1. Accomplishments in the third year: Thus far, three papers have been published in 2008 and one manuscript entitled “Induced smectic phase in mixtures of hyperbranched polyester and eutectic liquid crystals,” has been communicated to J. Phys. Chem. for publication. Objectives: Fabricate photonic crystals based on wave interference photolithography Elucidate mechanisms of photopolymerization induced crystallization or liquid crystal ordering Extend to relevant photochromic systems. Photopolymerization Induced Phase Transition and Evolution of Morphology Landscape in Holographic Polymer Dispersed Liquid Crystals and Photonic Crystals Thein Kyu, University of Akron, DMR 0514942 Discovery: The phase diagram of blends of photochromic molecule (spiropyran) and mesogenic diacrylate (RM257) has been constructed experimentally and theoretically. The theoretical calculation was carried out by self- consistently solving the combined free energies of Flory-Huggins, Maier-Saupe, and phase field theory. The simulated phase diagram exhibits various coexistence regions involving single phase mesophases and several coexistence phases (Cr + I; Cr + N; Cr + Cr). These predicted coexistence regions have been confirmed by conducting several temperature quenchings into these coexistence gaps. Guided by the established phase diagram, photo-patterning will be performed on the mixture of spyropyran and RM257 for potential applications including photoresponsive actuators and photonic crystals. Figure 1. Chemical structures and phase diagram of of spiropyran and mesogenic diacrylate with the coexistence regions, showing nematics, crystals + liquid, crystal + nematics and crystal + crystal regions.

2. Collaborations: Currently, the PI’s group has been collaborating internationally with Professor T. Nishikubo’s group of Kanagawa University, Japan, on blends of hyperbranched (HB) polyester and liquid crystals. This collaboration is now expanded to Noria ‘water wheel’ molecule synthesized by the collaborator’s group for ion exchanged membranes. The collaborative work with Dean Shila Garg’s group of the College of Wooster continues. The PI and his graduate student, Mr. T. Hwang, visited the College of Wooster couple of times in Spring 2008 and discuss the research progress and performed some experiments. Broader Impact – Thein Kyu, University of Akron, DMR 0514942 Students Involved: Mr. R. A. Matkar graduated in December 2007 with a thesis entitled “Phase diagram and dynamics of solid-liquid phase transitions of binary crystalline polymer blends,” is currently working as a postdoctoral fellow under Prof. M. Chowdury at Lehigh University. He will join Intel company in August, 2008. Ms. S. Park plans to have her final Ph. D. defense on August 1, 2008 and will graduate by December 2008 with a thesis entitled “Photopolymerization induced crystallization in relation to liquid-solid phase diagrams of blends of poly(ethylene oxide)/multi functional acrylate monomers”. She will join Samsung in September 2008. Mr. P. Rathi (Ph. D. Candidate, Theory and simulation of polymerization induced crystallization and phase separation) is expected to graduate within 6 ~ 9 months. He is currently receiving a co-op training in Vybrant Company, Redwood City, California. Mr. N. Kim, a Ph. D. candidate, is now working on phtoisomerization effect on phase equilibria and photo-patterning of mixtures of functional liquid crystals and photochromic molecules. Mr. T. Hwang, a Ph. D. candidate is working on the induced smectic phenomena of binary liquid crystals. Education Outreach: An NSF-REU student, Harris Lam, a junior student from the Department of Mathematics, University of New Orleans, LA, is currently receiving research training in the PI’s group in Summer, 2008. He has established a phase diagram of spyropyran/mesogenic diacrylate (RM 257) system. Subsequently thermal quenching experiments have been performed into these coexistences regions to confirm predicted coexistence regions of the phase diagram. In addition, he is learning the computer codes for determining the coexistence lines of liquid-liquid and solid-liquid phase transitions. The PI will visit Universidad de Antioquia, Medellin, Colombia in August 2008 to give a short course on multicomponent systems.