Synthesis of nanoparticles and preparation and characterization of nanopolymer matrix composites

In this study, nano α-alumina particles were synthesized by a sol–gel method using aqueous solutions of aluminum isopropoxide and 0.5?M aluminum nitrate. 1/3-benzene disoulfonic acid disodium salt (SDBS) and fluoride were used as surfactant stabilizing agent and additive, respectively. Results indicated that the finest size for nonagglomerated nanoalumina particles (15–20?nm) was achieved at 950?°C. The next part was about preparing PP nanocomposite containing nano α-Al₂O₃ particles. Mechanical tests, such as tensile, flexural, and impact tests showed that mechanical properties of the composite were enhanced by addition of nano α-Al₂O₃ particles and dispersant to the polymer. However, higher concentration of nano α-Al₂O₃ loading resulted in reduction of those mechanical properties, which could be due to agglomeration of nano α-Al₂O₃ particles. Transmission and scanning electron microscopic observations of the nanocomposites also showed that fracture surface became more roughened by increasing the content of filler loading from 1 to 4% wt.