Graduate Seminar
Tuesday, June 3, 2008
10:30am
Bossone 302
Dissolution of Glassy Polymers
Gerard Klinzing
Advisor: Dr. Antonios Zavaliangos
Abstract
The dissolution of glassy polymers is an important area of research in engineering and polymer science. The use of different solvents for dissolution has a profound impact throughout industry in applications such as microlithography, membrane science, plastic recycling, and drug delivery. Polymer dissolution differs from that of non-polymeric systems because polymers do not dissolve instantly upon constant with a solvent. Polymer chains require time to relax and disentangle before entering solution thus creating two moving boundaries layers consisting of a polymer glassy core- gel interface and a gel-solvent interface. It is possible to predict whether dissolution will occur by examining the difference between the solubility parameters of the solvent and polymer. Several different factors such as polymer molecular weight, polymer dispersity, tacticity, and solvent affect the rate of dissolution. Numerous models have been formulated to describe the dissolution process which includes phenomenological models using Fickian equations, external mass transfer models, reptation models, and a dissolution clock model. In order to characterize the physical process different experimental techniques have been utilized to study the rate of dissolution. These techniques include refractometry, optical microscopy, laser interferometry, nuclear magnetic resonance imaging, FT-IR, and micro-computed tomography. Research over the past two decades has steadily increased with respect to polymer dissolution and currently research is diverse with several applications in the field of battery technology and hydrogel polymers.
[loc] Bossone 302 [/loc]