A study on morphological and thermal properties of polyethylene terephthalane nanocomposites containing hydrophilic and hydrophobic nanosilica

Polyethylene terephthalate (PET) based nanocomposites containing three differently modified silica particles were prepared by melt compounding. The influence of type and amount of nanosilica on various properties of nanocomposite was studied using atomic force microscope, thermal degradation, thermal-mechanical properties, scanning electron microscope, and reflectance spectra. AFM test was used to study the roughness of composites which indicated that the roughness is related to hydrophilicity degree of silica, increasing with an increase in hydrophilicity of particles. SEM images were studied on the surface, confirming that the surface roughness of nanocomposite depends on the type of nano-silica used. Results of thermal analysis showed that the interaction between nanosilica particle and polyethylene terephthalate chains is effective in thermal stability of composite. UVvis spectra of polyester nanocomposites indicated that the refraction of hydrophilic silica nanocomposites is more than hydrophobic one, indicating agglomeration of hydrophilic particles at the surface of nanocomposite compared with hydrophobic one.