writer：Jing J, Zhang Y, Tang XL, Fang, ZP*
keywords：flame retardant, diphenolic acid, polylactic acid
source：期刊
specific source：RSC Advances, 2016.5, 6, 49019-49027
Issue time：2016年
Organophosphorus compound as one of the most preferred flame retardants is traditionally derived from petroleum resources. Of recent interest is the exploration of renewable candidates as the precursors to synthesis these compounds. Here, we report the synthesis of a novel bio-based polyphosphonate (BPPT) through the reaction of plant-derived diphenolic acid (DPA), caged bicyclic phosphorus (PEPA) and phenylphosphonic dichloride (PPDC) in two steps. The BPPT was used as flame retardant to prepare polylactic acid (PLA) blends. Significant enhancement in the limiting oxygen index of PLA (28.8, 33.7 and 35.4 with 2 wt%, 4 wt%, and 6 wt% of BPPT, respectively, in the PLA blends) was obtained. Additionally, the results in the UL94 flammability tests demonstrates that BPPT is effective to quench the flame, which facilitate PLA blends to achieve V0 level at BPPT loading of 4 wt%. The data of the cone tests confirm that gas phase mechanism is mainly responsible for the excellent flame retardancy. The flame retardant PLA blends developed herein contains a bio-mass content of more than 95 wt%.