改性LDH及石墨烯片协同阻燃环氧树脂性能的研究
|
摘要
采用十二烷基苯磺酸钠(DBS)对层状双金属氢氧化物(LDH)进行改性,将改性LDH(OLDH)与石墨烯片(GNS)复配后对环氧树脂(EP)进行协同阻燃。通过X射线衍射(XRD)、傅里叶红外光谱(FTIR)分析对OLDH进行结构表征,利用热重分析仪(TGA)、锥形量热仪(CCT)、扫描电子显微镜(SEM)等对EP/OLDH-GNS复合材料的热稳定性、阻燃性能、残炭微观结构进行分析。结果表明:改性前后的LDH层间距(d)分别为0.78和1.32 nm,说明DBS进入LDH层间进行离子交换。EP/OLDH-GNS复合材料在700℃时的残炭率明显高于纯EP,说明OLDH与GNS的加入有利于环氧固化物形成致密炭层。CCT及残炭SEM分析显示,随着OLDH、GNS添加量的增加,复合材料的最大热释放速率逐渐降低,所形成的炭层能够阻隔氧气和热量的传递,起到延缓材料燃烧的作用;OLDH、GNS具有明显的协效阻燃作用。
The layered double hydroxide(LDH) was modified with sodium dodecylbenzene sulfonate(DBS), then the modified LDH(OLDH) and graphene sheets(GNS) were combined, and served as flame retardant in epoxy resin(EP). The structure of OLDH was characterized by X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FTIR). The thermal stability, flame retardant properties and microstructure of carbon residue of EP/OLDH-GNS composites were observed using thermogravimetric analysis(TGA), cone calorimeter(CCT) and scanning electron microscopy(SEM). The results show that, the LDH layer spacing(d) before and after modification are 0.78 and 1.32 nm, respectively. It indicates that DBS has entered the LDH layer for ion exchange. The carbon residue rate of the EP/OLDH-GNS composite at 700℃ is significantly higher than that of pure EP. OLDH and GNS is beneficial to the formation of a dense carbon layer of the cured EP product. The test results of CCT and carbon residue show that, the maximum heat release rate of flame retardant epoxy composite decreased gradually with the increasing amount of OLDH and GNS. The carbon layer can block oxygen and heat, and delay the combustion of EP. Moreover, the synergistic effect of flame retardant is obvious.
The layered double hydroxide(LDH) was modified with sodium dodecylbenzene sulfonate(DBS), then the modified LDH(OLDH) and graphene sheets(GNS) were combined, and served as flame retardant in epoxy resin(EP). The structure of OLDH was characterized by X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FTIR). The thermal stability, flame retardant properties and microstructure of carbon residue of EP/OLDH-GNS composites were observed using thermogravimetric analysis(TGA), cone calorimeter(CCT) and scanning electron microscopy(SEM). The results show that, the LDH layer spacing(d) before and after modification are 0.78 and 1.32 nm, respectively. It indicates that DBS has entered the LDH layer for ion exchange. The carbon residue rate of the EP/OLDH-GNS composite at 700℃ is significantly higher than that of pure EP. OLDH and GNS is beneficial to the formation of a dense carbon layer of the cured EP product. The test results of CCT and carbon residue show that, the maximum heat release rate of flame retardant epoxy composite decreased gradually with the increasing amount of OLDH and GNS. The carbon layer can block oxygen and heat, and delay the combustion of EP. Moreover, the synergistic effect of flame retardant is obvious.
引文
[1]朱继伟,胡泊,武保林,等.含磷阻燃剂在环氧树脂中的应用[J].塑料科技,2019,47(2):81-85.
[2]严伟,李乾波,杨春林,等.1-芘丁酸改性石墨烯片对环氧树脂阻燃性能的影响[J].塑料科技,2018,46(10):31-35.
[3]严伟,李乾波,杨春林,等.DOPO改性ATH阻燃环氧树脂性能的研究[J].塑料工业,2018,46(8):119-123.
[4]Sun F,Yu T,Hu C Q,et al.Influence of functionalized graphene by grafted phosphorus containing flame retardant on the flammability of carbon fiber/epoxy resin(CF/ER)composite[J].Composites Science and Technology,2016,136:76-84.
[5]Yuan B H,Sun Y R,Chen X F,et al.Poorly-/well-dispersed graphene:Abnormal influence on flammability and fire behavior of intumescent flame retardant[J].Composites Part A:Applied Science and Manufacturing,2018,109:345-354.
