Paper Number
PO26 

Session
Poster Session

Title
Decomposing tensile stress during startup uniaxial extension of entangled melts

Presentation Date and Time
October 8, 2014 (Wednesday) 6:05

Track / Room
Poster Session / Poster

Authors (Click on name to view author profile)

1. Lin, Panpan (University of Akron, Polymer Science)
2. Wang, Shi-Qing (University of Akron)

Author and Affiliation Lines (in printed abstract book)
Panpan Lin and Shi-Qing Wang
University of Akron, Akron, OH

Speaker / Presenter 
Lin, Panpan

Text of Abstract
Upon startup uniaxial extension, entangled melts undergo global yielding, characterized by the emergence of a maximum in the engineering stress (Wang and Wang 2008). In this work, we carry out in situ temperature measurements of extending SBR melts by an IR imaging camera. Such observations of heat release not only provide more information about the nature of the stress response but also help us demonstrate the various types of specimen breakup (Zhu and Wang 2013) during continuous extension. Depending on the applied Hencky rate and the stage of the extension, we show that either elastic (entropic) or viscous (dissipative, frictional) component of the tensile stress can dominant. Wang, Y. Y., and Wang, S. Q., ‘‘From elastic deformation to terminal flow of a monodisperse entangled melt in uniaxial extension,’’ Journal of Rheology 52, 1275-1290 (2008). Zhu, X., and Wang, S.-Q., ‘‘Mechanisms for different failure modes in startup uniaxial extension: Tensile (rupture-like) failure and necking,’’ Journal of Rheology 57, 223-248 (2013).