Apparatus and methods for measuring extensional rheological properties of a material

摘要

Apparatus and methods for evaluating the rheological properties of Newtonian and non-Newtonian liquids and melts employs the principle of capillary breakup following rapid stretching of the fluid between two plates. The apparatus includes opposed surfaces defining a sample site disposed therebetween. A liquid sample undergoes an extensional deformation between the opposed surfaces which separate using a user-defined motion profile. The time profile of the diameter of the liquid filament is monitored and recorded as a function of time. Preferred embodiments of the present invention include data analysis of the diameter of the filament as a function of time which provides information regarding rheological parameters including, but not limited to, extensional viscosity versus strain.