S. D. Jiang, Z. M. Bai, G. Tang, L. Song, A. A. Stec, T. R. Hull, Y. Hu and W. Z. Hu (2014) Synthesis of Mesoporous Silica@Co-Al Layered Double Hydroxide Spheres: Layer-by-Layer Method and Their Effects on the Flame Retardancy of Epoxy Resins. Journal/Acs Applied Materials & Interfaces 6 14076-14086. [In English]
Web link: http://dx.doi.org/10.1021/am503412y
Keywords: mesoporous silica@Co-Al layered double hydroxide spheres; layer-by-layer; method; polymer composites; thermal stability; flame retardancy; mechanism; CARBON NANOTUBES; MANGANESE OXIDE; NANOCOMPOSITES; MICROSPHERES; CATALYST; SHELL; NANOPARTICLES; FLAMMABILITY; DELAMINATION; NANOSPHERES

Abstract: Hierarchical mesoporous silica@Co-Al layered double hydroxide (m-SiO2@Co-Al LDH) spheres were prepared through a layer-by-layer assembly process, in order to integrate their excellent physical and chemical functionalities. TEM results depicted that, due to the electrostatic potential difference between m-SiO2 and Co-Al LDH, the synthetic m-SiO2@Co-Al LDH hybrids exhibited that m-SiO2 spheres were packaged by the Co-Al LDH nanosheets. Subsequently, the m-SiO2@Co-Al LDH spheres were incorporated into epoxy resin (EP) to prepare specimens for investigation of their flame-retardant performance. Cone results indicated that m-SiO2@Co-Al LDH incorporated obviously improved fire retardant of EP. A plausible mechanism of fire retardant was hypothesized based on the analyses of thermal conductivity, char residues, and pyrolysis fragments. Labyrinth effect of m-SiO2 and formation of graphitized carbon char catalyzed by Co-Al LDH play pivotal roles in the flame retardance enhancement.