AbstractIn this study, non-flammable insulator materials with high thermal resistance have been produced for vessel doors. Silica-based polymers were used as core materials. Four different synthesis routes are procured and their morphologies, thermal performances, and flammability properties are compared. Thermal properties of the synthesized silica-based polymers are improved by attaining higher porosity and surface area with different synthesizing routes. While surfactant usage provided a spherical morphology for particles, changing the drying procedure to freeze drying technique showed an increase in terms of porosity and average pore size. Amongst the synthesized silica-based polymers, the sample with the lowest thermal conductivity λ value [14 mW/(m K)] is chosen as a core material for prepared panels. After the ratio optimization of fiberglass, silicon carbide and silica-based polymer, different pressing pressures are applied to the panels. The values of 90 mW/(m K) is attained at 0.1 N/mm2 pressure and by increasing the pressing value to 0.6 N/mm2 the thermal conductivity of the panel decreases to 56 mW/(m K). Furthermore, the thermal properties of the prepared panel with the best result and commercial panels that are commonly used are also compared.