[6]Liu S,Fang Z P,Yan H Q,et al.Superior flame retardancy of epoxy resin by the combined addition of graphene nanosheets and DOPO[J].RSC Advances,2016,6:5 288-5 295.
[7]Yan W,Zhang M Q,Yu J,et al.Synergistic flame-retardant effect of epoxy resin combined with phenethyl-bridged DOPO derivative and graphene nanosheets[J].Chinese Journal of Polymer Science,2019,37:79-88.
[8]Zuo L Z,Fan W,Zhang Y F,et al.Graphene/montmorillonite hybrid synergistically reinforced polyimide composite aerogels with enhanced flame-retardant performance[J].Composites Science and Technology,2017,139:57-63.
[9]陈博,李向梅,欧育湘,等.纳米层状双羟基化合物阻燃聚合物研究进展[J].中国塑料,2015,29(1):1-5.
[10]Kalali E N,Wang Xin,Wang D Y.Functionalized layered double hydroxide-based epoxy nanocomposites with improved flame retardancy and mechanical properties[J].Journal of Materials Chemistry A,2015,3:6 819-6 826.
[11]Gao Y S,Wang Q,Wang J Y,et al.Synthesis of highly efficient flame retardant high-density polyethylene nanocomposites with inorgano-layered double hydroxides as nanofiller using solvent mixing method[J].ACS Applied Materials&Interfaces,2014,6:5 094-5 104.
[12]Kaul P K,Samson A J,Selvan G T,et al.Synergistic effect of LDH in the presence of organophosphate on thermal and flammable properties of an epoxy nanocomposite[J].Applied Clay Science,2017,135:134-143.
[13]Cai J,Heng H M,Hu X P,et al.A facile method for the preparation of novel fire-retardant layered double hydroxide and its application as nanofiller in UP[J].Polymer Degradation and Stability,2016,126:47-57.
[2]严伟,李乾波,杨春林,等.1-芘丁酸改性石墨烯片对环氧树脂阻燃性能的影响[J].塑料科技,2018,46(10):31-35.
[3]严伟,李乾波,杨春林,等.DOPO改性ATH阻燃环氧树脂性能的研究[J].塑料工业,2018,46(8):119-123.
[4]Sun F,Yu T,Hu C Q,et al.Influence of functionalized graphene by grafted phosphorus containing flame retardant on the flammability of carbon fiber/epoxy resin(CF/ER)composite[J].Composites Science and Technology,2016,136:76-84.
[5]Yuan B H,Sun Y R,Chen X F,et al.Poorly-/well-dispersed graphene:Abnormal influence on flammability and fire behavior of intumescent flame retardant[J].Composites Part A:Applied Science and Manufacturing,2018,109:345-354.
[6]Liu S,Fang Z P,Yan H Q,et al.Superior flame retardancy of epoxy resin by the combined addition of graphene nanosheets and DOPO[J].RSC Advances,2016,6:5 288-5 295.
[7]Yan W,Zhang M Q,Yu J,et al.Synergistic flame-retardant effect of epoxy resin combined with phenethyl-bridged DOPO derivative and graphene nanosheets[J].Chinese Journal of Polymer Science,2019,37:79-88.
[8]Zuo L Z,Fan W,Zhang Y F,et al.Graphene/montmorillonite hybrid synergistically reinforced polyimide composite aerogels with enhanced flame-retardant performance[J].Composites Science and Technology,2017,139:57-63.
[9]陈博,李向梅,欧育湘,等.纳米层状双羟基化合物阻燃聚合物研究进展[J].中国塑料,2015,29(1):1-5.
[10]Kalali E N,Wang Xin,Wang D Y.Functionalized layered double hydroxide-based epoxy nanocomposites with improved flame retardancy and mechanical properties[J].Journal of Materials Chemistry A,2015,3:6 819-6 826.
[11]Gao Y S,Wang Q,Wang J Y,et al.Synthesis of highly efficient flame retardant high-density polyethylene nanocomposites with inorgano-layered double hydroxides as nanofiller using solvent mixing method[J].ACS Applied Materials&Interfaces,2014,6:5 094-5 104.
[12]Kaul P K,Samson A J,Selvan G T,et al.Synergistic effect of LDH in the presence of organophosphate on thermal and flammable properties of an epoxy nanocomposite[J].Applied Clay Science,2017,135:134-143.
[13]Cai J,Heng H M,Hu X P,et al.A facile method for the preparation of novel fire-retardant layered double hydroxide and its application as nanofiller in UP[J].Polymer Degradation and Stability,2016,126:47-57.