ABSTRACTPolystyrene (PS) is one of the commonly used polymer in food packaging, that is why it generates a large amount of residual PS: because of the need of reduce environmental damage that occurs, it is common to recycle this polymer. Recycling of PS may be affected by the introduction of biodegradable polymer in industrial food. For this reason we have studied the influence that generates small amounts of biodegradable polymer (PLA, PHB, and TPS) in the recycled PS properties. The recycled PS and biodegradable polymers blends were evaluated by measuring the Vicat softening temperature, melt flow index, Fourier transformed infrared spectroscopy, and mechanical properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41161.