A novel material was prepared through the blending of an unsaturated polyester resin/styrene mix with tung oil, which offered improved impact strength, creep resistance, modulus, and hardness. A nanoindentation technique was used to investigate the mechanical properties. With the incorporation of 1 wt % tung oil into the unsaturated polyester matrix, the impact strength, modulus, and hardness increased by 15, 20, and 41%, respectively. The impact-fractured surfaces were examined with scanning electron microscopy. The dynamic mechanical analysis was performed with a nanoindentation technique. The storage and loss modulus values were determined under cyclic loading as a function of indentation. The flexural properties also significantly increased with the incorporation of tung oil. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119:2174-2182, 2011