Laponite/magnetite nanoparticles including waterborne latexes and effect of conditions for stable composite latexes

Abstract

Recent studies have emphasized that the inclusion of magnetic nanoparticles (MNPs) in the polymer structure with the mini‐emulsion technique is the most ideal technique in terms of controlling their physical (size, shape, etc.) and chemical (surface chemistry, etc.) properties. In this study, MNPs were modified with clay (laponite) and made compatible with polymers. Then, clay‐modified MNPs (laponite/magnetite, LAM) were incorporated into acrylic polymers by semibatch mini‐emulsion polymerization in an oil phase containing monomer, initiator, and hydrophobic substance. The contribution of clay content to the functionality of MNPs and the properties of polymer nanoparticles containing LAM were investigated. The structures of the synthesized nanoparticles and polymeric materials were elucidated by Fourier transform infrared spectroscopy and X‐Ray Diffraction (XRD) analyses. The morphology of the latexes was clarified by atomic force microscope (AFM) and field emission scanning electron microscope (FESEM) Scanning transmission electron microscopy (STEM) analyses, and the atomic percentage values were determined by FESEM‐EDAX detector analysis. Thermal properties were determined by differential scanning calorimetry and thermogravimetric analysis, and strength endurance was determined by a tensile test. The results showed that LAM could be successfully incorporated into the polymer structure without precipitation by mini‐emulsion polymerization, and this technique is suitable for the preparation of nanocapsules. Moreover, it was determined that MNPs increased particle sizes and viscosity of the latexes. Also, increase in surface roughness with enhanced nanoparticle concentration was observed from the AFM images. The composite latex with 2% LAM showed the greatest increase in mechanical characteristics.Highlights LAM nanoparticle Synthesis was carried out. Stable nanocomposite of LAM nanoparticle in latexes was achieved via mini‐emulsion polymerization. LAM successfully incorporated to the acrylic latexes without precipitation. Properties of the acrylic latexes were improved by incorporation of LAM.