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

Isitman N. A., KAYNAK C.

POLYMER DEGRADATION AND STABILITY, cilt.96, sa.12, ss.2284-2289, 2011 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 96 Sayı: 12
  • Basım Tarihi: 2011
  • Doi Numarası: 10.1016/j.polymdegradstab.2011.09.021
  • Dergi Adı: POLYMER DEGRADATION AND STABILITY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.2284-2289
  • Anahtar Kelimeler: Nanocomposite, Flammability, Montmorillonite, Flame retardant, Mechanism, STRUCTURAL-CHANGES, MIGRATION
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

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. (C) 2011 Elsevier Ltd. All rights reserved.