Ultrasound assisted Synthesis of Poly (styrene-Co-methylmethacrylate)-HNT's Nanocomposites by In-Situ Emulsion Copolymerization and its Characterization

Abstract

Poly (styrene-co-methylmethacrylate)-HNT nanocomposites have been successfully synthesized by ultrasound assisted emulsion copolymerization without modification of HNT's. The key parameters that affect the stability of the emulsion and hence the properties of the resulting nanocomposites are sonication time and clay loading. The effectsof these parameters on the process were investigated in this study. Thesynthesized nanocomposites were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform and infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) to investigatemorphology and thermal stability. The embodiment of the HNTs into the copolymer matrix was confirmed by FTIR, and XRD analyses positively delineated the complete exfoliation of HNTs into the copolymer matrix on sonication for 60 min. SEM analyses revealed homogenous dispersion of HNTs into the copolymer matrix and DSC analysis showed significant improvement in glass transition temperature (Tg)of composites upto 2 weight% of HNT loading and any further loading of HNT resulted in decrease in Tg.Zeta size and zeta potential analyses confirmed the particles were in nanoscale and possessed good stability respectively. This sonochemical route of preparation proves to be a promising way to accomplish nanocomposites synthesis with insitu polymerisation and to obtain better dispersion of particles in resulting composites. � 2017 Elsevier Ltd.