Extensional Flow of Bulk Polymers
نویسنده
چکیده
A standard Instron testing machine, in which crosshead displacement varies linearly with time was modified so that crosshead displacement varies exponentially with time. This change permits testing at constant Hencky strain rate (c = fi/8), which provides a constant stretch history for both simple extensional flow and strip biaxial extensional flow. This results in a visualization of the steady flow for both types of deformation and enables one to derive the non-Newtonian viscosity from the steady-state region.
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