One of our NSEC’s senior faculty participants, Dr. Charles F. Zukoski, was elected to the National Academy of Engineering. He was cited “for research on the manipulation of particle interactions to alter their suspension properties, and for leadership in education.” Figure 1. Anisotropic particle suspensions. His research concentrates on understanding the relationships between surface physical chemistry and the material properties of colloidal suspensions. Particular attention is paid to methods of manipulating interparticle forces to alter particle and suspension properties. Zukoski is the William H. and Janet G. Lycan Professor in the Department of Chemical and Biomolecular Engineering and Vice Chancellor for Research at the University of Illinois at Urbana- Champaign. Photo Credits: Nanoscience and Engineering Center (NSEC) for Directed Assembly of Nanostructures Richard Siegel, Rensselaer Polytechnic Institute, DMR

Nanoscience and Engineering Center (NSEC) for Directed Assembly of Nanostructures Richard Siegel, Rensselaer Polytechnic Institute, DMR NSEC investigators Dr. Chang Y. Ryu and Brian C. Benicewicz authored one of the ten most-accessed articles in the journal Macromolecules (April-June, 2006). The article’s popularity mirrors the scientific impact of this work. Macromolecules is the most-cited journal in the area of Polymer Science, with 71,840 citations in over 41,000 more citations than the nearest ranked journal. It is also ranked third in impact factor out of the 75 journals in the polymer science category. The article, “A Versatile Method To Prepare RAFT Agent Anchored Substrates and the Preparation of PMMA Grafted Nanoparticles” was co-authored by Li, Han, Ryu, and Benicewicz. Researchers discovered a novel strategy to efficiently graft polymers on nanoparticle surfaces using a controlled radical polymerization technique. This strategy is applicable for a wide range of monomers to tailor the surface functionality of nanofillers including nanoparticles. C. Li (RPI), J. Han (RPI), C.Y. Ryu (RPI), and B.C. Benicewicz (RPI), “A Versatile Method to Prepare RAFT Agent Anchored Substrates and the Preparation of PMMA Grafted Nanoparticles”, Macromolecules 2006, 39, Figure 2. Chain transfer reactions for the radicals (a) in solution and (b) on particle surfaces.

Rensselaer NSEC Room Temperature Assembly of Germanium Nanoparticle-based Photonic Crystals Through a rapid and low-cost directed self-assembly process, a nanoparticle-based photonic crystal, a three- dimensionally periodic material with unique and powerful optical properties, was formed (Braun, Siegel). Our photonic crystals exhibited the greatest photonic strength to date of any nanoparticle- based systems, and in addition, we demonstrated, for the first time, that germanium nanoparticles could be directly used to create a photonic crystal. Reflectance spectroscopy, in conjunction with appropriate theoretical models, was used to determine that the germanium photonic crystal had a refractive index contrast of 2.05, the largest refractive index contrast obtained to date for any nanoparticle-based system. R.G. Shimmin (UIUC), R. Vajtai (RPI), R.W. Siegel (RPI), P.V. Braun (UIUC), “Room-Temperature Assembly of Germanium Photonic Crystals through Colloidal Crystal Templating”, Chem. Mater., 2007, ASAP Article, DOI: /cm062893l. Figure 3. Germanium nanoparticles (A) were infilled into the interstitial space of a colloidal crystal (B) formed from 1 micrometer diameter polymer microspheres. The germanium nanoparticles were linked together using a photocurable epoxy, and the polymer microspheres were dissolved, forming a germanium-based photonic crystal (C). Nanoscience and Engineering Center (NSEC) for Directed Assembly of Nanostructures Richard Siegel, Rensselaer Polytechnic Institute, DMR

