Rheology Lab

Catalog description

This lab is designed to provide a practical and theoretical understanding of the rheologcal behaviors of thermoplastic polymers, curing kinetics of chemical and physical crosslink polymers, as well as the crystallization kinetics of semi-crystalline polymers. Evaluation and characterization of phase separation in binary miscible polymer blends and order-disorder transition in block copolymer will be studied rheologically for different blends and block copolymers, respectively. In addition, the students will learn the practical and fundamental aspects of rheology in the linear and non-linear viscoelastic regimes under wide range of temperature, shear rate, and strain amplitude. Student will be trained to operate, calibrate and maintain a number of rheometers, such as rotational rheometer and capillary rheometer. Selection of the right geometry (e.g. parallel plate, cone-plate, concentric cylinders, rectangular torsion, three-point bending, etc.) for specific rheological measurements is very crucial and will have significant effect on the accuracy of the data. The selection of geometry is also related to the different states of the material (e.g. solid, liquid, and gel). The advantages and disadvantages or limitation of each geometry will be studied. Analysis and theoretical fitting to the experimental data will be an essential part of this lab course. Several rheological principles and models will be studied in this course, such as WLF or Time-Temperature Superposition Principle, Cox-Merz Rule, classical theories of Maxwell, Rouse, and Doi-Edwards as well as Cross, Carreau-Yasuda, and Palierne models.