Synthesis and characterization of polyvinyl acetate/montmorillonite nanocomposite by in situ emulsion polymerization technique

Thermodynamic Research Laboratory, University of Kashan, Kashan, Iran; Department of Chemical Engineering, Amirkabir University of Technology, Tehran, Iran
Polymer Bulletin (Impact Factor: 1.33). 66(9):1255-1265. DOI: 10.1007/s00289-010-0399-2

ABSTRACT Exfoliated polyvinyl acetate/montmorillonite nanocomposite (PVAc/MMT) was prepared via in situ emulsion polymerization. The
resulting PVAc with various organophilic MMT contents was investigated. In the nanocomposite latex preparation, sodium lauryl
sulfate (SLS), ammonium persulfate (APS), and poly (vinyl alcohol) (PVA) are used as anionic emulsifier, conventional anionic
initiator, and stabilizer, respectively. The samples were characterized using elemental analysis, X-ray diffraction (XRD),
scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM). The XRD and AFM
results demonstrate that the MMT well dispersed at molecular level in the PVAc matrix. Thermal properties of the nanocomposite
were studied by using differential scanning calorimetric analysis (DSC). The exfoliated PVAc/MMT nanocomposite showed a higher
glass transition temperature and a better thermal stability compared to the pure PVAc.

KeywordsNanocomposite–Emulsion polymerization–Polyvinyl acetate–Montmorillonite–Exfoliation–Thermal properties

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