Rensselaer NSEC Chain Conformations and Bound Layer Correlations in Polymer Nanocomposites Our novel microscopic statistical mechanical theory of polymer nanocomposites also predicts the existence of a thin thermodynamically stable bound layer of polymer surrounding dispersed fillers. The experimental polymer scattering signature of this phenomenon is a peak in the SANS spectrum, whose intensity and location are controlled by nanoparticle size and volume fraction. The neutron data are consistent with these predictions thereby providing the first evidence for the existence of nanoscopic layers that play a critical role in promoting miscibility and good filler dispersion. S. Sen (RPI), Y. Xie (RPI), S.K. Kumar (RPI), H. Yang (RPI), A. Bansal (GE), D.L. Ho (NIST), L. Hall (UIUC), J.B. Hooper (UIUC) and K.S. Schweizer (UIUC), “Chain Conformations and Bound Layer Correlations in Polymer Nanocomposites”, Physical Review Letters, 98, (2007). Figure 4. Schematic of fillers with bound polymer layers dispersed in a homopolymer matrix. A combined experimental and theoretical approach (Kumar, Schweizer) has been employed to address the open question of chain conformation and adsorption in polymer nanocomposites. Small angle neutron scattering (SANS) on mixtures of polystyrene and nanosilica has unequivocally shown that polymers adopt random coil shapes, whose sizes are independent of molecular weight and nanofiller concentration. Nanoscience and Engineering Center (NSEC) for Directed Assembly of Nanostructures Richard Siegel, Rensselaer Polytechnic Institute, DMR

Rensselaer NSEC Enzyme-catalyzed Directed Assembly of Organogels Figure 5. Enzyme-catalyzed directed assembly of organogels. Lipase catalysis in acetone results in a region-selective and symmetrical diester of the sugar trehalose. The sugar derivatives undergo self-assembly to yield nanoscale fibers that trap organic solvent molecules. Acrylate derivatives can be polymerized to yield crosslinked hydrogel materials. Nanoscience and Engineering Center (NSEC) for Directed Assembly of Nanostructures Richard Siegel, Rensselaer Polytechnic Institute, DMR

Rensselaer NSEC Enzyme-catalyzed Directed Assembly of Organogels (Cont.) Organogelators with excellent ability to gel a broad range of organic solvents as well as natural oils (olive and vegetable oils) were synthesized (Dordick) using all natural building blocks (sugars, fatty acids, and enzymes). This is an example of exquisitely selective enzyme-catalyzed directed assembly - chemical synthesis of the gelators results in poor gel properties due to the lack of selectivity. With their ability to assemble at the nanoscale, and to be prepared from all natural building blocks (sugars, fatty acids, and enzymes), these gelators may be used to encapsulate pharma-ceutical, food, and cosmetic products and to build 3-D biological scaffolds for tissue engineering. G. John (CUNY), G. Zhu (RPI), J. Li (USM), and J.S. Dordick (RPI), “Enzymatically Derived Sugar-Containing Self-Assembled Organogels with Nanostructured Morphologies”, Angew. Chem. Int. Ed. Engl. 45, (2006, Cover Article). Nanoscience and Engineering Center (NSEC) for Directed Assembly of Nanostructures Richard Siegel, Rensselaer Polytechnic Institute, DMR

Rensselaer NSEC Cellulose Nanotube Composites as Flexible Power Sources Nanocomposites have been developed that have enhanced biocompatibility while still exhibiting important properties associated with nanomaterials (Linhardt, Ajayan). Nanoporous cellulose-heparin composites were prepared as blood compatible membranes for kidney dialysis and as electrospun fibers for woven vascular grafts. Of significant interest in combining biological and materials applications, cellulose-oriented carbon nanotube composites have been prepared, which contain ionic liquids as batteries and supercapacitors and a patent application filed. These flexible, biocompatible devices are being evaluated in a number of applications such as implantable and wearable power sources for medical assist devices. Figure 6. Multi-wall carbon nanotubes aligned in cellulose and with room temperature ionic liquids as a conductive medium result in unique flexible batteries. S. Murugesan (RPI), S. Mousa (RPI), A. Vijayaraghavan (RPI), P.M. Ajayan (RPI), and R.J. Linhardt (RPI), “Ionic liquid derived blood compatible composite membranes for kidney dialysis”, J. Biomed. Mat. Res. Part B - Appl. Biomater. 79B, (2006). G. Viswanathan (RPI), S. Murugesan (RPI), V. Pushparaj (RPI), O. Nalamasu (RPI), P.M. Ajayan (RPI), and R.J. Linhardt (RPI), “Preparation of biopolymer fibers using electrospinning from room temperature ionic liquids”, Biomacromol. 7, (2006). Nanoscience and Engineering Center (NSEC) for Directed Assembly of Nanostructures Richard Siegel, Rensselaer Polytechnic Institute, DMR

