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McHugh, Anthony J. Barton, Benjamin Fredrick 2015-09-25T20:44:10Z 2015-09-25T20:44:10Z 10000-01-01 1998 1998 The Cahn-Hilliard approach is extended to the study of phase separation in ternary polymer/solvent/nonsolvent systems. Three systems are studied: PMMA/N-methyl-2-pyrrolidinone [NMP]/glycerol, for which experimental data are available, and two common membrane-forming systems, poly(ether sulfone) [PES]/dimethylsulfoxide [DMSO]/water and cellulose acetate [CA]/acetone/water. The effects of quench temperature and initial solution composition on the predicted structure-formation dynamics are elucidated. For the PMMA/NMP/glycerol system, model predictions agree well with real-time data obtained from light scattering measurements. Predicted pore growth rate curves exhibit a relative maximum with both quench temperature and nonsolvent composition. For shallow quenches (higher quench temperatures and lower nonsolvent content) near a phase boundary, the pore growth rate increases with increasing quench depth while for deep quenches, where the composition of the polymer rich phase approaches that of a glass, the pore growth rate decreases with increasing quench depth. This behavior seems to be a universal phenomenon in quenched polymer solutions which can undergo a glass transition, and is result of an interplay between thermodynamic and kinetic driving forces for phase separation. Made available in DSpace on 2015-09-25T20:44:10Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 9912189.pdf: 3169804 bytes, checksum: 60a7386c32bd8a08f278bdd8a0d9db5c (MD5) Previous issue date: 1998 Embargo set by: Seth Robbins for item 83737 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only 152 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1998. http://hdl.handle.net/2142/82456 (MiAaPQ)AAI9912189 eng Engineering, Chemical Dynamics of Membrane Structure Formation in Quenched Polymer Solutions text Chemical Engineering Chemical Engineering University of Illinois at Urbana-Champaign Dissertation Ph.D.