Solid electrolytes for the Lithium-Ion Polymer Battery can be produced by mixing a lithium salt, typically LiPF6 or LiBF4, into poly(ethylene oxide) (PEO), -(CH2CH2O)n-. However, such electrolytes only exhibit adequate ionic conductivity (>10-4 S/cm) at temperatures above 70°C, where the polymer becomes amorphous. The conventional wisdom has been that the high degree of local order (“crystallinity”) is the reason for the poor ionic conductivity at ambient temperatures. Much attention has therefore been devoted to the task of increasing the amorphous content of the PEO electrolyte at ambient temperatures.
Molecular Dynamics (MD) simulations give us a chance to have close insights into Nafion's dynamics and local structure on molecular level. We can study the details of proton-conductivity and find out the mechanisms what can possibly improve this process. We are interested in following research problems:
- design of the realistic and reliable Molecular Dynamics simulation model for Nafion as an electrolyte in the fuel cell,
- simulations of proton hopping mechanism between Nafion chain and surrounding water,
- the effects of Nafion side chains on the proton dynamics.
This research focuses on building EAP devices as well as methods for their control. Particularly, we are focusing at the following research problems:
- Electromechanical modelling of IPMC materials
- Design of novel IPMC actuators.
- Development of position sensors for IPMC actuators.
- Development of control methods of IPMC actuators to achieve less energy consumption at large output force and torque.
- Development of feedback control methods for IPMC actuators.
- Design of autonomous IPMC actuators and devices.
Learning and adaptation are inherent capabilities in dynamic and partially unknown environments. Properties of such kind of environments are not known in advance and therefore it is not possible to model the correctly. It is also likely that information about the environment contains noise and ambiguity.
At present, underwater vehicles almost exclusively use propeller and jet engines for propulsion and motion control. Underwater vehicles using this technology are reliable, powerful and with a well established theoretical background. However, aquatic animals almost exclusively use other methods of locomotion. At the same time their behaviour is characterized by very efficient propulsion, great maneuverability and silent motion. This project developed a biomimetic underwater vehicle for shallow water application and the methods of it's control.
The Study of Cell Penetrating Peptides (CPPs) by Means of Imaging Techniques
CPPs are peptides that are capable of penetrating cell membranes otherwise impermeable and carry different covalently or non-covalently bounded cargo molecules (i.e. peptides, proteins, plasmids, ON-analogues, siRNA, decoy DNA) into a cell. These peptides are usually less than 30 amino acids in length, they are positively charged and/or amphipathic. Albeit CPPs have been proven to be very useful and promising tools in medicine their uptake mechanism is not clear. The goal of the research is to gather data matrix on the cellular uptake of CPPs and to characterize the cellular intake of CPPs. We experiments with different CPPs which differ in their length, composition, net charge, lipophility, structure, and hydrophobic properties. The selection includes both endocytosis independent and -dependent CPPs. Effect of endocytosis inhibitors, temperature, incubation times and CPP concentration on CPP uptake and on CPP intracellular distribution will be analyzed. CPP cell intake experiments will be carried out also with different types of cargoes (short PNA, peptides, avidin) in order to estimate effect of cargo-CPP bulk properties on internalization process. In order to make CPPs observable a fluorophore will be attached to CPPs. The cellular intake of CPPs will be registered by means of confocal microscopy and spectrophotometry. Based on the data collected a model for CPP prediction will be proposed and likely cellular intake mechanisms will be specified.
Material study of conducting polymers
Electronically conducting polymers, polypyrrole (PPy) in particular, have been under heavy investigation during the last decades. Their useful optical, conductive, ion-exchange properties have already found use at the industrial level in various capacitors, displays, sensors, analyzers, etc. In addition to the practical use of these “classical” properties, several promising applications of the conducting polymers have been proposed in recent years, employing the bio-compatibility or electromechanical features of these polymers. Unfortunately, the lack of fundamental atomistic understanding of the development of the properties of the conducting polymers is hindering the wider use of the novel applications proposed. Our main focus has been the establishment of the relationships between the synthesis conditions, the structure and the properties of the polymers. Another field of interest is the stability (both chemical and physical) of these materials (especially if used in air, aqueous solutions or bio-liquids). Electrochemistry, spectroscopy, electron- and probe microscopy as well as theoretical modeling have been employed in order to gain a better understanding of these issues.