Project funded from European Commission FP7 [2011-2014]
Title: Multiscale computational approach to design of polymer matrix nanocomposites
Project leaders: Prof. Dr. Alexei R. Khokhlov
Project funded from German Federal Ministry of Education [2010-2013]
Title: Energy Related Nanomaterials
Project leaders: Prof. Dr. A. Khokhlov
Projects within SFB 569 [2008-2011]
Title: Self-organizing bioinspired oligothiophene-oligopeptide-hybrids - A joint experimental and theoretical approach
Project leaders: Prof. Dr. A. Khokhlov, Prof. Dr. P. Bäuerle (Organische Chemie II)
This project aims at (nano)structure formation in self-assembling bioinspired oligo-thiophene-oligopeptide "molecular chimeras", in bulk and on substrates. The study of these molecular systems begun very recently and has been initiated by the parties involved. Using a joint experimental and theoretical approach by organic synthesis and molecular modelling with an atomistic approach, we will focus on novel self-organizing and “bioinspired” hybrid structures consisting of semiconducting oligo- or polythiophene and biomimetic peptide blocks capable of forming ordered noncovalently bonded supramolecular structures via reversible hydrogen bonding of the peptide blocks. Variations of the semiconducting block on one hand and the peptide sequence on the other hand are planned in order to understand the self-assembling behaviour of this new class of hybrid compounds. A special attention is paid to the investigation of the self-assembling properties in solution, the bulk and in adsorption layers. The work is directed towards the development of new biomimetic ways of the formation of semiconducting fiber-like or helical supramolecular structures and conductive ultrathin films with mechanical properties mimicking natural silk.
Project funded from DFG [2006-2013]
Title: Effect of magnetic and electric fields, mechanical stress on the conformational state and release behavior of composite gels with embedded colloid particles
Project leaders: Prof. Dr. Alexei R. Khokhlov
Project funded from DFG [2006-2010]
Priority Program: “Schwerpunktprogramm” 2006 – 2010
Title: Intelligent Hydrogels
Project leaders: Prof. Dr. A. Khokhlov, Prof. Dr. K. Landfester, Prof. Dr. N. Hüsing
Projects within SFB 569 [2004-2011]
Title: Smart copolymers near patterned substrates: surfacemodulated morphologies
Project leaders: Prof. Dr. A. Khokhlov, Prof. Dr. I. Potemkin
In the present project we are going to develop a theory and perform computer simulations in order to investigate the stability of possible microstructures of the melts of copolymers, polymer blends, and polyelectrolyte complexes in thin, free-surface films and films confined between two solid surfaces, one of which carries a chemically active pattern. The basic idea is to study novel microstructures formed in the polymer matrix through the selective adsorption interaction and the interplay between intrinsic length scales of the surface pattern and of the polymer systems. We are going to explore polymer systems, which undergo reversible transformations and, thus, can be switched forward and backward between different types of assemblies or between different types of morphologies. In particular, it is planned to study polymer-assisted generation of three-dimensional patterns by replicating two-dimensional substrate motifs via selective adsorption of designed copolymers with tunable monomer sequence distribution, multiblock copolymers, copolymers of complicated chemical structure (such as double combs), oppositely charged polyelectrolytes, etc. Theoretical approaches that will be used include field-theoretic SCMF methods, adaptive/hybrid multiscale simulations (MC/pRISM, MD/pRISM, MC/SCF), quenched-annealed models of adsorption: replica Ornstein-Zernike approach, evolutionary approaches for sequence design and pattern design, and information-theoretic-based methods
Projects within SFB 569 [2004-2007]
Title: Adsorbed Comb-like Copolymers as a Tool for Multifunctional Molecular Devices
Project leaders: Prof. Dr. A. Khokhlov, Prof. Dr. O. Marti (Inst. für Experimentelle Physik), Prof. Dr. I. Potemkin
The project is directed towards theoretical and experimental studies of comb-like copolymers adsorbed on a flat surface. We are planning to investigate the properties of both single molecules and monofilms. The basic aim is to predict theoretically and realize experimentally optimum ways in controlled manipulation of macromolecular conformations. For this purpose response of two main factors, controlling the conformation of the adsorbed molecules, namely (i) the strength of the side chains/surface interactions and (ii) the symmetry of left-right distribution of the side chains relative to the backbone will be studied depending on the applied external stimuli (thermal (solvent quality), mechanical (AFM tip), light, etc.). We are planning to study comb-like macromolecules, including copolymers with two different types of side chains, side chains containing associating groups, photosensitive groups etc. Synthesis of these macromolecules will be performed both by grafting reactions and via different polymerization techniques. Special attention will be focused on the study of dynamics of the molecules.
Project funded from Wolfgang Paul Award [2002–2004]
Title: Sequence Design of Functional Copolymers
Project leader: Prof. Dr. A. Khokhlov
The Wolfgang Paul Award Project “Sequence Design of Functional Copolymers” is aimed to develop new types of functional polymer macromolecules via clever design of sequences of monomer units in a copolymer chain. This approach is biomimetic in its nature: for main biopolymers (DNA, RNA and proteins) the ability to perform highly complex and diverse functions is associated with unique primary sequences in copolymer chains of these biopolymers. These sequences emerged in the course of biological evolution.
In this project, on basis of our understanding on how the sequences in biopolymers define functional properties, we are formulating and implementing similar ideas for synthetic copolymers able to perform sophisticated functions. Also, one of the motivations of the project is the attempt to understand, at least partially, the principles of the evolution of sequences of biological macromolecules at the early stages of the evolution.
Volkswagen-Stiftung Project No I 77 775 [2001-2003]
Title: “Structure and Dynamics of Adsorbed Comblike Copolymers: Single Molecules and Monofilms”
Project leaders: Prof. Dr. Martin Möller (Deutsches Wollforschungsinstitut an der RWTH Aachen ), Prof. Dr. Igor Potemkin
The aim of the project is the synthesis of novel intelligent hydrogels composed of thermoresponsive cross-linked polymer network without or with entrapped emulsions of lipophilic substances by a combination of advanced techniques such as (mini)emulsion polymerization and polymerization in a frozen medium. The peculiarity of the composite gels will be the use of biocompatible oils and surfactants based on biopolymers further to the traditional synthetic surfactants. In addition to neutral gels slightly charged composite gels will be synthesized. Together with the synthetic aspects, the volume phase transitions of the composite gels will be studied. Investigations of the emulsions before and after the gel formation and after the release from the collapsed gel will be studied using optical and electronic microscopy, atomic force microscopy, dynamic light scattering and small-angle X-ray scattering. Absorption–release properties of the composite gels will be investigated for some typical drug compounds, model organic substances as well as surfactants and dyes and correlated to their structure and chemical composition using UV-spectrophotometry.
Projects within SFB 569 [2001-2003]
Title: Microheterogeneities in associating polyelectrolytes
Project leaders: Prof. Dr. Alexei R. Khokhlov, Prof. Dr. I. Potemkin
The aim of the present project is to perform theoretical studies of micro- and macrostructures, which are formed in various systems of associating polyelectrolytes. In particular, we are going to study dilute and semidilute solutions of associating polyelectrolytes, their freestanding films and thin fibers drawn from solution, and polymer-surfactant complexes adsorbed on a flat surface. Both equillibrium and rheological properties of such systems will be described.