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Title:Crystallization kinetics of polymer melts in extensional flow
Author(s):Tree, David Alan
Doctoral Committee Chair(s):McHugh, Anthony J.
Department / Program:Chemical and Biomolecular Engineering
Discipline:Chemical Engineering
Degree Granting Institution:University of Illinois at Urbana-Champaign
Subject(s):Engineering, Chemical
Abstract:A technique to study the kinetics of flow-induced crystallization of polymers in extensional flow has been developed which uses a 4-Roll Mill. The kinetics of a High Density Polyethylene were found to be well described by the Avrami treatment, indicated that the crystallization occurred by sporadic nucleation and one-dimensional growth and were a strong function of temperature and applied stress but were independent of strain history. The kinetics were found to be consistent with the Ziabicki theory for strain-induced crystallization but inconsistent with the theory of uttermost uniformity and an elevated melting point mechanism. The kinematics and stress fields of the 4-Roll Mill flow were measured independently by a tracer particle technique and an application of the Method of Isoclinics respectively allowing comparison to the predictions of several rheological equations of state. The deformation of a polymer droplet suspended in a carrier phase at low Reynolds number and high Weber number was documented. It is recommended that the 4-Roll Mill technique be used for study of other crystallizable polymer systems.
Issue Date:1990
Rights Information:Copyright 1990 Tree, David Alan
Date Available in IDEALS:2011-05-07
Identifier in Online Catalog:AAI9114443
OCLC Identifier:(UMI)AAI9114443

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