Rensselaer NSEC Audiences Enriched by Molecularium TM : Riding Snowflakes The Associated Press declares, “this high-octane show is a new answer to a question dogging many educators: How do you get young kids interested in science?” Independent assessment at the Chabot Space and Science Center in Oakland CA, including 1,172 viewers, confirms that people of all ages enjoy and learn from Molecularium: Riding Snowflakes (Garde, Schadler, Siegel). Key findings include the following. Over 75% of viewers rated the show an 8 out of 10 or higher, with 63% giving the show a 10 out of 10. Over 75% of viewers rated the show an 8 out of 10 or higher, with 63% giving the show a 10 out of 10. Across all age groups, the total percentages of correct answers increased significantly after having watched the show, while incorrect and “not sure” answers decreased significantly. Across all age groups, the total percentages of correct answers increased significantly after having watched the show, while incorrect and “not sure” answers decreased significantly. With younger audiences, the percentage of correct responses more than doubled after watching the show. With younger audiences, the percentage of correct responses more than doubled after watching the show. Figure 7. A digital dome screen shot from Riding Snowflakes. Nanoscience and Engineering Center (NSEC) for Directed Assembly of Nanostructures Richard Siegel, Rensselaer Polytechnic Institute, DMR

Rensselaer NSEC Leadership Series Drives Students’ Professional Development Our NSEC (Schadler) has co-sponsored a Professional Leadership Series (PLS), facilitated by the Archer Center for Student Leadership Development (RPI), for graduate students. This course is enjoying unprecedented success after being offered during the Fall and Spring semesters for nearly five years. In particular, course enrollment, guest speaker participation, and positive assessment have reached an all time high during the last two semesters. Figure 8. In a team activity, which explores communication and group dynamics, students work together to construct specific structures based upon one team member’s observation of the model. Executives from companies such as BAE Systems, Boeing, Extreme Molding, General Dynamics, GE, IBM, Knowles Atomic Power, Rensselaer County Regional Chamber of Commerce, Saint-Gobain, and W.L. Gore have recognized the value of this course and volunteered their time to share their perspectives on course topics. Engineering, science, and management students are drawn to the interactive course format, which explores the individual qualities of a leader (e.g., ethical decision making, motivation, vision) as well as the functional capacities of leadership (e.g., effective communication, managing conflict, team development). A recent participant shared in their assessment of the course, “[PLS] forces you to think about yourself as a team member and enhance your own role ~ ethically and goal oriented.” Nanoscience and Engineering Center (NSEC) for Directed Assembly of Nanostructures Richard Siegel, Rensselaer Polytechnic Institute, DMR

Rensselaer NSEC New Render Farm Built for Visualizing Nanoscale Universe NSEC has built a new render farm for the Molecularium project that is capable of creating IMAX quality animation. A render farm is a collection of a large number of specialized computer systems used to produce feature length animation. The power and size of the Molecularium render farm places it among the top ranks of university-based render farm facilities. This facility includes more than 63 terabytes of disk, 40 terabytes of back-up tape, 160 CPU cores, and 300 gigabytes of RAM. Whereas other university render farms are utilized for architecture, geophysics, or purely animation and digital media studies, the Molecularium render farm at Rensselaer is uniquely dedicated to the scientific visualization and animation of the nanoscale universe (Siegel, Schadler, Garde) for public science literacy education and research. Figure 9. Photo of render farm, primary systems. Nanoscience and Engineering Center (NSEC) for Directed Assembly of Nanostructures Richard Siegel, Rensselaer Polytechnic Institute, DMR

Rensselaer NSEC NSEC and Albany International Joint Research Leads to New Technology The unique university-industry partnership model in place at our NSEC at RPI continues to foster well- established partnerships with leading multinational companies. Albany International, Inc. has played a key role as one of the Center’s original industrial partners. Joint research between Rensselaer (Siegel, Schadler) and Albany International led to polymer nanocomposites with greatly improved mechanical properties. This has enabled Albany International to develop a new class of materials for use in coating technology and industrial belt applications. Albany International is currently at the scale-up stage of introducing this new product into their engineered fabrics. Figure 10. Illustration of industrial belt application of new coating technology. Nanoscience and Engineering Center (NSEC) for Directed Assembly of Nanostructures Richard Siegel, Rensselaer Polytechnic Institute, DMR