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Department of Chemical and Biological Engineering. September 26, 2013. Sri Harsha Kalluru , Lee Trask, Jace Dendor , Nac ú Hernández, Eric Cochran. Bioseparation/Hydrogen Fuel Cells. Thermoplastic Elastomers via polyolefin/layered silicate Nano composites.
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Department of Chemical and Biological Engineering • September 26, 2013 Sri HarshaKalluru, Lee Trask, JaceDendor, Nacú Hernández, Eric Cochran Bioseparation/Hydrogen Fuel Cells Thermoplastic Elastomers via polyolefin/layered silicate Nano composites • Some areas of interest, in the use of block copolymers, are: • Alternative power sources, more specifically cathode catalyst layers (CCLs) for Hydrogen fuel cells. • Bioseparation of compounds otherwise inseparable using normal separation techniques • Composite: Formed from different materials (Filler, matrix); superior properties compared to its constituent materials • Nanocomposite: material in which at least one dimension of the filler is in nanometer scale range • Filler gives high strength and high surface area to volume ratio • Main applications: • Fuel Cells • Bio-separations • Tissue engineering • Immobilization of proteins • Drug delivery • Barrier materials (packaging industry) • Thermally stable polymers • Flame retardant polymers • High performance thermoplastics/thermoplastic elastomers Intercalated vs Exfoliated Block copolymers: • Twoor more distinctpolymerchainscovalentlybondedtooneanother. • Macrophase separation not possible • Microphase separation occurs ( Self-assembly) • Chemical incompatibilities • Creation of nano-ordered structures Organic modification of MMT surface to compatibilize it with the polymer • Physical, mechanical and thermal properties will be enhanced with very little amount of filler addition • Rate of mass transfer rate of monomer into inter-gallery space and rate of polymerization determines extent of exfoliation in nanocomposites Nanocomposite hydrogel Carbon nano tube nanocompsoites to prevent bio fouling Nanocomposites for gas barriers • We make use of block copolymers (BCPs) to reduce dependency on oil. • We are designing and developing new nanomaterials that would be able to be used in energy producing • devices, providing “green” substitutes to petroleum based products TEM micrographs showing sections of block copolymer nanocomposites Mathematical Modeling • Material physics are transformed in governing equations. • Propagator equations describe how polymers Computer Simulation • Efficient numerical methods are required to reduce runtime of simulations. • High-performance computing options allow large calculations to proceed simultaneously. New material physics are identified from mathematical identities and manipulation. Equations are solved using numerical method. Functionalized MMT plates Dispersion of platelets Monomer diffusion Anisotropic brushes Dissolution in 2nd monomer Isotropic brushes • Gaussian Coils describe the behavior of flexible polymers • Rigid rods characterize cylindrical polymers Smart step-sizes improve properties of existing methods 1st monomer brushes Polymer Self-Consistent Field Theory Right) Professor Luecke next to ISU’s Lightning supercomputer. Left) Our program provides some functionality to run on NVidia video cards. • Physical Systems of Interest • Polymer nanocomposites consists of particles added to the polymer solution. • Rod-coil block copolymers consist of a rigid polymer connected to a flexible polymer. Calculated Properties • Density fields describe where a particular monomer type resides. • Other properties can be calculated from mathematical relationships. This obviates the need for expensive laboratory experiments that are difficult to characterize. Material properties are matched with simulation parameters. With this cycle, novel materials are produced based on simulation results. Density fields from a 2D rod-coil diblock copolymer simulation with coil homopolymer. Left) Rod specie density. Middle) Total coil specie density. Right) Coil block density. Due to the wide array of possible ordered structures, block copolymers can be used in many different applications. Right) Particles (Chlorophyll) are dispersed in a diblock copolymer to harvest light. Left) Flexible organic electronics sheets are made from rod-coil block copolymers. Acknowledgements
Department of Chemical and Biological Engineering • September 26, 2013 Mengguo Yan, Michael Forrester, Austin Hohmann, Nacú Hernández, Eric Cochran Biopolymers Biopolymers are materials partially or entirely produced from renewable natural resources other than petroleum. Our group is interested in using vegetable oils and their derivatives and transforming them into higher value products (biopolymers). What are they? Vegetable oils are composed of triglycerides, which posses an average of 4.6 double bonds that with some chemical modification we are able to synthesize polymers using different polymerization techniques. Such as Atom Transfer Radical Polymerization (ATRP) or Reversible Addition Fragmentation Chain Transfer. (RAFT). Howwe do it? Glycerol molecule We have partnered with industry to scale-up the production of these biopolymers. A pilot plant capable of producing 10 tons/week of these materials is being build in university grounds. Benefits Their raw materials used are readily available, higher biodegradability and recyclability, lower process energy requirements, thus having a less negative environmental impact. Applications • As a substitute of butadiene or most commonly know as “rubber” • Asphalt modification • Adhesives • Paints and coatings • Clothing and textiles • As an additive to soils • Glycerol is a biodegradable substance and has excellent adhesive properties, it is believed that it can be used to help give extra structural stability to structures built on soil modified with poly acrylated glycerol (PAG). • Given the fact that it is bio-degradable as well as bio-renewable it has excellent potential to have positive industrial applications and many of these are still being explored. Acknowledgements