Synthesis of hybrid organic-inorganic silicon based polymers has attracted a great interest due to the potential combination of the well-known mechanical properties of organic polymers with the attractive thermal stability of inorganic polymers. Organic polymers are formed by long carbon-carbon bonding chains with functional groups attached to them while inorganic silicon-based polymers are usually constituted of silicon in combination with elements such as nitrogen, oxygen or carbon. The aim of this work was to obtain a hybrid polymer with unique characteristics such as excellent thermal stability, low heat release rate, high heat resistance, slow burning rate without a flaming drip and limited release of toxic gases during thermal decomposition by incorporating quantities of polysilazane on polystyrene matrix by radical polymerization reaction. Bulk polymerization and solvent polymerization were chosen as methodology to obtain the product. For the polymerization, the polysilazane HTT1800 (inorganic precursor) and the organic monomer styrene were used, while dicumyl peroxide was chosen as a radical initiator. The polymerization reaction was carried out at high temperature and under argon atmosphere. A glass reactor with a condenser was used to avoid solvent loss and temperature was controlled by thermostatic bath. Subsequently, when (1-methylethyl) was used as a solvent, it was removed by vacuum distillation. Chemical and physical properties of the hybrid organic-inorganic polymer were analysed through Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Fourier Transformed Infrared (FTIR) and Flammability Analysis (in accordance with UL94).
