Thermal conductivity of nanopatterned polymer thin films

• Applicant: Dr. Martin Kreuzer
• Subject Area: Experimental and Theoretical Physics of Polymers ; Synthesis and Properties of Functional Materials ; Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: from 2014 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 255206430

The release and absorption of energy is fundamental to all technological applications, followed by changes in temperature or in local energy. Therefore, easily manageable, cost efficient and environment-friendly materials for heat management are most wanted for numerous applications in nanotechnology, telecommunication and energy harvesting. Polymers fulfil these criteria in a window of parameters that enables high impact materials in the mentioned areas. In particular, the large range of achievable thermal conductivities in polymers from 0.1 to 104 W m-1 K-1, depending primarily on their alignment, makes them a promising material for heat management. The objective of this proposal is the study of thermal properties of block copolymer (BCPs) thin films with respect to alignment and structure. The microphase separation of BCPs will be used for a precise alignment on a nano scale. Alignment will be directed by nanoimprint lithography, which results in more complex nanostructures. Further, functionalization of the polymer thin films will be achieved by the introduction of metal nanoparticles. The BCP films have the potential for controlled anisotropic and directional thermal conductivity characteristics. To our knowledge these crucial studies of patterned and functionalized thin films are still missing and are the objective of the proposed project.The structure of the polymer thin films will be analysed by electron and atomic force microscopy to resolve locally the prepared structures, and in scattering experiments (x-ray reflectivity and GISAXS), to obtain global information about in-plane and out-of-plane periodicity, defectivity and electron density. Heat transfer in the thin films will be measured in-plane and out-of-plane by several state-of-the-art techniques. The combination of structural and thermal characterization is especially important in the nano scale since their connection lies at the heart of understanding energy transfer processes.

• DFG Programme: Research Fellowships
• International Connection: Spain
• Host: Professorin Dr. Clivia Marfa Sotomayor Torres