Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, School of Environmental Science and Safety Engineering, Tianjin University of Technology, 391 Binshui Xidao, Xiqing District, Tianjin 300384, China.
School of Chemical Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang, Malaysia.
Int J Biol Macromol. 2024 Jun;271(Pt 1):132610. doi: 10.1016/j.ijbiomac.2024.132610. Epub 2024 May 23.
The flammability of bio-derived poly(L-lactic acid) (PLA) greatly limits its application and eco-friendly multifunctional fire-fighting PLA-based composites are highly desired. In this work, a fully bio-based modified CS (C-CS) and commercially available eco-friendly ammonium polyphosphate (APP) were used as a synergistic flame retardant agent (C-CS/APP) to investigate its effects on fire-proofing performance and diverse properties of the PLA. The PLA/5%C-CS/5%APP composite exhibited excellent fire-resistant performance with anti-droplet, smoke-suppression and self-extinguishing property, and its limited oxygen index enhanced by 37 % (compared with neat PLA). This composite reached the highest V-0 fire safety rating, and its peak of heat release rate and total smoke production reduced by 26.5 % and 68.3 %, respectively. In addition, the char residue yield after the cone calorimeter test increased by 46 times in the composite, indicating an outstanding char-forming capacity. The condensed phase flame retardancy played a crucial role on the fire-fighting of this composite, that is, significantly enhanced char residue (as a physical barrier) blocked the heat exchange and O entry, and further suppressed the combustion reaction. Additionally, the PLA-based composite showed outstanding UV-absorption property, good anti-bacterial effect, and increased hydrophilicity and crystallizability.
生物衍生聚 L-乳酸（PLA）的可燃性极大地限制了其应用，因此人们非常希望制备具有环境友好多功能的阻燃 PLA 基复合材料。在这项工作中，我们使用了完全生物基改性壳聚糖（C-CS）和市售的环保型聚磷酸铵（APP）作为协同阻燃剂（C-CS/APP），研究了其对 PLA 防火性能和多种性能的影响。结果表明，添加 5%C-CS/5%APP 的 PLA 复合材料具有优异的阻燃性能，表现出抗滴落、抑烟和自熄特性，其极限氧指数提高了 37%（与纯 PLA 相比）。该复合材料达到了最高的 V-0 消防安全等级，其热释放率峰值和总烟雾产生量分别降低了 26.5%和 68.3%。此外，在锥形量热仪测试后，复合材料的炭残留量增加了 46 倍，表明其具有出色的成炭能力。凝聚相阻燃在该复合材料的阻燃中起着至关重要的作用，即显著增强的炭残留物（作为物理屏障）阻止了热量交换和 O2 的进入，进一步抑制了燃烧反应。此外，基于 PLA 的复合材料还表现出优异的紫外吸收性能、良好的抗菌效果、提高的亲水性和结晶性。
