有机蒙脱土协同壳聚糖基膨胀型阻燃剂阻燃聚乳酸研究  

Synergistic effect of organic montmorillonite and chitosan-based intumescent flame retardant on flame retardant properties of polylactic acid

作　　者：黎航[1] 刘志鹏[1] 杨政[1] 凌敏[1] 张蕤[1] 

机构地区：[1]南京林业大学化学工程学院,南京210037

出　　处：《林业工程学报》2017年第4期77-83,共7页Journal of Forestry Engineering

基　　金：江苏省自然科学基金项目(BK2012821)

摘　　要：为改善聚乳酸的阻燃性能,利用植酸改性壳聚糖(PAMC)与三聚氰胺磷酸盐(MPP)复配得到一种新型膨胀型阻燃剂(IFR)体系,并将有机蒙脱土(OMMT)作为协效剂,通过熔融共混法制备阻燃聚乳酸(PLA)复合材料(PLA/PAMC/MPP/OMMT)。通过极限氧指数(LOI)、锥形燃烧量热(CONE)测试、垂直燃烧法(UL-94)和热重分析(TGA)测试分析复合材料的阻燃性能、燃烧性能和热稳定性能。采用扫描电镜(SEM)和X-射线光电子能谱(XPS)对复合材料的炭渣进行分析,研究了OMMT与PAMC/MPP在PLA复合材料中的阻燃协效作用。结果表明:与纯PLA相比,添加质量分数为25%的PAMC/MPP后,PLA2的LOI值、UL-94等级和800℃时的残炭量分别由21、NR和0.61%增至27.5、V-1级和17.28%,HRR曲线的峰值(PHRR)和总热释放量(THR)值分别由533.5 k W/m^2和81.7 MJ/m^2下降至270.2 k W/m^2和63.7 MJ/m^2。当添加质量分数为0.5%的OMMT后,PLA3的LOI值和残炭量继续增加至30.0和18.58%,PHRR和THR值进一步下降至251.6 k W/m^2和60.6 MJ/m^2,UL-94等级达到V-0级,且熔融滴落现象消失。OMMT与PAMC/MPP之间存在较好的协同效应,可有效改善PLA复合材料的阻燃性能,本研究结果可为制备绿色阻燃PLA复合材料提供理论依据。In order to improve the flame retardancy of PLA, anovel intumescent flame retardant （IFR） polylactic acid（PLA） system （PLA/PAMC/MPP/OMMT） was prepared through direct melting-blending technique. The IFRsystem was composed of phytic acid modified chitosan （PAMC） and melamine phosphate （MPP） together with or-ganic montmorillonite （OMMT） as a synergistic agent. The flammability ,burning behavior and thermal stability of thecomposites were evaluated through the limiting oxygen index （LOI）, cone calorimeter test, vertical burning test （UL-94） and thermogravimetric analysis （TGA）. The char residues of the composites were characterized by scanning elec-tron microscopy （SEM） and X-ray photoelectron spectroscopy （XPS） to investigate the synergetic effect of OMMTand PAMC/MPP on the flame retardant properties of PLA composites. After incorporation of 25 wt% of PAMC/MPP, compared with PLA1, the LOI value, UL-94 grade and the residue rate at 800℃ of PLA2 were respectivelyimproved from 21.0, no class and 0. 61 wt% to 27.5, V-1 and 17.28 wt%, and the PHRR and THR values respec-tively decreased from 533.5 kW/m2 and 81.7 MJ/m2to 270. 2 kW/m2 and 63.7 MJ/m2. Compared with PLA2,when 0. 5 wt% of PAMC/MPP were replaced by OMMT, the LOI value and the residue rate at 800~（2 of PLA3 re-spectively increased to 30. 0 and 18.58%, and the PHRR and THR values decreased to 251.6 kW/m2and 60. 6 MJ/m2. The UL-94 test could pass V-0 rating and melt-dripping phenomenon disappeared. The above results indicated thatthe synergistic flameretardant effect between OMMT and PAMC/MPP showed a satisfied synergistic effect on theflame retardant properties of the PLA composites. The results from this study could provide theoretical basis for thepreparation of green flame retardant PLA composites.

关 键 词：聚乳酸 植酸改性壳聚糖 有机蒙脱土 阻燃性能 协效 

分 类 号：TQ323.4[化学工程—合成树脂塑料工业]