1. Benny D. Freeman Department of Chemical Engineering University of Texas at Austin, Office: CPE 3.466 Tel.: (512)232-2803, e-mail: freeman@che.utexas.edu http://www.che.utexas.edu/graduate_research/freeman.htm http://membrane.ces.utexas.edu March 2004 Transport of Small Molecules in Polymers: Overview of Research Activities

2. Develop fundamental structure/function rules to guide the preparation of novel, high performance polymers or polymer-based materials for gas and liquid separations as well as barrier packaging applications. Focus

3. 11 Ph.D. students: –Gas Separations: Scott Matteucci, Roy Raharjo, Scott Kelman, Rajeev Prabhakar, Haiqing Lin –Liquid Separations: Conor Braman, Alyson Sagle, Bryan McCloskey, Hao Ju, Yuan-Hsuan Wu –Barrier Materials: Keith Ashcraft Administrative assistant: Sande Storey Sponsors: –NSF - 1 project –DOE - 3 projects –Office of Naval Research - 4 projects –Industrial sponsors: Pall Corp., Air Liquide, Eastman Chemical Current Group/Program Profile

4. Growing demand for packaging oxygen sensitive products in flexible, polymer-based containers (food & beverage packaging, microelectronic components, pharmaceutical agents, etc.) Most polymer packaging does not have sufficient oxygen barrier to meet new applications. Recent discoveries in industry have shown that adding certain salts to polymers can markedly increase the oxygen barrier properties, but there are no fundamental studies of the mechanism, kinetics, etc. of these systems to serve as a basis for optimization. Reactive Oxygen Barrier Materials

5. Example of Oxygen Scavenging with Cobalt Salt in MXD6 Nylon PET = poly(ethylene terephthalate), one of the most widely used packaging materials known.

6. Filled Polymer Membranes: Background Nonporous, impermeable filler Data of Barrer et al., Journal of Polymer Science, 1, 2565-2586 (1963).

7. Effect of Silica Nanoparticles on PMP Permeability and Mixed-Gas Selectivity Effect of Silica Nanoparticles on PMP Permeability and Mixed-Gas Selectivity 2 % n-butane / 98% methane feed; upstream pressure = 150 psig; downstream pressure = 0 psig s: Barrer et al., Journal of Polymer Science, 1, 1963 : Most, Journal of Applied Polymer Science, 14, 1970 Merkel et al., Ultrapermeable, Reverse-Selective Nanocomposite Membranes, Science, 296, 519-522 (2002).

8. Organic rejection (i.e., oil + surfactant) is >95%. Problem with Conventional Membranes: Fouling

9. Nonporous Pebax 4011 coating Microporous PVDF support Pebax 4011: 57 wt% PEG, 43 wt. % PA6: Nonporous Pebax 4011 Coating on Porous PVDF

10. Pebax 4011: 57 wt% PEG, 43 wt. % PA6: Fouling Properties of Pebax 4011 Coated Membrane and Conventional Porous Membrane

11. Membrane Area: 1 m 2 10,000 ppm motor oil/1000 ppm surfactant in water 1,000 ppm motor oil + surfactant in water (90% rejection) 100 ppm motor oil + surfactant in water (99% rejection) Separation Properties of Pebax 1074/PDVF Composite Spiral Wound Membrane Modules

12. Chitosan Direct attachment Bis(sulfosuccinimdyl) suberate Glutaraldehyde Hydroxyethyl Cellulose Direct attachment 4-nitrophenyl chloroformate Enzymes were immobilized onto the membranes using many different surface activation strategies Attachment Chemistries

13. Coupling of Enzymes Chitosan-N=CH-(CH 2 ) 3 -CHO +  Chitosan-N=CH-(CH 2 ) 3 -CH=N-Enzyme H 2 N-(CH 2 ) 4 -  -chymotrypsin Enzyme Coupling to Chitosan Membranes

14. Membranes exposed to 1% BSA at for 23 days and at 3% for 2 days in a continuous loop permeation system. Porous PVDF membrane exhibits obvious surface fouling; the other samples do not. BSA rejection for all samples was approx. 99%. Initial Memzyme Fouling Results