Sodium montmorillonite modified with methacryloxy and vinylsilanes: Influence of silylation on the morphology of clay/unsaturated polyester nanocomposites

Unsaturated polyester resins are widely used in the automotive, construction and naval industries. To further widen their application, they may be combined with clay minerals, which are advantageous due to their thermal, barrier, inflammability and stiffness characteristics. In order to avoid agglomeration and improve the interaction of Cloisite® Na+ montmorillonite (Mt) with an unsaturated polyester matrix, this study focused on clay minerals modified with compatible silanes, vinyltriethoxysilane (VTES) and γ-methacryloxypropyltrimethoxysilane (MPS), and their use in composites in comparison with nanocomposites prepared using commercial clays (Cloisite® 30B and Cloisite® 15A). Functionalization of Cloisite®Na with MPS and VTES was confirmed by the appearance of characteristic infrared bands and the increase in the basal spacing. The nanocomposites containing silane-modified clays prepared in hydro-alcoholic solution showed the best result compared with ethanol solution. The presence of iron changed the color of the CNa and C30B samples and all of those prepared with silane modified Na-Mt-clays.