Carbon fibers must be protected from a high-temperature oxidizing environment because, at approximately 500 degrees C and above, the fibers exhibit reduced mass and strength stability. The fibers can be protected by the application of thermal coatings, which simultaneously improve the adhesive properties of the carbon fibers in the composite materials. Polysilazanes are a new family of heat-resistant polymer coatings that are converted into silicone carbide or silicone nitride ceramic structures at high temperatures. The converted ceramics are resistant to the effects of high temperatures. In this research work, polysilazane-based coatings were applied to carbon filament (CF) rovings with the dip-coating method. Tensile testing at room temperature and under thermal stress was carried out to assess the mechanical and thermomechanical properties of both coated and uncoated rovings. Scanning electron microscopy and energy-dispersive X-ray analysis were performed to evaluate the surface topographical properties of the coated and uncoated rovings. Thermogravimetric analysis was executed to determine the thermal stability of the polymer coatings. The coating performance on the CF rovings was determined by assessment of the test results obtained. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012