The essence of nonlinear polymer rheology: everything you must know
by Shi-Qing Wang, University of Akron, USA
Polymer processing suffers from a variety of rate-limiting difficulties. In extrusion alone, we encounter surface roughness on extrudate (sharkskin), quasi-periodic extrudate distortion associated with pressure oscillation and gross melt fracture. To have better mechanical characteristics, polyolefin resins need to have sufficiently high molecular weight, and the same is true for rubbers. Consequently, useful polymers, in the annual amount of one hundred million tons, are always strongly entangled. Most of the melt processing instabilities of these polyolefin and rubbers are due to the presence of high entanglement. Our task is to understand and predict rheological responses of entangled polymeric materials.
This presentation summarizes more than one decade of intensive research carried out at Akron that has completely changed our worldview of the essence of nonlinear rheology of entangled polymers. Continue reading “iRTG lecture series by Shi-Qing Wang (October 14, 2019) | part 1”
