Research Projects

Polyurethanes (PU) feature an extremely broad range of end-use properties (density, stiffness, hardness, etc.). They are mainly used in the form of foams (flexible, semi-rigid, rigid) in construction, transportation, furniture (bedding) and footwear. In some special applications, PUs are used as soft solid elastomers or hard solid plastics. Main materials for PUs preparation are: oligomeric polyol, isocyanate, chain extender/crosslinker. Though design properties of PUs are different, the number of components for their preparation is quite narrow. The most common (“classical”) PUs are based on polyether (PE) or polyester (PES) diols or triols and aromatic di- or poly- isocyanates. PUs prepared from polybutadiene- (PB) or polycarbonate- (PC) diols belong to the group of specialty products, due to enhanced enduse properties of PB-PUs and PC-PUs compared with “classical” PUs.
The project will be aimed on the preparation and characterization novel PUs made from polycarbonate (PC)-based macrodiols, aliphatic or aromatic diisocyanates and aliphatic chain extender/crosslinker. In some cases, inorganic nanofiller will be added. One-step and/or two-step (prepolymerization) techniques combined with solvent or solvent-free systems will be used. Multidisciplinary characterization (advanced techniques of analyses included) of PCPUs will be done in order to study relationship: material choice – preparation technique – enduse properties that will be compared with “classical” PUs, eventually PBD-based PUs.

The aim is to produce nanosized magnetic iron oxide particles by different methods and to compare their efficiency in biological applications after their coating with a polymer and functionalization to introduce reactive groups for subsequent immobilization of biologically active compounds.

Polymer blends are very important materials with broad scale of possible applications. Their properties, especially mechanical, are dependent on their phase structure. The phase structure can be controlled by the blend composition, addition of a compatibilizer and conditions of the blend preparation. It was found that polymer blends based on polycycloolefins (COC) are very promising materials for skeletal replacements (parts of bones, joints, etc.), which need materials with high modulus and impact strength simultaneously. The aim of the project is optimized structure and properties of COC with convenient elastomers according to the requirements on considered skeletal replacements. Present state of knowledge of the phase structure evolution in immiscible polymer blends will be utilized for this purpose

Polymer nanocomposites based on epoxy, polyurethane and polycaprolactone systems as well as polymer hydrogels modified with various types of inorganic nanofillers, such as silica, layered silicates etc. will be investigated. Both preformed nanoparticles and nanostructured fillers formed in situ will be applied for synthesis of the nanocomposites. The project will consists in preparation of nanostructured polymers, characterization of the hierarchical structure (from molecular to macroscale) and determination of the properties (thermomechanical, optical, electrical). The research will be focused on control of the morphology and structure of the organic-inorganic polymers in order to optimize their properties. Determination of the relationships between structure and properties of the nanocomposites will be the goal of the project.

Pluronics is a commercial name for a group of tri-block co-polymers of poly (ethylene oxide) – poly (propylene oxide) – poly (ethylene oxide). Pluronics micellise upon increasing temperature and/or concentration, micellisation may be followed by gelation. Physical hydrogels are of interest in, e. g., medicine as drug delivery systems. Mechanisms of the association (micellisation and gelation) processes are not yet fully understood. Modified Pluronics have been synthesised in order to follow the impact of molecular structure on association. The subject of the project is a study of the processes of micellisation and gelation of modified Pluronics by the means of vibrational (Raman and infrared) spectroscopy.

The project is focused on improving economy of protection of polymers against deterioration of their properties due to weathering. This goal can be reached by utilizing cooperation between components of stabilization mixture of additives and optimization of composition of the mixture. Studies of spatial resolution (profiling) of photodegradation process inside polymers can provide important information required. Hindered amine stabilizers (HAS) are the most common class of additives applied in photoprotection of carbon-chain polymers, polyolefins in particular. Formation of HAS-derived nitroxides is the assumed primary step of the stabilizing activity of a secondary HAS and is considered as a proof of their photoantioxidant activity. Concentration profiles of nitroxides inside commodity polymers (polypropylene, polystyrene, polyethylene, poly(ethylene-co-norbornene) subjected to accelerated weathering will be measured by electron spin resonance imaging (ESRI) in dependence on the duration of irradiation in weatheometer under proper conditions. In the same dependence changes in polymer transparency, changes in concentrations of carbonyl and hydroxy groups on the surface and inside the samples, and changes of integral mechanical properties of polymers will be studied.

