The development of poly(lactic acid) (PLA) composites having flame retardancy, tensile toughness and transparency is the state-of-the-art, which requires meticulous selection and combination of additives. To achieve this goal, an ionic liquid (IL) tetrabutylphosphonium tetrafluoroborate is synthesized and used as a synergist for ammonium polyphosphate (APP). Due to the high synergistic effect between them, only 1.5 wt% IL and 1.5 wt% APP (total amount of 3 wt%) can endow PLA with fire safety, i.e. limiting oxygen index (LOI) of 27.2, UL 94 V-0 rating and low heat release rate of 290 kW m⁻². Besides, the elongation at break of PLA containing 3 wt% IL/APP increases from 8.5% of PLA to 204.6%. Meanwhile, the incorporation of IL/APP has tiny impact on the transparency of PLA. The PLA/IL/APP possessing toughness and flame retardancy shows great potentials in the fields of packaging, automotive and electronic and electric industry in the future.

具有阻燃性，拉伸韧性和透明性的聚乳酸（PLA）复合材料的开发是最新技术，其需要精心选择和组合添加剂。为实现此目标，合成了离子液体（IL）四氟硼酸四丁基phosph，并用作多磷酸铵（APP）的增效剂。由于它们之间的高协同作用，只有1.5 wt％的IL和1.5 wt％的APP（总量为3 wt％）才能使PLA具有防火安全性，即极限氧指数（LOI）为27.2，UL 94 V-0等级290 kW m ^{− 2的}低放热率。另外，含有3wt％IL / APP的PLA的断裂伸长率从8.5％的PLA增加到204.6％。同时，IL / APP的加入对PLA的透明度影响很小。具有韧性和阻燃性的PLA / IL / APP未来在包装，汽车，电子和电气工业领域显示出巨大的潜力。