In situ Radical Copolymerization in Presence of Surface‐Modified TiO2 Nanoparticles: Influence of a Double Modification on Properties of Unsaturated Polyester (UP) Nanocomposites

In the preparation of nanocomposites, there is competition between the dispersion of nanoparticles and the formation of agglomerates. In this study, radical copolymerization of ethyl acrylate and methyl methacrylate initiated by 2,2‐azobis (isobutyro) nitrile (AIBN) was performed, in the presence of titanium oxide (TiO2) nanoparticles modified in a new approach; a good dispersion of the nanoparticles in the unsaturated polyester (UP) matrix was obtained. The TiO2 nanoparticles were exposed to 3‐(methacryloxy) propyl trimethoxy silane as the coupling agent. The presence of coupling agent‐grafted TiO2 nanoparticles in the copolymerization process resulted in the formation of a polymeric layer on the surface of the TiO2 nanoparticles (doubly modified‐TiO2). The grafting of coupling agent molecules and consequently copolymer macromolecular chains onto the surface of TiO2 nanoparticles was investigated using Fourier transform infrared (FTIR) analysis. It found that the formation of an acrylate layer on the sur...