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Rheological responses under elongational flow at non-isothermal condition are significantly important for actual polymer processing. Drawdown force, defined as a force required to stretch a molten polymer, was evaluated as the non-isothermal rheological response using polypropylene (PP) in this study. It was found that the die length affected the drawdown force, which was pronounced for a system having a long relaxation time. The prompt crystallization after passing through a long die would be responsible for this phenomenon. Furthermore, the addition of a nucleating agent was quite effective to increase the drawdown force, at which the shape of a nucleating agent has to be considered. The accelerated crystallization by the addition of a fibrous nucleating agent resulted in the pseudo shish-kebab structure, leading to high modulus in the flow direction. Finally, the addition of a low-viscous acrylate polymer was found to enhance the drawdown force of PP. Due to the prompt solidification of the acrylate polymer under a rapid cooling condition, the dispersions acted as rigid fibers before the crystallization of PP. These modification methods will be available to improve the processability at various processing operations at which a molten polymer is stretched at non-isothermal condition. [ABSTRACT FROM AUTHOR]