Preceramic polymer zirconoborosiloxane was synthesized from the reaction with boric acid, diphenyldiethoxysilane and zirconium (IV) propoxide via solventless process. The thermogravimetric analysis of the polymer showed that ceramic yield as decomposition product at 900 degrees C was 71%. The pyrolysis of zirconoborosiloxane in an argon gas environment was investigated as standard pyrolytic process up to 1650 degrees C. Microstructure evolution of ceramic phases was made by means of Fourier transform infrared, Raman spectroscopy, X-ray diffraction and scanning electron microscope analysis. The results clearly demonstrated the pyrolysis products at 1650 degrees C consist of totally non-oxide ceramic phases beta-SIC, ZrB2 and free carbon. (C) 2017 Elsevier B.V. All rights reserved.