Studies Of Halogen-free Intumescent Flame Retardant In Polylactide (PLA)

Based on the environmental characteristics of poly lactic acid (PLA), the flame retardant added in PLA must be green and pollution-free.In recent years, the halogen-free intumescent flame retardant gradually becomes a research hotspot, and due to its low smoke, halogen-free, non-toxic environmental properties, it is very suitable forPLA.At present, the flame retardant effect of the traditional intumescent flame retardant system (APP/PER) added in PLA is not ideal, and the serious dripping phenomenon of PLA in combustion process is not effective improved. So,searching the effective intumescent flame retardant applied in PLA is particularly important.Firstly, this article used THEIC as the charring agent joined with the APP to flame retardant PLA, and preliminary studiedthe flame retardant effect of THEIC on PLA.Then TT23 and TT4 charring agents were synthesized by THEIC andTPA, and these two charring agents were also added in PLA. From the experimental results, as the total weight of APP and TT4 at 30%, the ratio of 5:1,the effect flame retardant PLA was best. At this formulation, the dripping phenomenon of PLA during combustion got obvious improvement, and UL-94 test could achieve V-Olevel, the LOI value was as high as 40.6 at the same time, and material thermal stability has been significantly increasing. Secondly, in order to reduce the amount of adding flame retardant and improve the material mechanical properties, this paper introduced the glass fiber (GF) and starch (ST) as synergistic agent added in PLA.Experiments prove that the TT4 synthesized by ourselves in this article is successfully applied in flame retardant PLA as charring agent, and at the same time introducing the synergistic agent provides an effective new wayto improve the PLA’s mechanical properties.