title: Synthesis of highly efficient flame retardant high-density polyethylene nanocomposites with inorgano-layered double hydroxides as nanofiller using solvent mixing method.
abstract: High-density polyethylene (HDPE) polymer nanocomposites containing Zn2Al-X (X= CO3(2-), NO3(-), Cl(-), SO4(2-)) layered double hydroxide (LDH) nanoparticles with different loadings from 10 to 40 wt % were synthesized using a modified solvent mixing method. Synthesized LDH nanofillers and the corresponding nanocomposites were carefully characterized using X-ray diffraction, scanning electron microscopy, and transmission electron microscopy, etc. The thermal stability and flame retardancy behavior were investigated using a thermo gravimetric analyzer and microscale combustion calorimeter. Comparing to neat HDPE, the thermal stability of nanocomposites was significantly enhanced. With the addition of 15 wt % Zn2Al-Cl LDH, the 50% weight loss temperature was increased by 67 °C. After adding LDHs, the flame retardant performance was significantly improved as well. With 40 wt % of LDH loading, the peak heat release rate was reduced by 24%, 41%, 48%, and 54% for HDPE/Zn2Al-Cl, HDPE/Zn2Al-CO3, HDPE/Zn2Al-NO3, and HDPE/Zn2Al-SO4, respectively. We also noticed that different interlayer anions could result in different rheological properties and the influence on storage and loss moduli follows the order of SO4(2-) > NO3(-) > CO3(2-) > Cl(-). Another important finding of this work is that the influence of anions on flame retardancy follows the exact same order on rheological properties.
authors.affiliation: College of Environmental Science and Engineering, Beijing Forestry University , 35 Qinghua East Road, Haidian District, Beijing 100083, P. R. China.
authors.forename: Yanshan
authors.initials: Y
authors.lastname: Gao
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
authors.forename: Junya
authors.initials: J
authors.lastname: Wang
authors.forename: Liang
authors.initials: L
authors.lastname: Huang
authors.forename: Xingru
authors.initials: X
authors.lastname: Yan
authors.forename: Xi
authors.initials: X
authors.lastname: Zhang
authors.forename: Qingliang
authors.initials: Q
authors.lastname: He
authors.forename: Zipeng
authors.initials: Z
authors.lastname: Xing
authors.forename: Zhanhu
authors.initials: Z
authors.lastname: Guo
mesh_terms: D006358:Hot Temperature; D006878:Hydroxides / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053761:Nanocomposites / Q000737:chemistry*; D020959:Polyethylene / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D006878:Hydroxides; D020959:Polyethylene; C031356:hydroxide ion