Modern Research Topics in Macromolecular Science

Transcription

1 Elite Study Programme in Macromolecular Science Advanced Course Modern Research Topics in Macromolecular Science Faculty of the Elite Study Programme Winter term 2004/05

2 The scope of the advanced course on Modern Research Topics in Macromolecular Science is to introduce the students, coming from different backgrounds, to various facets of the broad and interdisciplinary field of Macromolecular Science. It is intended that the students will get a basic understanding of underling concepts, technical terminology and methodologies in the individual subfields of Macromolecular Science beside their main focus. The offered topics cover the fields macromolecular chemistry, colloidal chemistry, biopolymers, biochemistry, microbiology, polymer physics, biophysics, polymer technology, polymer engineering, theory and simulation of macromolecules. The students will select 7 topics from 13 offered topics. Each individual topic has a length of 10 hours and includes lectures, seminars and laboratory illustrations. In addition the students will have a tour and brief introduction of the research facilities. The following topics will be offered in the winter term 2004/05: Catalysts for Olefin Oligomerization and Polymerization and CHactivation Helmut Alt, Inorganic Chemistry II, Polymerization catalysts The topic covers general aspects of the importance and scope of catalyst research for olefin oligomerization and polymerization and CH activation. First, we give an introduction on synthesis and properties of potential catalysts and give an overview of the structure-property relationships in catalysis (empirical and theoretical approaches). Futhermore we will explain methods and tools to optimize catalysts and methods to heterogenize homogeneous catalysts. In the practical part we give insight how to synthesize and apply a homogeneous catalyst?

3 Polymer foams Volker Altstädt, Polymer Engineering Because of the unique properties of polymer foams, a large number of innovative applications can be realised. These include packaging with reduced material costs, airplane and automotive parts with high strength-toweight ratio, decreased thermal conductivity, and acoustic and mechanical dampening. The first part of the module (5 hours) is focused on the fundamentals of the physics of polymer foams including a basic discussion of commercial foaming processes. Thereby, different types of polymer foams (PP, PS, PUR, particle foams) and their typical properties and applications will be presented. In addition, all critical parameters for the control of cell nucleation, cell growth and volume expansion will be introduced. Finally, it will be revealed how to obtain tailored foam morphologies. Additionally, some special experimental techniques for a better understanding of the foaming processes are presented. This oral part is followed by an experimental session (5 hours) taking place in our laboratory. Thereby, a practical introduction into foam injection moulding and foam extrusion is given using commercial machines. Finally, new trends and promising approaches as well as arising questions will be discussed with the foaming experts of the department of Polymer Engineering. Structure and Dynamics in Polyelectrolytes and Polymer Colloids Matthias Ballauff, Physical Chemistry I, Colloid chemistry In our part we shall focus on research done recently in our group on polyelectrolyte star polymers in solutions. These systems are being studied in our group within a collaboration with Prof. A. Müller of MC I. We have been investigating polyelectrolyte stars by small-angle scattering in dilute and semidilute solutions. This work is combined with MD-simulations in order to elucidate the equilibrium structure of these systems. In a second part we shall focus on work related to colloid particles bearing long polyelectrolyte chains

4 on their surface ( spherical polyelectrolyte brushes ). We have studied the equilibrium structure and the dynamics of these systems by a widespread variety of methods. Moreover, we have analyzed the interaction of the particles with proteins in aqueous solution. Our module will include: an introductory course, project work on small-angle X-ray scattering and light scattering and final seminar Liquid Crystals: From Low Molecular Weight Materials to Elastomers Helmut Brand, Theoretical Physics III The field of liquid crystals will be introduced. In one special topic we cover selected LC phases. The second special topic deals with physical properties and methods. In the project afternoon we will discuss selected literature and in particular the derivation of the Frank elastic energy for a nematic liquid crystal. Fluorescence Microscopy Jürgen Köhler and Lothar Kador, Experimental Physics IV The combination of microscopy and fluorescence spectroscopy allows one to obtain spatially resolved information at the highest level of sensitivity. In the topic "Fluorescence Microscopy" we present the physics and the optical spectroscopy of molecules and cover the basics of microscopy, laser spectroscopy, and fluorescence microscopy. During the practical exercise, bacteria as well as polymer beads which are labelled with fluorescent chromophores will be studied with modern equipment. Also the related technique of Raman microscopy will be addressed, which provides spatially resolved information on the chemical composition of the sample. The literature on recent research activities in the field of fluorescence microscopy will be discussed in a seminar.

