Nanostructure of montmorillonite barrier layers: A new insight into the mechanism of flammability reduction in polymer nanocomposites

Date

2011-12-01

Author

Isitman, Nihat Ali
Kaynak, Cevdet

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This study describes the mechanism of flammability reduction in flame-retarded polymer matrix organo-montmorillonite reinforced nanocomposites. Morphologies of untested polymer nanocomposites and char residues formed by combustion in the mass loss calorimeter are characterized by XRD and TEM techniques. It is postulated that a combination of well-dispersed montmorillonite platelets and flame retardants in the polymer matrix provides nano-structured char formation. Initial montmorillonite dispersion in flame-retarded nanocomposites is found to be a major controlling factor on formed char nanostructures. An initially intercalated structure is invariantly converted to complete montmorillonite collapse whereas an initially exfoliated structure transforms to nano-structured chars demonstrating retained exfoliation or a new state of intercalation via incomplete collapse of montmorillonite layers. It is proposed that nano-structured char formation is the effective mechanism of flammability reduction, i.e. reduction in rate of heat release during combustion, in flame-retarded polymer nanocomposites.

Subject Keywords

Mechanism, Nanocomposite, Flammability, Montmorillonite, Flame retardant

URI

https://hdl.handle.net/11511/41951

Journal

POLYMER DEGRADATION AND STABILITY

DOI

https://doi.org/10.1016/j.polymdegradstab.2011.09.021

Collections

Department of Metallurgical and Materials Engineering, Article

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Citation Formats

N. A. Isitman and C. Kaynak, “Nanostructure of montmorillonite barrier layers: A new insight into the mechanism of flammability reduction in polymer nanocomposites,” POLYMER DEGRADATION AND STABILITY, pp. 2284–2289, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41951.