The development of a process for the bioremediation of di(2-ethylhexyl) phthalate (DEHP) blended in various polymers, with a low DEHP release rate, has become an essential mission in the packaging materials industry, especially for blood-component storage materials. Hence, polypropylene and DEHP composites were prepared to evaluate their DEHP release behavior at 90 degrees C and 25 degrees C. The physical and chemical properties of the composites were evaluated with various analytical tools. Polypropylene of three different molecular weights was used to compare the different DEHP releasing rates. The incorporation and migration of DEHP significantly followed the crystalline nature of the polymer matrix. The temperature-dependent migration behavior was evaluated by UV Vis spectroscopy and LC/MS analyses. Among the three different molecular weight PP/DEHP composites, a significantly lower amount of DEHP was released from the higher molecular weight polymer composite due to its enriched crystalline nature. Moreover, the release behavior of DEHP was affected by the molecular weight and crystalline nature of PP, which can strongly hold the plasticizer, and therefore slow down its release. The high molecular weight iPP/DEHP composite may be suitable for blood-component backing materials because of its lower DEHP migration. (C) 2017 Elsevier B.V. All rights reserved.