DOPS衍生物阻燃剂的合成及聚乳酸复合材料的性能（急）

Synthesis of flame retardant Based on DOPS Derivatives and properties of polylactic acid composites

摘要:

以马来酸酐(MAH)和9，10-二氢-9-氧杂-10-磷杂菲-10-硫化物(DOPS)为原料，合成马来酸酐-9，10-二氢-9-氧杂-10-磷杂菲-10-硫化物(MAH-DOPS)，并将MAH-DOPS应用于聚乳酸(PLA)的阻燃改性。采用热重分析(TG)、极限氧指数(LOI)、垂直燃烧(UL-94)、锥形量热(CONE)、热重-红外光谱联用(TG-FTIR)和扫描电镜-X射线能量色谱(SEM-EDS)等研究了MAH-DOPS对PLA的热稳定性、阻燃性能、力学性能和热降解行为的影响。实验结果表明，阻燃剂MAH-DOPS中的P、S元素产生了协同阻燃作用，提高了阻燃效率，改善了PLA的阻燃性能。当阻燃剂的添加量为5%时，PLA/MAH-DOPS阻燃复合材料的LOI值为28.1%，垂直燃烧等级达到UL-94 V-0级，总热释放量(THR)和平均有效燃烧热(Av-EHC)降低了。从阻燃机理看，MAH-DOPS通过抑制火焰和成炭分别在气相和凝聚相发挥阻燃作用，并以气相阻燃机理为主。

Abstract:

A novel phosphaphenanthrene derivative, MAH-DOPS was synthesized with DOPS and maleic anhydride (MAH), and it was added into polylactic acid(PLA) to form a series of PLA/MAH-DOPS composites by melt blending. The structure of MAH-DOPS was characterized by Fourier infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR) and high resolution mass spectrometry (HR MS). The thermal stabilities, flame-retardant, mechanical properties and thermal degradation behaviour of MAH-DOPS on PLA are investigated by TG, LOI, UL-94, CONE, TG-FTIR and SEM-EDS. The results show that the P and S elements in the flame retardant MAH-DOPS exert a synergistic flame retardant effect, increasing the flame retardant efficiency and improving the flame retardant properties of PLA. At flame-retardant content of 5 wt% (P 0.47%)，the initial decomposition temperature(T5%) of PLA/MAH-DOPS is 315.4℃, which is lower than that of PLA(332.5℃）, the char residue is increased，the LOI value of PLA/MAH-DOPS is 28.6% , the vertical combustion grade is UL-94 V-0, both of THR and Av-EHC of PLA/MAH-DOPS were decreased.The?mechanical?properties results show that compared with pure PLA, the bending strength of PLA/MAH-DOPS increases by 2.66%, while the tensile strength and notch impact strength decreases slightly. MAH-DOPS exert a flame retardant effect in the gas phase and condensed phase by flame suppression and carbon formation respectively, and the gas phase flame retardant mechanism mainly.