Pyrolysis properties of exfoliated nanocomposite synthesized by vinyl acetate and organic montmorillonite through different processes

Thermogravimetric analysis is always used to study the pyrolysis process of polymers and composites and can reflect their thermal degradation properties. In the article, an exfoliated nanocomposite was synthesized by vinyl acetate and organic montmorillonite through different processes. Linear macromolecular chains of polyvinyl acetate were formed in the layers of organic montmorillonite, and no chemical bond existed between them, but only physical effect. Organic montmorillonite was exfoliated into layers or sheets of nanoparticles, randomly dispersing in the matrix of polyvinyl acetate, so the different synthesis processes and the addition of organic montmorillonite had little effect on the structure of the exfoliated nanocomposite, but some certain effect on the pyrolysis properties. The pyrolysis was found to consist of eight phases, and those of polyvinyl acetate and the exfoliated nanocomposite were similar. The presence of organic montmorillonite had no obvious effect on the pyrolysis temperature, but mainly delayed the thermal degradation process. In addition, their pyrolysis kinetics was firstly analyzed by the Agrawal integral equation. The kinetic parameters, including the kinetics mechanism function, the activation energy, the frequency factor, the reaction order, the reaction rate constant, the form factor of heat flow curve, and the kinetic compensation effect equation, were obtained in detail.