1. Mechanical and Transport Behavior of Polymeric Dense Films at Elevated Temperature Anandh Balakrishnan Faculty Advisor: Dr.Alan.R.Greenberg Co-Advisor: Dr.Vivek.P.Khare Co-Advisor: Dr.Vivek.P.Khare Dept of Mechanical Engineering, University of Colorado,Boulder

2. Oct 15thProject Proposal2 Introduction-Membrane Science Membrane Membrane A structure having lateral dimensions much greater than its thickness, through which mass transfer may occur under a variety of driving forces. (Koros,Ma,Shimidzu-1996) A structure having lateral dimensions much greater than its thickness, through which mass transfer may occur under a variety of driving forces. (Koros,Ma,Shimidzu-1996) Membrane types  Knudsen diffusion, molecular sieving, solution diffusion membranes. Membrane types  Knudsen diffusion, molecular sieving, solution diffusion membranes. Industrial Applications: oxygen production, nitrogen production, hydrocarbons. Industrial Applications: oxygen production, nitrogen production, hydrocarbons. Solution diffusion membranes are mostly polymeric owing to cheap costs and ease of fabrication. Solution diffusion membranes are mostly polymeric owing to cheap costs and ease of fabrication. Solution diffusion membranes=> Sorb-diffuse-Desorb. Solution diffusion membranes=> Sorb-diffuse-Desorb. Generic structure of a commercial polymeric solution diffusion membrane. Generic structure of a commercial polymeric solution diffusion membrane. Skin layer (separation takes place here) Skin layer (separation takes place here) Porous support (gives support to skin) Porous support (gives support to skin)

3. Oct 15thProject Proposal3 Technical Background Separation governed by the capability of a membrane to discriminate gas sizes and the driving force of each component. Based on Fick’s Law of diffusion, we have Separation governed by the capability of a membrane to discriminate gas sizes and the driving force of each component. Based on Fick’s Law of diffusion, we have where i,j are two components; f and p are indicative of feed and permeate streams;J is the mass flux;K 1 the ratio of permeabilities; K 2 the ratio of partial pressures of i to j; x is the mole fraction of i/j in feed (f) /permeate streams (P). where i,j are two components; f and p are indicative of feed and permeate streams;J is the mass flux;K 1 the ratio of permeabilities; K 2 the ratio of partial pressures of i to j; x is the mole fraction of i/j in feed (f) /permeate streams (P). For the transport of a single gas through a membrane, Fick’s law is straightforward For the transport of a single gas through a membrane, Fick’s law is straightforward where l is the thickness of the membrane. where l is the thickness of the membrane.

4. Oct 15thProject Proposal4 Problem Statement Polymer membranes exhibit a decline in performance with time, which becomes acute at high temperatures. Polymer membranes exhibit a decline in performance with time, which becomes acute at high temperatures. Reasons?! Reasons?! Decrease in thickness or compaction manifested as a viscoelastic creep response. Decrease in thickness or compaction manifested as a viscoelastic creep response. How?! How?! Compaction  decrease in free volume=>decrease in permeabilities. Compaction  decrease in free volume=>decrease in permeabilities. Previous methods characterize transport and mechanical behavior but measurement is not simultaneous. Previous methods characterize transport and mechanical behavior but measurement is not simultaneous. Coupled measurement required to understand the co-relation between the two behaviors. Coupled measurement required to understand the co-relation between the two behaviors.

5. Oct 15thProject Proposal5 Proposal Perform experiments on a chosen polymer. Perform experiments on a chosen polymer. Choice: poly(methyl methacrylate) (PMMA) and a suitable solvent. Choice: poly(methyl methacrylate) (PMMA) and a suitable solvent. Experimental variables Experimental variables pressure, temperature, film thickness, number of gases. pressure, temperature, film thickness, number of gases. Proposed experimental plan (Thesis plan) Proposed experimental plan (Thesis plan) a) Characterizing polymer : mechanical response, glass transition a) Characterizing polymer : mechanical response, glass transition b) Conducting Transport/Compaction tests in the permeation cum b) Conducting Transport/Compaction tests in the permeation cum compaction cell on my decided experimental variables compaction cell on my decided experimental variables c) Levels of experimentation (to be decided) c) Levels of experimentation (to be decided)

6. Oct 15thProject Proposal6 Schedule of Activities (Fall 2004-Spring 2005) Completed To be completed