π -Conjugated polymers for organic solar cells will be synthesized and characterized. To do that it is necessary to prepare tailored monomers convenient for polymer synthesis first. The synthesis of new aromatic (carbazole, fluorene, anthracene or benzene derivatives) diboronic acid esters will be performed by means of organic chemistry. These materials will be used together with aromatic dibromo comonomers for Suzuki polycondensation reaction to prepare the polymers. Photovoltaic behavior of the prepared materials will be studied by optical methods.

Main idea: Major problem of synthetic polymer nanocomposites is to achieve a good dispersion of nanofiller in polymer matrix. That is why we developed the sandwich method, which is optimized for small samples (10mm x 10mm x 0.5mm) containing homogeneously dispersed nanoparticles. Such specimens are currently used for detailed investigation of nucleation effects and could be also employed in photovoltaic applications.

Task: Preparation of sandwich nanocomposites of polypropylene (PP) and various nucleating agents, such as gold nanoparticles (Au-NP) and commercial alpha- and beta-nucleants. The Au-NP will be prepared by both chemical way (synthesis in solution) and physical way (vacuum sputter coater). Characterization of nucleation effects by electron microscopy, differential scanning calorimetry and X-ray diffraction.

Originality: Sandwich method is our own, new technique for reproducible preparation of polymer nanocomposites, which will be published soon. By means of this method, we will be able to reliably answer the long-standing question of polymer physics: is the nucleation activity of Au-NP (and also other metallic nanoparticles) influenced by their size, shape and/or chemical purity?

Cell adhesion to extracellular matrix (ECM) components is necessary for the development, organization, and maintenance of tissues. Biomaterials that could substitute ECM ligands and promote cell adhesion are important for numerous biotechnological and biomedical applications, such as artificial organs, biomaterials for tissue regeneration and tissue engineering, and synthetic supports for in vitro cell cultures. In vivo, cell adhesion to ECM proteins is primarily mediated by integrins, transmembrane receptors composed of α and β subunits. Integrins bind to specific amino acid sequences of the ECM proteins. Well-known example of such adhesion peptides comprises the arginine–glycine–aspartic acid motif present in many ECM proteins, including fibronectin and vitronectin. The aim of the work is to prepare synthetic polypeptides (artificial proteins) containing non-essential amino acids suitable for selective „click-like“ chemical modification. The second part of the work is biomimetic modification of the prepared synthetic polypeptides.

Polymers and polymer composites find an increasing use as advanced active materials in optoelectronics. The proposed work should be focused on a preparation of suitable polymer nanostructures and on the study of general relationships between the molecular and supramolecular structure and efficiency of photogeneration and transport of charges. The final aim is to optimize photoelectrical parameters for a potential application of polymers in photovoltaic solar cells. Polymers with suitable chemical structures have to be found, which yield a proper position of energy levels and extended electron delocalization. Theoretical approach will be combined with experimental studies, mostly by steady-state and time- resolved measurements photoelectrical phenomena. According to the background of a candidate either experimental or theoretical character of the work can be accented. We expect a tight collaboration activity with various laboratories in Europe.

The project will be devoted to the investigation of interactions polymer-solvent (hydration) and polymer-polymer in aqueous solutions (or gels) of stimuli-responsive polymers which show a phase transition of the coil-globule type. This transition can be induced by temperature, solvent composition etc. Multicomponent polymer systems with various architecture will be studied, e.g,, mixtures of thermoresponsive polymers, block or graft copolymers containing thermoresponsive blocks or grafts, or responsive two-component interpenetrating networks. Information how the architecture of the polymer system affects the phase-separated globular-like structures on various level should be obtained. This includes information on the fraction of monomer units in these structures, on changes in hydrogen bonding of specific functional groups and arrangement of water molecules, and in changes in dynamics of polymer segments and water due to the phase transition. The knowledge how the structure and interactions (hydration) are changed in a multicomponent system in comparison with the respective responsive homopolymer(s) should provide more information which is important to design materials with specific properties. NMR spectroscopy (including NMR relaxation measurements) will be the main method in these investigations. It can be combined with vibrational spectroscopy and other physical methods when this will be desirable.

Study of optical, electrochemical, electrical and photoelectrical properties of new polymers and polymer blends for photovoltaic (PV) applications. Modern laboratory equipment enables study of thin film properties, preparation and characterization of PV cells in an inert atmosphere. Character of the work is mainly experimental, but also theoretical knowledge can be utilized in particular for the interpretation of experimental data.

Modeling of optical, electrical and transport properties of thin polymer layers for photovoltaic devices, modeling of photovoltaic characteristics of polymer photovoltaic devices of various configuration.

