carbon nitride/organic aluminum hypophosphites (g-C3N4/OAHPi) hybrids, i.e., CPDCPAHPi and CBPODAHPi, were synthesized by esterification and salification reactions, and then incorporated into polystyrene (PS) to prepare composites through a melt blending method. Structure and morphology characterizations demonstrated the successful synthesis of PDCPAHPi, BPODAHPi and their hybrids. The g-C3N4protected OAHPi from external heat and thus improved the thermal stability of OAHPi. Combining g-C3N4with OAHPi contributed to reduction in peak of heat release rate, total heat release and smoke production rate of PS matrix. Reduced smoke released has also been demonstrated by smoke density chamber testing. Additionally, introduction of the hybrids led to decreased release of flammable aromatic compounds. These properties improvement could be attributed to gas phase action and physical barrier effect in condensed phase: phosphorus-containing low-energy radicals generated from OAHPi effectively captured high-energy free-radicals evolved from PS; g-C3N4nanosheets retarded the permeation of heat and the escape of volatile degradation products. Therefore, g-C3N4/OAHPi hybrids will provide a potential strategy to reduce the fire hazards of PS.
authors.affiliation: College of Environment and Resources, Fuzhou University, 2 Xueyuan Road, Fuzhou, 350002, PR China; State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, 230026, PR China. Electronic address: shiyq1986@fzu.edu.cn.
authors.forename: Yongqian
authors.initials: Y
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, 230026, PR China; Nanotechnology Centre, Institute of Textiles & Clothing, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
authors.forename: Bin
authors.initials: B
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, 230026, PR China.
authors.forename: Lijin
authors.initials: L
authors.lastname: Duan
authors.affiliation: State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, 230026, PR China.
authors.forename: Zhou
authors.initials: Z
authors.lastname: Gui
authors.affiliation: State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, 230026, PR China.
authors.forename: Bibo
authors.initials: B
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, 230026, PR China. Electronic address: yuanhu@ustc.edu.cn.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Department of Architecture and Civil Engineering, City University of Hong Kong,Tat Chee Avenue, Kowloon, Hong Kong.
authors.forename: Richard K K
authors.initials: RKK
authors.lastname: Yuen
keywords: Composites; Flame retardancy; Graphitic carbon nitride; Smoke suppression