1. Materials World Network: US-Russia Collaboration on Responsive Micelles at Surfaces – A combined Experimental and Theoretical Approach Svetlana Sukhishvili, Stevens Institute of Technology, DMR 0710591 The objective of this project is to explore layer-by-layer (LbL) self-assembly of temperature- and pH-responsive block copolymer micelles with polyelectrolytes (PEs) at surfaces. Using synthesized neutral and ionic diblock copolymers, we have constructed temperature- and pH- responsive micelles and deposited them within thin surface coatings using LbL technique. Our results are featured in six papers published or under revision and four conference proceedings. In solutions of micelles with weak PE coronae, we have observed novel pH-induced phase transitions between large, weakly charged and small, strongly charged micelles (Fig. 1) 1. Among micelles with PE cores, we found a new type of micelle with ionomer-like cores 2. Both phenomena were studied theoretically and experimentally. At surfaces, we have constructed novel biocompatible, pH- stable 3,4, as well as temperature-erasable LbL films 5. We showed that within multilayers, micelles with either pH- dissolvable or temperature-dissolvable cores were stabilized due to binding with a homopolymer, and provided control over reversible film swelling and delivery of incorporated functional molecules (Fig. 2) 6. Future applications of such functional polymer films include controlled delivery of chemicals from surfaces. Fig. 1. pH-induced changes of size of PDMA-b-PNIPAM 7 micelles. Insets: AFM images of smaller and larger micelles 8. Fig. 2. Temperature-induced swelling (A), micellar core expansion (B,C), and reversible release of pyrene from (PVPON-b-PNIPAM micelles/PMAA) 4 films 9 (D, E).

2. International collaboration with Russian counterparts has grown stronger, and included trips of graduate students and the PI to Russia, joint participation in an international conference, (Fig.1), writing papers and planning to enhance an international aspect of a student conference in St. Petersburg (Russia) in October 2009. Results of the project have been incorporated into two 2008/2009 graduate courses: CH671 “Polymers at Solid-Liquid Interfaces” and CH525 “Techniques of Surface and Nanostructure Characterization”, and presented in seven invited talks at universities and international conferences 1, as well as at the Research and Entrepreneurship Day at Stevens in May 2009 which gathers a broad audience of NY/NJ entrepreneurs, National Lab representatives, and high school teachers. Importantly, the project has further energized the involvement of undergraduate and high school students in our research (Fig.2). Technological output of our research includes development of environmentally triggered polymer matrices for controlled delivery of active components from surfaces, such as coatings on dental implant surfaces. Fig. 1. US-Russia collaboration developing. Left: PI Sukhishvili (US, left) and Kramarenko (Russia, right) discuss results of the project in December 2008. Right: Ph.D. students Elena Nyrkova (Russia, left) and Irem Erel (US, right) during discussion of their joint paper. Materials World Network: US-Russia Collaboration on Responsive Micelles at Surfaces – A combined Experimental and Theoretical Approach Svetlana Sukhishvili, Stevens Institute of Technology, DMR 0710591 Fig. 2. Graduate, undergraduate and high-school students participate in the project in summer of 2009: senior students Lauren Spagnuolo (in grey, left; Stevens, NJ), and Diana Lee (in grey, right; The Cooper Union, NY), and high school students Diego Barriga (in white, left; ACS SEED program) and Dipixa Rathod (in white, right; Partners in Science Program, Liberty Science Center, NJ).