Study of the complex effect of nanoclays on the structure and behaviour of polymer phase modified epoxy resin. The goal is to achieve favourable combination of clay reinforcement and influencing the dynamic phase behaviour including formation of advantageous morphology of dispersed phase. Analysis of the effect of complex inclusions structure and parameters on system behaviour, FEM modeling.

Organic-inorganic (O-I) polymers based mainly on siloxanes and stannoxanes will be synthesized, in form of homogeneous materials, as well as nanocomposites with organic polymers. The project is aimed at obtaining novel polymers with attractive mechanical and thermal properties and with good oxidation resistance. Apart from synthesis work, rheological properties during polymer formation (chemorheology, gelation) and the mechanical propertuies of the final products (DMTA) will be characterized directly in our department by the course participant, while further extensive characterization of the polymers will be done by cooperating with other departments our Institute: especially morphology (WAXS, SAXS, TEM), chemical microstructure (NMR) and thermogravimetry (TGA).

Stimuli-responsive polymers showing a nonlinear response to an external signal have gained much interest as ‘‘smart’’ and advanced materials in the last few years. Among these, thermoresponsive polymers exhibiting lower critical solution temperature (LCST) behavior in aqueous solution represent an important class, especially for biomedical applications, and in particular to research related to tumors that exhibit a higher temperature than normal body temperature. The inverse temperature-dependent solubility leads, e.g., to association of polymers above LCST and this effect can be exploited for various biological applications.

An example of an important family of thermoresponsive polymers that is under-researched and under-utilized is that of polyoxazolines. These polymers exhibit a number of attractive features compared to other thermosensitive polymers: 1. they are structurally closer to polypeptides than the often used N-isopropylacrylamide polymers, since the amidic nitrogen is located in the main chain and not in the side group; 2. they can be synthesized in a controlled way with a narrow molecular weight; 3. they are easily copolymerized with other oxazoline monomers to create random, block, gradient and branched copolymers with adjustable LCST.

Research in this project aims at the synthesis (or preparation), study of physicochemical properties and fine-tuning of structural properties of new thermoresponsive polymers (e.g., based on polyoxazoline) and of their micelles and nanoparticles with respect to their potential use in biological applications, for example in the drug delivery field. Work can also be oriented to stimuli-sensitive polymers and copolymers and nanoparticles of applicant’s own interest.

Affinity biosensors use biological receptors attached to a physical transducer for binding specific analytes. For in real-time detection in biological media it is convenient to immobilize the receptors on the transducer coated with an antifouling polymer layer which prevent nonspecific deposition of biological compounds.
The work will include the preparation of ultra-thin hydrogel layers on surface plasmon resonance (SPR) sensors. Bioreceptors, such as, antibodies and antigens, will be covalently attached to the hydrogel. The layers will be characterized by IR reflection spectroscopy and AFM, and the detection of the respective analytes in blood serum will be tested by SPR. The results will be utilized for the development of protein chips applicable in medical diagnostics.

Deposition of proteins from complex biological media, such as, blood, plasma, serum, cell, culture media, protein mixtures, cell suspensions, or tissue extracts makes serious troubles in many applications of artificial materials in biotechnologies and medicine.
The aim of the work will be the development of anti-fouling polymer layers which prevent protein adsorption from the biological media and contain reactive chemical groups for covalent attachment of biologically active molecules. The activities will include mainly coating surfaces of artificial materials with homo- and co-polymer brushes using surface initiated radical polymerization (ATRP, ARGET) of various hydrophilic acrylates, methacrylates, acrylamides, and methacrylamides. The layers will be characterized by IR reflection spectroscopy and AFM, the interaction with biological media will be studied by SPR. The results will be applied to coatings biosensors or micro- and nano-particles for diagnostics and separation.

The main project activity will be preparation, characterizion and possibly modelling of strong hydrogels with good shape memory. These hydrogels will be designed for further development of prosthetic material for replacement of soft tissue in orthopaedy and spine surgery. The hydrogels will have high durability and shape memory and will possess self-reinforcing properties when mechanically loaded.To achive reversibility of the systems, mainly block copolymers built of hydrophilic blocks (A) with hydrophobically aggregating and possibly crystallizing blocks (B), mainly triblock BAB and multiblock -(AB)x- will be investigated.

Characterization will include kinetics of gel formation, time dependences of free swelling of gels and gels in confined geometries, hydraulic permeability, effect of external stress on swelling, rheology and shape memory. Modeling will concern swelling and elasticity with a scientific software recently developed within our group may be used. The participant may perform case studies using input data obtained from her/his experimental work.