Poly (styrene) latex/modified na-activated bentonite nanocomposite films: a fluorescence study

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Tarih

2008-12

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

Elsevier Science BV

Erişim Hakkı

info:eu-repo/semantics/closedAccess

Araştırma projeleri

Organizasyon Birimleri

Dergi sayısı

Özet

We studied film formation of composites of surfactant-free polystyrene (PS) nanoparticles and modified Na-activated bentonite (MLB), by steady state fluorescence (SSF) technique. The films were prepared from a mixture of pyrene (P)-labeled PS particles and MLB at various compositions at room temperature. These films were annealed at elevated temperatures above the glass transition (T(g)) temperature of polystyrene for 10 min. Scattered light (I(S)) and fluorescence intensities (I(P)) from P were measured after each annealing step to monitor the stages of film formation. Evolution of transparency of the composite films was monitored by using photon transmission intensity, I(tr) Atomic force microscopy (AFM) was used to detect the variation in physical structure of annealed composite films. The nanocomposite films exhibited a percolation threshold at 20 wt.% MLB content. Below this fraction two distinct film formation stages were observed which are known as void closure and interdiffusion and above this fraction no film formation was detected. At 0-20 wt.% MLB, minimum film formation, T(0), void closure, T(v) and healing, T(h) temperatures were determined. Void closure and interdiffusion stages were modeled and related activation energies were determined. Void closure activation energies decreased as the percent of MLB increased, no variation was observed in backbone activation energies.

Açıklama

Anahtar Kelimeler

Composite, Void closure, Interdiffusion, Fluorescence, Polystyrene latex, Bentonite, Layered silicate nanocomposites, Dtabr surfactants, Montmorillonite, Latex, Clay, Particles, Polymerization, Interdiffusion, Intercalation, Activation energy, Annealing, Carbon fiber reinforced plastics, Chemical activation, Composite materials, Electromagnetic waves, Glass transition, Latexes, Light emission, Luminescence, Nanocomposites, Nanostructured materials, Percolation (fluids), Polystyrenes, Sodium, Styrene, Surface active agents, Atomic force microscopy, Biofilm, Experimental mineralogy, Simulated annealing, Activated bentonites, Atomic forces, Elevated temperatures, Film formations, Fluorescence intensities, Fluorescence studies, Nanocomposite films, Percolation thresholds, Photon transmissions, Physical structures, Room temperatures, Scattered light, Steady state fluorescence techniques, Void closures

Kaynak

WoS Q Değeri

Q1
Q1

Scopus Q Değeri

Q1

Cilt

42

Sayı

1-2

Künye

Uğur, Ş., Yargı, Ö., Günister, E. & Pekcan, M. Ö. (2008). Poly (styrene) latex/modified na-activated bentonite nanocomposite films: A fluorescence study. Applied Clay Science, 42(1-2), 39-49. doi:10.1016/j.clay.2008.02.009