Steady-State Shear Viscosity of TPU

A fresh specimen prepared by injection molding at 180 °C was employed for each temperatnre. (Reprinted from Yoon, Doctoral Dissertation at the University of Akron. Copyright 2000, with permission from PU Joong Yoon.) 

Cox-Merz rule (Cox and Merz 1958) is not applicable to TPU), suggesting that the morphological state of a TPU specimen during steady-state shear flow is not the same as that during oscillatory shear flow. Similar observations were made in Chapter 8 for microphase-separated block copolymers and in Chapter 9 for TLCPs in an anisotropic state. 

Eisenbach CD, Ribbe A, Gunter C (1984). Macromol. Rapid Commun. 15 395. Fridman ID, Thomas EL (1980). Polymer 21 388. 

Hepburn C (1982). Polyurethane Elastomers, Applied Science, New York. 

Saunders JH, Frish KC (1962). Polyurethane Chemistry and Technology, Part I, Interscience, New York. 

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