Study On Flame-Retarded Property Of Unsaturated Polyester/Montmorillonite Nanocomposite And Flame-Retarded Synergetic Effect Of Montmorillonite

Polymer layered-silicate(PLS) nanocomposites not only enhance mechanical properties,gas barrier properties,solvent resistance and thermal stability of the matrix,but also improve the flame retardant properties compared to conventional filled polymers. PLS nanocomposites have distinct advantages over conventional fire retardants in terms of low level of loading,high flame retardant efficiency and enviremental friendly and so on. In addition,PLS nanocomposites do not deteriorate the general properties.The organic montmorillonite is prepared successfully by adopting cation interchange after the choice of suitable intercalation agent. The result of modification and the state of intercalation of organic cation are characterized by means of FT-IR and XRD. After the organic modification of montmorillonite, the interplanar spacing of montmorillonite increased from 1.21nm to 1.78nm.UP(unsaturated polyester)\OMMT(montmorillonite) nanocomposites were prepared by dispersing organically modified montmorillonite in prepromoted UP resin and subsequently cross-linked using methyl ethyl ketone peroxide catalyst at several different clay concentrations. X-ray diffraction studies revealed the formation of intercalation nanocomposite with the change of the peak corresponding to the basal spacing of the pure OMMT. Transmission electron microscopy was used to study the morphology and showed the nanocomposite to be comprised of intercalated aggregates throughout the matrix.The mechanical properties and flammability of flame retardant nanocomposites were investigated by tensile impact and LOI experiments. Compared to pure UP that the LOI of nanocomposites with 0.5wt% organic montmorillonite increased by 2.2 from 22 to 24.2. The tensile strength and impact strength of nanocomposites increased by 8.76% and 68.65% respectively. Compared to traditional DBDPO/UP composites of same retardant grad,The tensile strength and impact strength of nanocomposites increased by 8.76% and 68.65% respectively. The flame retardant mechanisms of nanocomposites are discussed based on the flammability parameters analyses and the burnt residues.DBDPO/UP/OMMT nanocomposites was prepared by in situ intercalate on polymerization. Its microstructure was characterized by XRD,SEM and TEM. The mechanical properties and flammability of flame retardant nanocomposites were investigated by tensile impact and LOI experiments. Compared to tradition DBDPO/Up composites that the LOI of nanocomposites with 0.6wt% organic montmorillonite increased by 1.3 from 24.1 to 25. 4.The impact strength and tensile strength of nanocomposites increased by 82.66% and 31.05% respectively. Digital Photographs and SEM micrographs of the residues after combustion showed that the char of nanocomposites are more compact than the pure UP...