JoinHEC – Vývoj nových metód spájania vysoko-entropických keramických materiálov
Development of new joining methods for high entropy ceramics
Program: Bilateral – other
Project leader: Ing. Tatarko Peter, PhD.
Annotation: The main aim of the proposed project is to develop new joining techniques for high entropy ceramics (HEC) in order to improve the operational limits of the joints for aerospace applications. The project proposes an innovative way of manufacturing of HEC joints with potentially improved high temperature properties, using a direct solid-state diffusion bonding (without an interlayer) or diffusion bonding with refractory metal interlayers. For the first time, refractory high entropy alloys (HEA) will be used as the joining interlayers between a pair of HEC, or as the interlayer for joining of HEC to ceramic matrix composites (CMCs). The project aims to generate new fundamental knowledge on the understanding of the effect of electric field and surface preparation on the direct diffusion bonding of HEC, as well as the interfacial physico-chemical phenomena occurring at the HEC/HEA and HEA/CMCs interfaces. The mechanical performance of the joints at room and high temperatures will be investigated to define the operational limits of the joints. The project will provide a comprehensive insight on the joining of high entropy ceramics for potential aerospace applications. This may significantly expand the application potential of the recently developed next generation ultra-high temperature ceramics, i.e. high entropy ceramics.
Duration: 1.7.2022 – 30.6.2025


BENTONITE – GAP – Bentonit: strategická surovina Slovenska – inovatívne hodnotenie zdrojov a ich kvality pre jej efektívne využívanie
Bentonite: Slovak strategic raw material – Innovative assessment of bentonite quality and origin for its efficient use
Program: SRDA
Project leader: RNDr. Madejová Jana, DrSc.
Annotation: Bentonite is an important industrial raw material. Due to the high amount of clay minerals from the smectite group, bentonite has unique properties, e.g. high swelling capacity, plasticity, high specific surface area, cation exchange capacity and low hydraulic conductivity. Due to these properties bentonites have broad range of possible applications. Consequently, worldwide bentonite production is constantly increasing. Slovak republic (SR) is one of the world\’s leading bentonite producers and bentonites belong to the strategic raw materials in SR. In the last 10-15 years, several new bentonite deposits have been opened in SR, most of which have never been studied in detail.Which is one of the causes that the potential of Slovak bentonites is not fully utilized. One of the objectives of the project is therefore the comprehensive characterization of bentonites from new deposits. The mineral and chemical composition of bentonites, their physico-chemical, mechanical, and rheological properties will be determined. The obtained results will help to better understand the geology and genesis of bentonite deposits which may lead to thediscovery of other economic accumulations of bentonites. The main contribution of the project lies in the rational, economical, and efficient use of domestic raw materials which will lead to the long-term sustainability of bentonite exploitation in SR. The way in which the proposed changes will be implemented is highly innovative. The main application outputs of the project such as: passports for the optimal utilization of different qualitative types of bentonites, including economic analysis, 3D model of bentonite quality and geological model of selected bentonite deposit, will contribute to achieve this ambitious goal. The multidisciplinary team of experts on domestic and worldbentonites in cooperation with major bentonite producer in SR, REGOS, s.r.o. is guarantee of successful solution ofthe proposed project.
Duration: 1.1.2021 – 30.6.2025
Potenciál vrstevnatých aluminosilikátov ako excelentných nosičov polykatiónov: dizajnovanie nových kompozitných nanomateriálov
Potential of layered aluminosilicates as excellent guests to accommodate polymeric cations: design of new composite materials
Program: VEGA
Project leader: Ing. Pálková Helena, PhD.
Annotation: The project is aimed at the preparation of composite materials based on layered aluminosilicates as suitablecarriers for different types of organic polycations, possessing properties interesting for various applications. Thevariability in the chemical composition of the selected layered materials in connection with the diversity of themolecular structures and properties of polymeric cations and copolymers opens up wide opportunities towardsthe preparation of well-defined systems. Careful selection of the inorganic carries and polycations is an essentialstep to achieve their mutual compatibility resulting not only in preserving but primarily in improving the keyproperties of the prepared composites. Therefore, the synthesis conditions (e.g. pH) and the addition of anothercomponent to the systems (fluorescent dyes, metal nanoparticles) will be evaluated. The cytotoxicity test topredict biocompatibility of the materials, photoactivity, catalytic and adsorption efficiency will be assessed as well.
Duration: 1.1.2021 – 31.12.2024
BioPolSil – Bionanokompozitné materiály na báze vrstevnatých silikátov
Bionanocomposites based on organic polycations and layered silicates
Program: SRDA
Project leader: RNDr. Madejová Jana, DrSc.
Annotation: The basic research project deals with the preparation and complex characterisation of the structurally unique typesof hybrid materials consisting of clay minerals from smectite group and new synthesized poly(ethylene imine)based polycations. Polymerization of oxazolines opens a wide range of possibilities for the preparation of welldefinedpolycations with precisely designed molecular architectures and properties in order to prepare suitableintercalating agents for clay minerals modifications. The aim is to provide nanocomposites with interestingbiocompatible or biodegradable properties. To achieve this aim a detailed investigation of the effect of variousfactors on the molecular characteristics of poly(ethylene imine) based polycations and consequently on theirbehavior upon smectites interlayers intercalation has to be performed using wide range of different experimentaltechnique (e.g., XRD, XPS, MAS NMR, and IR spectroscopies) but also by means of DFT method in the solidstate.Biocompatibility of prepared polycations and their smectite intercalates will be assed based on cell viability assayand cell morphology after direct contact with selected substances. Prepared polycationic-smectites will be furtherstudied due to their possible applications as new types of fillers for selected biodegradable polymers, drug-deliverysystems and as new composite materials with optical properties. Interdisciplinary project, as designed, providesunique platform for understanding the properties of the newly synthesized polycation-smectite composites. This approach can significantly contribute to the current level of knowledge in the fields of nanomaterials and has the potential for acquiring fundamentally new results.
Duration: 1.7.2020 – 30.6.2024