Ceramer Coatings from Castor Oil or Epoxidized Castor Oil and Tetraethoxysilane

New inorganic‐organic hybrids were synthesized through the reaction of castor oil (CO) or epoxidized castor oil (ECO) with tetraethoxysilane (TEOS). The mass proportions of ECO/TEOS varied from 90∶10 to 60∶40, and films of the material were thermally cured. An IR spectroscopy analysis was performed, and macro‐ and microscopic properties such as adhesion, hardness, swelling in toluene, microstructure (scanning electron microscopy), and Tg were investigated as a function of the proportion of their inorganic‐organic precursor. Morphologic studies showed that the hybrid films were homogeneous when lower proportions of the inorganic precursors were used. Hardness and tensile strength increased with TEOS concentration, whereas swelling in toluene decreased with TEOS concentration. Good adhesion was observed throughout the hybrid series.