5 Diffusion in Polymers Werner Köhler, Experimental Physics IV, Polymer physics Diffusion, the uncorrelated motion of molecules, plays a key role in understanding dynamical processes in macromolecular systems. In the first part of this topic basic concepts of how polymers diffuse in the bulk and in solution are introduced. The difference between self and collective diffusion is discussed and it is shown that a temperature gradient can also because mass diffusion. Relevant experimental techniques for the measurement of diffusion coefficients are discussed in the second part. The last part takes place in the laboratory, where some experiments are performed together in the group, utilizing state-of-the-art equipment. The lectures will cover phenomenology of diffusion, including polymer models, linear laws, self diffusion, collective diffusion and thermal diffusion. As experimental techniques, light scattering and transient holography will be covered. Blockcopolymer Nanotechnology Georg Krausch, Physical Chemistry II The inherent self-organization of block copolymers leads to the spontaneous formation of regular structures with characteristic length scales in the nanometer regime. With the growing interest in the controlled formation of nanostructures, block copolymers have gained an increasing interest for technological applications. In this module, we will briefly introduce the basics of block copolymer chemistry and physics. We shall then discuss various recent examples where block copolymers have successfully been utilized to create useful nanostructures (e.g. nano-membranes, arrays of nano-wires, arrays of quantum dots, etc.). We will then turn to the laboratory and try to fabricate a block copolymer nanostructure based on existing materials. We shall explore suitable microscopy techniques for the imaging of organic nanostructures.

6 Microorganisms and Macromolecules Ortwin Meyer, Microbiology We will present two lectures (including an invited one), a seminar and one set of experimental work on the above mentioned topic. We will cover biochemical, biological and chemical aspects of the macromolecules which serve as a basis for structure and key functions of microorganisms. Most of them are of current applied and industrial interest. Examples of such macromolecules are the following: capsules and slime layers (e.g. polysaccharides), carbon storage polymers (e.g. poly-ß-hydroxybutyrate), compounds of functional relevance (e.g. proteins, nucleic acids), components of the cell wall (e.g. peptidoglycan, lipopolysaccharides). The course will include lectures on high lights of current interest in microbiology, macromolecules in the microbial world, microbes in action and experimental work to get in touch with biomacromolecules. Conclusions, perspectives and new approaches to biomacromolecules will be discussed in a round table discussion. Biomechanics and Parallel Measurement to Study Molecular Networks Prof. Albrecht Ott, Experimental Physics I, Biological physics The coupling of Biochemistry and Force/Motion-Generation has raised major interest during the last years. Starting with a review of intermolecular forces as they are described in Physics, we present recent advances in the field of biomolecular adhesion. We discuss single molecule bond failure as well as adhesion through multiple bonds. We show that cell-adhesion is deeply implicated in the biological information-exchange. Active force generation as achieved by molecular motors is another important aspect of biomolecules. We give details about molecular motors like actin-myosin known from the striated muscle. We review experimental progress and present physicist's ideas about functional aspects of directed biological transport. As an outlook to future biophysical work, we pinpoint recent advances in massif parallel measurements as they can be obtained by so called chip measurements.

7 We take the example of gene Chips and show interesting emerging ideas in the field. The lecture is followed by a tour in the laboratory, where some experiments can be visited hands on. No prior knowledge about biological systems is required to follow the lecture. Structure and Dynamics of Bio-Macromolecules in Solution Paul Rösch, Biopolymers Proteins and nucleic acids are the polymeric building blocks of live. Their three-dimensional structures are investigated in the field of structural biology. In our department we focus on hetero-nuclear, multi-dimensional nuclear magnetic resonance (NMR) spectroscopy as main tool to elucidate structural and dynamical properties of bio-macromolecules. This technique is supplemented by optical spectroscopy, such as circular dichroism and fluorescence spectroscopy. The teaching module consists of a lecture series introducing biopolymer structure, concepts underlying the physical techniques used for structure determination, and mathematical methods to translate the acquired data into three-dimensional structures of bio-macromolecules. Practical aspects of sample preparation for NMR-spectroscopy will be part of the lecture series. The type of results achievable in structural biology will be exemplified with allergens and HIV-related protein-nucleic acids complexes. Nanobiochemistry Mathias Sprinzl, Biochemistry

8 Supramolecular Macromolecules Hans-Werner Schmidt, Macromolecular Chemistry I We will present in a series of introductory lectures the concepts and underling principles of supramolecular macromolecules and self-assembling of molecules. Special emphasis will be given on hydrogen bonded supramolecular polymers and assemblies. Low molecular weight organogelators and nucleating agents for semi-crystalline polymers will be reviewed as two special selected topics. The project afternoon includes experiments on polymer nucleation and gelation of organic solvents and a discussion on selected literature articles. Color - Modern Aspects in Macromolecular Science Peter Strohriegl, Macromolecular Chemistry I Colors have attracted people for thousands of years. In the first part of the course, a short introduction in the physics of color formation and color mixing will be given. Afterwards, recent aspects of color formation will be discussed on two examples. The first one is the field of reflective colors from cholesteric mesophases with a distinct viewing angle dependence of the color. Such materials are used in effect paints for cars and other consumer goods. The second example are displays from organic light emitting diodes (OLEDdisplays). Here the physical principles of energy transfer from a host matrix to a guest molecule are used in a tricky way to manufacture full color displays. Energy transfer from an organic host to a dopant molecule will be shown experimentally in a project afternoon.