What Is Polymer Rheology

The rheological properties of polymeric materials vary with their chemical structures. Therefore, it is highly desirable to be able to relate the rheological properties of polymeric materials to their chemical structures. For instance, one may ask Why are the rheological properties of polystyrene so different from the rheological properties of polyethylene under an identical flow condition Unfortunately, at present there is no comprehensive molecular theory that can answer such a seemingly simple and fundamental question. 

How Does the Fluid Elasticity of Polymeric Liquids Manifest Itself in Flow  

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