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Flow Visualization of Polymer Processing Additive Effects



Kalman D. Migler, C Lavallee, M P. Dillon, S S. Woods, C L. Gettinger


Flow visualization was used to understand how polymer-processing additives (PPA) eliminate sharkskin in linear low-density polyethylene (LLDPE). A sapphire capillary die was used to image the coating of the PPA onto the die wall. Depth resolved optical microscopy was used to measure the velocity profiles. When added, the PPA migrates to and coats the die wall, induces slippage, and eliminates sharkskin. The interface between the PPA and LLDPE is characterized by long stripes in the flow direction.
Proceedings Title
Society of Plastics Engineers, Conference | 59 | | Society of Plastic Engineers
No. 1
Conference Dates
May 6-10, 2001
Conference Location
Dallas, TX
Conference Title
ANTEC (Society of Plastics Engineers. Technical Conference)


extrusion, instabilities, polyethylene, rheology, sharkskin, velocimetry


Migler, K. , Lavallee, C. , Dillon, M. , Woods, S. and Gettinger, C. (2001), Flow Visualization of Polymer Processing Additive Effects, Society of Plastics Engineers, Conference | 59 | | Society of Plastic Engineers, Dallas, TX, [online], (Accessed July 22, 2024)


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Created June 1, 2001, Updated February 17, 2017