2020 Virtual AIChE Annual Meeting
(553e) Multilayer Coextruded Polyolefin Films Improve Processability and Reduce Flammability
Authors
Christopher W. Macosko - Presenter, University of Minnesota
Frank S. Bates, University of Minnesota
Bongjoon Lee, University of Minnesota
Alex M. Jordan, University of Minnesota
Kyungtae Kim, University of Minnesota
Ehsan Behzadfar, Lakehead University
Via multilayer coextrusion we have fabricated films consisting of 100s of layers of polypropylene (PP) and polyethylene (PE). Although neither polymer shows strain hardening during extension the multilayers have extensional viscosities significantly greater than what is predicted with a simple 2-component volume average model. This behavior is predicted with a 3-component model that accounts for the many PE/PP interfaces using only interfacial tension as a model fitting parameter ( A.M. Jordan et al. J. Rheol. 2019). The extracted interfacial tension from transient elongational viscosity measurements agrees with the interfacial tension extracted from fitting small amplitude oscillatory shear data with the Palierne model. These multilayer PP/PE films opened the temperature and time operating window for thermoforming and reduced dripping during burning.
