Fabrication of ZrP nanosheet decorated macromolecular charring agent and its efficient synergism with ammonium polyphosphate in flame-retarding polypropylene. (February 2018)

• Record Type: Journal Article
• Authors: Xie, Huali; Lai, Xuejun; Li, Hongqiang; Zeng, Xingrong
• Is Part Of: Composites. Volume 105(2018)
• Page Start: 223
• Page End: 234
• Publication Date: 2018-02
• Subjects: A. Nanocomposites -- B. Flame/fire retardancy -- B. Thermal properties -- D. Thermal analysis; Composite materials -- Periodicals; Manufacturing processes -- Periodicals; Composite materials; Manufacturing processes; Periodicals; 620.11805
• DOI: 10.1016/j.compositesa.2017.12.001
• Languages: English
• ISSNs: 1359-835X

Abstract

Abstract: Poor efficiency is one of the biggest challenges for halogen-free flame retardant polymer. Catalyzing the carbonization of polymer itself during combustion is proposed to be a promising way to address this issue. In this work, a novel macromolecular charring agent (MCA) decorated by zirconium phosphate nanosheet named ZrP-d-MCA was synthesized and characterized. Subsequently, it was combined with ammonium polyphosphate (APP) to reduce the flammability of polypropylene (PP). When the contents of ZrP-d-MCA and APP were 5 wt% and 15 wt%, respectively, PP/Zr-d-MCA/APP could reach a limiting oxygen index of 32.5% and achieve UL-94 V-0 rating. Moreover, the bench-scale combustion performance determined by the cone calorimeter was significantly improved. The flame-retardant mechanism of ZrP-d-MCA/APP was revealed: during combustion, ZrP nanosheet could efficiently catalyze the charring reactions of MCA to form closed micro-nano char-cages, in which the degradation products of PP would be trapped and catalyzed into thermostable graphitization char.