10:30am - 11:00amInvited
Design and Characterization of (Natural Clay Nanotube/Polymer) Hybrids
Kyushu University, Japan
Surface functionalization of tubular nano-clays of imogolite and halloysite using the selective binding of organophosphonic acids and organosilane compounds, and the use of the surface modified nanotubes in polymer hybrids were studied. Surface modification of imogolite with alkyl phosphonic acid salt through the specific interaction of phosphonic acid and the exterior alumina sites of imogolite was presented. SI-ATRP was performed with the selectively adsorbed phosphonic acid functionalized ATRP-initiator to prepare polymer brushes on the imogolite surface. Selective modification of halloysite nanotube exterior and inner surfaces was demonstrated. Aqueous phosphonic acid binds to alumina sites at the tube lumen to make the lumen hydrophobic. Subsequent modification with organosilane affords bifunctionalized halloysites with both the lumen and exterior surface modified. Loading of hydrophobic organic compound to the modified lumen was confirmed. SI-ATRP was performed through the selectively adsorbed DOPA-functionalized ATRP-initiator to prepare polymer brushes on the nanotube lumen. Also, surface modified halloysite was applied for preparation of novel intelligent polyurethane nanocomposites with improved thermal stability and mechanical properties.
11:00am - 11:30amInvited
Organic-Inorganic Hybrid Nanomaterials and Applications
Cornell University, United States
Global problems including energy conversion and storage, clean water and human health require increasingly complex, multi-component hybrid materials with unprecedented control over composition, structure, and order down to the nanoscale. This talk will give examples for the rational design of novel functional organic-inorganic hybrid materials inspired by biological examples. Discussion will include formation of organic-inorganic hybrid nanoparticles as well as polymer-nanoparticle self-assembly derived synthetic porous materials with amorphous, polycrystalline, and epitaxially grown single-crystal structures. Experiments will be compared to theoretical predictions to provide physical insights into formation principles. The aim of the described work is to understand the underlying fundamental chemical, thermodynamic and kinetic formation principles enabling generalization of results over a wide class of materials systems. Examples will cover the formation of hierarchical structures at equilibrium as well as via processes far away from equilibrium. Targeted applications of the prepared systems will include the development of fluorescent hybrid probes for nanomedicine, nanostructured hybrids for energy conversion and storage devices, as well as the formation of first self-assembled superconductors.
 S. W. Robbins, P. A. Beaucage, H. Sai, K. W. Tan, J. P. Sethna, F. J. DiSalvo, S. M. Gruner, R. B. van Dover, U. Wiesner, Block copolymer self-assembly directed synthesis of mesoporous gyroidal superconductors, Sci. Adv. 2 (2016), e1501119.
 K. W. Tan, B. Jung, J. G. Werner, E. R. Rhoades, M. O. Thompson, U. Wiesner, Transient Laser Heating Induced Hierarchical Porous Structures from Block Copolymer Directed Self-Assembly, Science 349 (2015), 54-58.
 E. Phillips, O. Penate-Medina, P. B. Zanzonico, R. D. Carvajal, P. Mohan, Y. Ye, J. Humm, M. Gönen, H. Kaliagian, H. Schöder, H. W. Strauss, S. M. Larson, U. Wiesner, M. S. Bradbury, Clinical translation of an ultrasmall inorganic optical-PET imaging nanoparticle probe, Sci. Transl. Med. 6 (2014), 260ra149.
11:30am - 11:45amOral
Compactly and Vertically Aligned Graphene Film/Epoxy Composites for Heat Management
Department of Materials Science and Engineering, CAPT/HEDPS, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Engineering, Peking University, China
A novel composite consisting of vertically aligned graphene film and epoxy was designed and manufactured. A remarkable enhancement of mechanical properties and thermal conductivity is demonstrated. The fractured surfaces of the composite show hierarchical structure of graphene film and epoxy for heat transport. Vertically aligned structure constructed by continuous graphene films forms effective fast channels for heat removal. The thermal conductivity of composites reaches 384.9 Wm-1K-1 at 44 vol% graphene, a dramatic enhancement of 3570% per vol% compared to the pure epoxy. This value is almost the highest of all epoxy based composites. The cooling performance of the LED package with the application of GF/E composites is enhanced by reducing LED chip temperature of about 20oC compared with the application of pure epoxy. The GF/E composite is proved to be a potential material for heat management of LED or other electronic devices.
The work is supported by NSFC and NSFC-RGC Joint Research Scheme (Nos.11361161001, CUHK450/13 and 11672002).
11:45am - 12:00pmOral
High Efficient Low Cost Photochromic Material for Smart Window
Singapore Institute of Manufacturing Technology, Agency for Science, Technology and Research (A*STAR), Singapore
Photochromic materials which change colors in a persistent but reversible manner resulting from photochemical-induced reactions, have attracted much attention for a variety of applications such as photochromic displays, photochromic sensors, photochromic fabric materials and decorations as well as the energy saving smart windows. Currently, most of the mature photochromic technologies relay on organic photochromic materials such as naphthopyrans, spiropyrans and spirooxazines. However, these organic materials are not suitable for large scale smart window applications due to the high cost and low resistance to long term light irradiation. Inorganic photochromic materials, in contrary, have good thermal and chemical stability, but the color change usually not dense enough with slow response and poor irreversibility. Among them, Tungsten oxide is a wide band gap semiconductor and one of the most studied inorganic species for photochromic application. One method to improve the photochromic behaviour of inorganic materials is to fabricate organic-inorganic hybrid nanocomposites. In this work, we report our research work on WO3-Sol-gel based hybrid material. The new material developed shows a very dense color change and fast photo-response behaviour. Upon UV light or outdoor sunlight excitation, the new photochromic material changes color from transparent (light transmittance > 80%) to dark blue (light transmittance <10%) in only 5-6 mins. The reversibility of the photochromic material is also great and maintains same color after 10 coloration-bleaching cycles. The polyoxometalates crystal structure and kinetics of colour change are analysed by XRD and FTIR. The influence of synthesis parameters on photochromic performance is investigated.