Synthesis and characterization of polyacrylamide‐calcium carbonate and polyacrylamide‐calcium sulfate nanocomposites

Abstract Polyacrylamide‐calcium carbonate (PAM/CaCO₃) and polyacrylamide‐calcium sulfate (PAM/CaSO₄) nanocomposites were prepared via solution‐mixing technique. The resulting PAM‐based nanocomposites with various CaCO₃ and CaSO₄ nanoparticles contents (0–4% w/w) were investigated. Nanoparticles of CaCO₃ and CaSO₄ were synthesized by in situ deposition technique. In this technique, the surface modification of nanoparticles was performed by nonionic polymeric surfactant. The particle size of nanoparticles was recognized by X‐ray diffraction and scanning electron microscope (SEM) analysis which confirms that the particle has diameter of 25–33 nm. As prepared, nanocomposites films (thickness, 40‐μm) were characterized by Fourier transform infrared (FT‐IR), SEM, and energy‐dispersive X‐ray spectroscopy (EDS). FT‐IR shows the chemical structure of nanocomposites where as SEM analysis suggested that the nanofillers dispersed well in polymer matrix and EDS shows the elemental composition of the nanocomposite samples. Thermal properties of the nanocomposites were studied by using differential scanning calorimetric analysis. The PAM/CaCO₃ and PAM/CaSO₄ nanocomposites showed a higher glass transition temperature and a better thermal stability compared to the pure PAM. The glass transition temperature (T_g) of nanocomposites increases with increase in content of nanoparticles. It may be owing to the interaction between inorganic and organic components. POLYM. COMPOS.,, 2012. © 2012 Society of Plastics Engineers